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ADC12DJ2700
SLVSEH9A – JANUARY 2018 – REVISED APRIL 2020
ADC12DJ2700 5.4-GSPS Single-Channel or 2.7-GSPS Dual-Channel,
12-bit, RF-Sampling Analog-to-Digital Converter (ADC)
1 Features
2 Applications
•
•
•
•
•
•
•
•
•
•
1
•
•
•
•
•
•
•
•
ADC core:
– 12-bit resolution
– Up to 5.4 GSPS in single-channel mode
– Up to 2.7 GSPS in dual-channel mode
Performance specifications:
– Noise floor (no signal, VFS = 1.0 VPP-DIFF):
– Dual-channel mode: –151.6 dBFS/Hz
– Single-channel mode: –153.8 dBFS/Hz
– HD2, HD3: –65 dBc up to 3 GHz
Buffered analog inputs with VCMI of 0 V:
– Analog input bandwidth (–3 dB): 8.0 GHz
– Usable input frequency range: >10 GHz
– Full-scale input voltage (VFS, default): 0.8 VPP
– Analog input common-mode (VICM): 0 V
Noiseless aperture delay (TAD) adjustment:
– Precise sampling control: 19-fs step
– Simplifies synchronization and interleaving
– Temperature and voltage invariant delays
Easy-to-use synchronization features:
– Automatic SYSREF timing calibration
– Timestamp for sample marking
JESD204B serial data interface:
– Supports subclass 0 and 1
– Maximum lane rate: 12.8 Gbps
– Up to 16 lanes allows reduced lane rate
Digital down-converters in dual-channel mode:
– Real output: DDC bypass or 2x decimation
– Complex output: 4x, 8x, or 16x decimation
– Four independent 32-Bit NCOs per DDC
Power consumption: 2.7 W
Power supplies: 1.1 V, 1.9 V
ADC12DJ2700 Measured Input Bandwidth
Normalized Gain Response (dB)
3
0
Communications testers (802.11ad, 5G)
Satellite communications (SATCOM)
Phased array radar, SIGINT, and ELINT
Synthetic aperture radar (SAR)
Time-of-flight and LIDAR distance measurement
Oscilloscopes and wideband digitizers
Microwave backhaul
RF sampling software-defined radio (SDR)
Spectrometry
3 Description
The ADC12DJ2700 device is an RF-sampling, gigasample, analog-to-digital converter (ADC) that can
directly sample input frequencies from DC to above
10 GHz. In dual-channel mode, the ADC12DJ2700
can sample up to 2700 MSPS and up to 5400 MSPS
in single-channel mode. Programmable tradeoffs in
channel count (dual-channel mode) and Nyquist
bandwidth (single-channel mode) allow development
of flexible hardware that meets the needs of both high
channel count or wide instantaneous signal
bandwidth applications. Full-power input bandwidth
(–3 dB) of 8.0 GHz, with usable frequencies
exceeding the –3-dB point in both dual- and singlechannel modes, allows direct RF sampling of L-band,
S-band, C-band, and X-band for frequency agile
systems.
The ADC12DJ2700 uses a high-speed JESD204B
output interface with up to 16 serialized lanes and
subclass-1 compliance for deterministic latency and
multi-device synchronization. The serial output lanes
support up to 12.8 Gbps and can be configured to
trade-off bit rate and number of lanes. Innovative
synchronization features, including noiseless aperture
delay (TAD) adjustment and SYSREF windowing,
simplify system design for phased array radar and
MIMO communications. Optional digital down
converters (DDCs) in dual-channel mode allow for
reduction in interface rate (real and complex
decimation modes) and digital mixing of the signal
(complex decimation modes only).
Device Information(1)
-3
PART NUMBER
-6
ADC12DJ2700
-9
BODY SIZE (NOM)
(1) For all available packages, see the package option addendum
at the end of the data sheet.
Single Channel Mode
Dual Channel Mode
-12
PACKAGE
FCBGA (144) 10.00 mm × 10.00 mm
-15
0
2
4
6
8
Input Frequency (GHz)
10
12
D_BW
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
ADC12DJ2700
SLVSEH9A – JANUARY 2018 – REVISED APRIL 2020
www.ti.com
Table of Contents
1
2
3
4
5
6
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
4
9
6.1
6.2
6.3
6.4
6.5
6.6
6.7
Absolute Maximum Ratings ...................................... 9
ESD Ratings.............................................................. 9
Recommended Operating Conditions..................... 10
Thermal Information ................................................ 10
Electrical Characteristics: DC Specifications .......... 11
Electrical Characteristics: Power Consumption ...... 13
Electrical Characteristics: AC Specifications (DualChannel Mode) ........................................................ 14
6.8 Electrical Characteristics: AC Specifications (SingleChannel Mode) ........................................................ 17
6.9 Timing Requirements .............................................. 20
6.10 Switching Characteristics ...................................... 21
6.11 Typical Characteristics .......................................... 25
7
Detailed Description ............................................ 35
7.1 Overview ................................................................. 35
7.2 Functional Block Diagram ....................................... 36
7.3 Feature Description................................................. 36
7.4 Device Functional Modes........................................ 60
7.5 Programming........................................................... 79
7.6 Register Maps ......................................................... 80
8
Application and Implementation ...................... 130
8.1 Application Information.......................................... 130
8.2 Typical Applications ............................................. 130
8.3 Initialization Set Up .............................................. 137
9
Power Supply Recommendations.................... 137
9.1 Power Sequencing ................................................ 139
10 Layout................................................................. 139
10.1 Layout Guidelines ............................................... 139
10.2 Layout Example .................................................. 140
11 Device and Documentation Support ............... 143
11.1 Device Support ..................................................
11.2 Documentation Support ......................................
11.3 Receiving Notification of Documentation
Updates..................................................................
11.4 Support Resources .............................................
11.5 Trademarks .........................................................
11.6 Electrostatic Discharge Caution ..........................
11.7 Glossary ..............................................................
143
143
143
144
144
144
144
12 Mechanical, Packaging, and Orderable
Information ......................................................... 144
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Original (January 2018) to Revision A
Page
•
Changed Pin Functions table listed in alphanumeric order by pin name. .............................................................................. 5
•
Deleted reference to footnote below the Pin Functions table and moved the information to the Power-Down Mode
section. ................................................................................................................................................................................... 7
•
Added Operating free-air temperature parameter to Absolute Maximum Ratings table ........................................................ 9
•
Added Storage temperature parameter to Recommended Operating Conditions table ...................................................... 10
•
Changed FFT plots in Typical Characteristics section to show improved look ................................................................... 25
•
Changed product description in Overview section .............................................................................................................. 35
•
Changed Device Comparison section to include all devices in the family. .......................................................................... 36
•
Changed location of Analog Reference Voltage section. .................................................................................................... 38
•
Changed location of Temperature Monitoring Diode section. ............................................................................................. 40
•
Added requirement for at least 3 rising edges of SYSREF before SYSREF_POS output is valid. ..................................... 43
•
Added clarification of NCO synchronization using DC-coupled SYSREF. ........................................................................... 49
•
Added clarification of NCO synchronization using AC-coupled SYSREF. ........................................................................... 50
•
Changed note in Power-Down Modes section to caution note explaining reliable serializer operation instead of the
information being presented under the Pin Functions table. ................................................................................................ 69
•
Changed the Low-Power Background Calibration (LPBG) Mode section to provide additional detail of how to
operate the device in low-power background calibration mode. .......................................................................................... 75
•
Added clarity about offset calibration when both CAL_OS and CAL_BG are enabled. ...................................................... 76
•
Changed Trimming section to limit trimming to foreground (FG) calibration mode only to better reflect customer use
cases and simplify the explanation....................................................................................................................................... 77
•
Changed additional clarity to Offset Filtering section to explain the frequency domain impact of the feature..................... 78
•
Added ADC12DJ2700 Access Type Codes table ................................................................................................................ 85
2
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Revision History (continued)
•
Added Reconfigurable Dual-Channel 2.5-GSPS or Single-Channel 5.0-Gsps Oscilloscope section ................................ 133
•
Changed Top Layer Routing: Analog Inputs, CLK and SYSREF, DA0-3, DB0-3 to Bottom Layer Routing: Additional
CLK Routing, DA4-7, DB4-7 figures .................................................................................................................................. 140
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SLVSEH9A – JANUARY 2018 – REVISED APRIL 2020
www.ti.com
5 Pin Configuration and Functions
AAV Package
144-Ball Flip Chip BGA
Top View
1
2
3
4
5
6
7
8
9
10
11
12
A
AGND
AGND
AGND
INA+
INA±
AGND
AGND
DA3+
DA3±
DA2+
DA2±
DGND
B
TMSTP+
AGND
AGND
AGND
AGND
AGND
AGND
DA7+
DA7±
DA6+
DA6±
DGND
C
TMSTP±
SYNCSE
BG
VA19
VA11
AGND
NCOA0
ORA0
VD11
VD11
DA5+
DA1+
D
AGND
VA11
VA11
VA19
VA11
AGND
NCOA1
ORA1
DGND
DGND
DA5±
DA1±
E
AGND
VA19
VA19
VA19
VA11
AGND
CALTRIG
SCS
VD11
VD11
DA4+
DA0+
F
CLK+
AGND
AGND
VA19
VA11
AGND
CALSTAT
SCLK
DGND
DGND
DA4±
DA0±
G
CLK±
AGND
AGND
VA19
VA11
AGND
VD11
SDI
DGND
DGND
DB4±
DB0±
H
AGND
VA19
VA19
VA19
VA11
AGND
VD11
SDO
VD11
VD11
DB4+
DB0+
J
AGND
VA11
VA11
VA19
VA11
AGND
NCOB1
ORB1
DGND
DGND
DB5±
DB1±
K
SYSREF+
TDIODE+
TDIODE±
VA19
VA11
PD
NCOB0
ORB0
VD11
VD11
DB5+
DB1+
L
SYSREF±
AGND
AGND
AGND
AGND
AGND
AGND
DB7+
DB7±
DB6+
DB6±
DGND
M
AGND
AGND
AGND
INB+
INB±
AGND
AGND
DB3+
DB3±
DB2+
DB2±
DGND
Not to scale
4
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Pin Functions
PIN
I/O
DESCRIPTION
NAME
NO.
AGND
A1, A2, A3,
A6, A7, B2,
B3, B4, B5,
B6, B7, C6,
D1, D6, E1,
E6, F2, F3,
F6, G2, G3,
G6, H1, H6,
J1, J6, L2, L3,
L4, L5, L6, L7,
M1, M2, M3,
M6, M7
—
Analog supply ground. Tie AGND and DGND to a common ground plane (GND) on the circuit
board.
BG
C3
O
Band-gap voltage output. This pin is capable of sourcing only small currents and driving limited
capacitive loads, as specified in the Recommended Operating Conditions table. This pin can be
left disconnected if not used.
CALSTAT
F7
O
Foreground calibration status output or device alarm output. Functionality is programmed through
CAL_STATUS_SEL. This pin can be left disconnected if not used.
CALTRIG
E7
I
Foreground calibration trigger input. This pin is only used if hardware calibration triggering is
selected in CAL_TRIG_EN, otherwise software triggering is performed using CAL_SOFT_TRIG.
Tie this pin to GND if not used.
CLK+
F1
I
Device (sampling) clock positive input. The clock signal is strongly recommended to be ACcoupled to this input for best performance. In single-channel mode, the analog input signal is
sampled on both the rising and falling edges. In dual-channel mode, the analog signal is sampled
on the rising edge. This differential input has an internal untrimmed 100-Ω differential termination
and is self-biased to the optimal input common-mode voltage as long as DEVCLK_LVPECL_EN
is set to 0.
CLK–
G1
I
Device (sampling) clock negative input. TI strongly recommends using AC-coupling for best
performance.
DA0+
E12
O
High-speed serialized data output for channel A, lane 0, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DA0–
F12
O
High-speed serialized data output for channel A, lane 0, negative connection. This pin can be left
disconnected if not used.
DA1+
C12
O
High-speed serialized data output for channel A, lane 1, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DA1–
D12
O
High-speed serialized data output for channel A, lane 1, negative connection. This pin can be left
disconnected if not used.
DA2+
A10
O
High-speed serialized-data output for channel A, lane 2, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DA2–
A11
O
High-speed serialized-data output for channel A, lane 2, negative connection. This pin can be left
disconnected if not used.
DA3+
A8
O
High-speed serialized-data output for channel A, lane 3, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DA3–
A9
O
High-speed serialized-data output for channel A, lane 3, negative connection. This pin can be left
disconnected if not used.
DA4+
E11
O
High-speed serialized data output for channel A, lane 4, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DA4–
F11
O
High-speed serialized data output for channel A, lane 4, negative connection. This pin can be left
disconnected if not used.
DA5+
C11
O
High-speed serialized data output for channel A, lane 5, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DA5–
D11
O
High-speed serialized data output for channel A, lane 5, negative connection. This pin can be left
disconnected if not used.
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Pin Functions (continued)
PIN
I/O
DESCRIPTION
NAME
NO.
DA6+
B10
O
High-speed serialized data output for channel A, lane 6, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DA6–
B11
O
High-speed serialized data output for channel A, lane 6, negative connection. This pin can be left
disconnected if not used.
DA7+
B8
O
High-speed serialized data output for channel A, lane 7, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DA7–
B9
O
High-speed serialized data output for channel A, lane 7, negative connection. This pin can be left
disconnected if not used.
DB0+
H12
O
High-speed serialized data output for channel B, lane 0, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DB0–
G12
O
High-speed serialized data output for channel B, lane 0, negative connection. This pin can be left
disconnected if not used.
DB1+
K12
O
High-speed serialized data output for channel B, lane 1, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DB1–
J12
O
High-speed serialized data output for channel B, lane 1, negative connection. This pin can be left
disconnected if not used.
DB2+
M10
O
High-speed serialized data output for channel B, lane 2, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DB2–
M11
O
High-speed serialized data output for channel B, lane 2, negative connection. This pin can be left
disconnected if not used.
DB3+
M8
O
High-speed serialized data output for channel B, lane 3, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DB3–
M9
O
High-speed serialized data output for channel B, lane 3, negative connection. This pin can be left
disconnected if not used.
DB4+
H11
O
High-speed serialized data output for channel B, lane 4, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DB4–
G11
O
High-speed serialized data output for channel B, lane 4, negative connection. This pin can be left
disconnected if not used.
DB5+
K11
O
High-speed serialized data output for channel B, lane 5, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DB5–
J11
O
High-speed serialized data output for channel B, lane 5, negative connection. This pin can be left
disconnected if not used.
DB6+
L10
O
High-speed serialized data output for channel B, lane 6, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DB6–
L11
O
High-speed serialized data output for channel B, lane 6, negative connection. This pin can be left
disconnected if not used.
DB7+
L8
O
High-speed serialized data output for channel B, lane 7, positive connection. This differential
output must be AC-coupled and must always be terminated with a 100-Ω differential termination
at the receiver. This pin can be left disconnected if not used.
DB7–
L9
O
High-speed serialized data output for channel B, lane 7, negative connection. This pin can be left
disconnected if not used.
DGND
A12, B12, D9,
D10, F9, F10,
G9, G10, J9,
J10, L12, M12
—
Digital supply ground. Tie AGND and DGND to a common ground plane (GND) on the circuit
board.
6
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Pin Functions (continued)
PIN
NAME
NO.
I/O
DESCRIPTION
INA+
A4
I
Channel A analog input positive connection. INA± is recommended for use in single channel
mode for optimal performance. The differential full-scale input voltage is determined by the
FS_RANGE_A register (see the Full-Scale Voltage (VFS) Adjustment section). This input is
terminated to ground through a 50-Ω termination resistor. The input common-mode voltage is
typically be set to 0 V (GND) and must follow the recommendations in the Recommended
Operating Conditions table. This pin can be left disconnected if not used.
INA–
A5
I
Channel A analog input negative connection. INA± is recommended for use in single channel
mode for optimal performance. See INA+ (pin A4) for detailed description. This input is terminated
to ground through a 50-Ω termination resistor. This pin can be left disconnected if not used.
INB+
M4
I
Channel B analog input positive connection. INA± is recommended for use in single channel
mode for optimal performance. The differential full-scale input voltage is determined by the
FS_RANGE_B register (see the Full-Scale Voltage (VFS) Adjustment section). This input is
terminated to ground through a 50-Ω termination resistor. The input common-mode voltage is
typically be set to 0 V (GND) and must follow the recommendations in the Recommended
Operating Conditions table. This pin can be left disconnected if not used.
INB–
M5
I
Channel B analog input negative connection. INA± is recommended for use in single channel
mode for optimal performance. See INA+ (pin A4) for detailed description. This input is terminated
to ground through a 50-Ω termination resistor. This pin can be left disconnected if not used.
NCOA0
C7
I
LSB of NCO selection control for DDC A. NCOA0 and NCOA1 select which NCO, of a possible
four NCOs, is used for digital mixing when using a complex output JMODE. The remaining
unselected NCOs continue to run to maintain phase coherency and can be swapped in by
changing the values of NCOA0 and NCOA1 (when CMODE = 1). This pin is an asynchronous
input. See the NCO Fast Frequency Hopping (FFH) and NCO Selection sections for more
information. Tie this pin to GND if not used.
NCOA1
D7
I
MSB of NCO selection control for DDC A. Tie this pin to GND if not used.
NCOB0
K7
I
LSB of NCO selection control for DDC B. NCOB0 and NCOB1 select which NCO, of a possible
four NCOs, is used for digital mixing when using a complex output JMODE. The remaining
unselected NCOs continue to run to maintain phase coherency and can be swapped in by
changing the values of NCOB0 and NCOB1 (when CMODE = 1). This pin is an asynchronous
input. See the NCO Fast Frequency Hopping (FFH) and NCO Selection sections for more
information. Tie this pin to GND if not used.
NCOB1
J7
I
MSB of NCO selection control for DDC B. Tie this pin to GND if not used.
O
Fast overrange detection status for channel A for the OVR_T0 threshold. When the analog input
exceeds the threshold programmed into OVR_T0, this status indicator goes high. The minimum
pulse duration is set by OVR_N. See the ADC Overrange Detection section for more information.
This pin can be left disconnected if not used.
O
Fast overrange detection status for channel A for the OVR_T1 threshold. When the analog input
exceeds the threshold programmed into OVR_T1, this status indicator goes high. The minimum
pulse duration is set by OVR_N. See the ADC Overrange Detection section for more information.
This pin can be left disconnected if not used.
O
Fast overrange detection status for channel B for the OVR_T0 threshold. When the analog input
exceeds the threshold programmed into OVR_T0, this status indicator goes high. The minimum
pulse duration is set by OVR_N. See the ADC Overrange Detection section for more information.
This pin can be left disconnected if not used.
O
Fast overrange detection status for channel B for the OVR_T1 threshold. When the analog input
exceeds the threshold programmed into OVR_T1, this status indicator goes high. The minimum
pulse duration is set by OVR_N. See the ADC Overrange Detection section for more information.
This pin can be left disconnected if not used.
ORA0
ORA1
ORB0
ORB1
C8
D8
K8
J8
PD
K6
I
This pin disables all analog circuits and serializer outputs when set high for temperature diode
calibration only. Do not use this pin to power down the device for power savings. Tie this pin to
GND during normal operation. For information regarding reliable serializer operation, see the
Power-Down Modes section.
SCLK
F8
I
Serial interface clock. This pin functions as the serial-interface clock input that clocks the serial
programming data in and out. The Using the Serial Interface section describes the serial interface
in more detail. Supports 1.1-V to 1.9-V CMOS levels.
SCS
E8
I
Serial interface chip select active low input. The Using the Serial Interface section describes the
serial interface in more detail. Supports 1.1-V to 1.9-V CMOS levels. This pin has a 82-kΩ pullup
resistor to VD11.
SDI
G8
I
Serial interface data input. The Using the Serial Interface section describes the serial interface in
more detail. Supports 1.1-V to 1.9-V CMOS levels.
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Pin Functions (continued)
PIN
NAME
NO.
SDO
H8
SYNCSE
C2
I/O
DESCRIPTION
O
Serial interface data output. The Using the Serial Interface section describes the serial interface
in more detail. This pin is high impedance during normal device operation. This pin outputs 1.9-V
CMOS levels during serial interface read operations. This pin can be left disconnected if not used.
I
Single-ended JESD204B SYNC signal. This input is an active low input that is used to initialize
the JESD204C serial link in 8B/10B modes when SYNC_SEL is set to 0. When toggled low this
input initiates code group synchronization (see the Code Group Synchronization (CGS) section).
After code group synchronization, this input must be toggled high to start the initial lane alignment
sequence (see the Initial Lane Alignment Sequence (ILAS) section). A differential SYNC signal
can be used instead by setting SYNC_SEL to 1 and using TMSTP± as a differential SYNC input.
Tie this pin to GND if differential SYNC (TMSTP±) is used as the JESD204B SYNC signal.
SYSREF+
K1
I
The SYSREF positive input is used to achieve synchronization and deterministic latency across
the JESD204B interface. This differential input (SYSREF+ to SYSREF–) has an internal
untrimmed 100-Ω differential termination and can be AC-coupled when SYSREF_LVPECL_EN is
set to 0. This input is self-biased when SYSREF_LVPECL_EN is set to 0. The termination
changes to 50 Ω to ground on each input pin (SYSREF+ and SYSREF–) and can be DC-coupled
when SYSREF_LVPECL_EN is set to 1. This input is not self-biased when
SYSREF_LVPECL_EN is set to 1 and must be biased externally to the input common-mode
voltage range provided in the Recommended Operating Conditions table.
SYSREF–
L1
I
SYSREF negative input
TDIODE+
K2
I
Temperature diode positive (anode) connection. An external temperature sensor can be
connected to TDIODE+ and TDIODE– to monitor the junction temperature of the device. This pin
can be left disconnected if not used.
TDIODE–
K3
I
Temperature diode negative (cathode) connection. This pin can be left disconnected if not used.
TMSTP+
B1
I
Timestamp input positive connection or differential JESD204B SYNC positive connection. This
input is a timestamp input, used to mark a specific sample, when TIMESTAMP_EN is set to 1.
This differential input is used as the JESD204B SYNC signal input when SYNC_SEL is set 1.
This input can be used as both a timestamp and differential SYNC input at the same time,
allowing feedback of the SYNC signal using the timestamp mechanism. TMSTP± uses active low
signaling when used as a JESD204B SYNC. For additional usage information, see the
Timestamp section.
TMSTP_RECV_EN must be set to 1 to use this input. This differential input (TMSTP+ to
TMSTP–) has an internal untrimmed 100-Ω differential termination and can be AC-coupled when
TMSTP_LVPECL_EN is set to 0. The termination changes to 50 Ω to ground on each input pin
(TMSTP+ and TMSTP–) and can be DC coupled when TMSTP_LVPECL_EN is set to 1. This pin
is not self-biased and therefore must be externally biased for both AC- and DC-coupled
configurations. The common-mode voltage must be within the range provided in the
Recommended Operating Conditions table when both AC and DC coupled. This pin can be left
disconnected and disabled (TMSTP_RECV_EN = 0) if SYNCSE is used for JESD204B SYNC
and timestamp is not required.
TMSTP–
C1
I
Timestamp input positive connection or differential JESD204B SYNC negative connection. This
pin can be left disconnected and disabled (TMSTP_RECV_EN = 0) if SYNCSE is used for
JESD204B SYNC and timestamp is not required.
VA11
C5, D2, D3,
D5, E5, F5,
G5, H5, J2,
J3, J5, K5
I
1.1-V analog supply
VA19
C4, D4, E2,
E3, E4, F4,
G4, H2, H3,
H4, J4, K4
I
1.9-V analog supply
VD11
C9, C10, E9,
E10, G7, H7,
H9, H10, K9,
K10
I
1.1-V digital supply
8
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6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
Supply voltage range
MIN
MAX
VA19 (2)
–0.3
2.35
VA11 (2)
–0.3
1.32
VD11 (3)
–0.3
1.32
Voltage between VD11 and VA11
–1.32
1.32
Voltage between AGND and DGND
UNIT
V
–0.1
0.1
DA[7:0]+, DA[7:0]–, DB[7:0]+, DB[7:0]–,
TMSTP+, TMSTP– (3)
–0.5
min(1.32,
VD11+0.5)
CLK+, CLK–, SYSREF+, SYSREF– (2)
–0.5
min(1.32,
VA11+0.5)
BG, TDIODE+, TDIODE– (2)
–0.5
min(2.35,
VA19+0.5)
–1
1
–0.5
VA19+0.5
Peak input current (any input except INA+, INA–, INB+, INB–)
–25
25
mA
Peak input current (INA+, INA–, INB+, INB–)
–50
50
mA
16.4
dBm
100
mA
Pin voltage range
INA+, INA–, INB+, INB–
(2)
CALSTAT, CALTRIG, NCOA0, NCOA1,
NCOB0, NCOB1, ORA0, ORA1, ORB0,
ORB1, PD, SCLK, SCS, SDI, SDO,
SYNCSE (2)
Peak RF input power (INA+, INA–, INB+, INB–)
Single-ended with ZS-SE = 50 Ω or differential
with ZS-DIFF = 100 Ω
Peak total input current (sum of absolute value of all currents forced in or out, not including
power-supply current)
Operating free-air temperature, TA
–40
Operating junction temperature, TJ
Storage temperature, Tstg
(1)
(2)
(3)
–65
V
V
85
°C
150
°C
150
°C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
Measured to AGND.
Measured to DGND.
6.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
Electrostatic discharge
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001
(1)
Charged-device model (CDM), per JEDEC specification JESD22-C101 (2)
±2500
±1000
UNIT
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
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6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
(1)
1.8
1.9
2.0
VA11, analog 1.1-V supply (1)
1.05
1.1
1.15
VD11, digital 1.1-V supply (2)
1.05
1.1
1.15
INA+, INA–, INB+, INB– (1)
–50
0
100
0
0.3
0.55
0
0.3
0.55
0.4
1.0
2.0
VA19, analog 1.9-V supply
VDD
Supply voltage range
VCMI
Input common-mode voltage
CLK+, CLK–, SYSREF+,
SYSREF– (1) (3)
TMSTP+, TMSTP–
CLK+ to CLK–, SYSREF+ to
SYSREF–, TMSTP+ to TMSTP–
Input voltage, peak-to-peak
differential
VID
(1) (4)
High-level input voltage
CALTRIG, NCOA0, NCOA1, NCOB0,
NCOB1, PD, SCLK, SCS, SDI,
SYNCSE (1)
VIL
Low-level input voltage
CALTRIG, NCOA0, NCOA1, NCOB0,
NCOB1, PD, SCLK, SCS, SDI,
SYNCSE (1)
IC_TD
Temperature diode input current
TDIODE+ to TDIODE–
CL
BG maximum load capacitance
IO
BG maximum output current
DC
Input clock duty cycle
TA
Operating free-air temperature
Operating junction temperature
Tstg
Storage temperature
(4)
(5)
(6)
(7)
0.7
V
mV
V
VPP-DIFF
V
0.45
100
30%
TJ
UNIT
1.0 (5)
INA+ to INA–, INB+ to INB–
VIH
(1)
(2)
(3)
MAX
V
µA
50%
50
pF
100
µA
70%
–40
105
–65
85
°C
(6) (7)
°C
150
°C
Measured to AGND.
Measured to DGND.
TI strongly recommends that CLK± be AC-coupled with DEVCLK_LVPECL_EN set to 0 to allow CLK± to self-bias to the optimal input
common-mode voltage for best performance. TI recommends AC-coupling for SYSREF± unless DC-coupling is required, in which case,
the LVPECL input mode must be used (SYSREF_LVPECL_EN = 1).
TMSTP± does not have internal biasing that requires TMSTP± to be biased externally whether AC-coupled with TMSTP_LVPECL_EN =
0 or DC-coupled with TMSTP_LVPECL_EN = 1.
The ADC output code saturates when VID for INA± or INB± exceeds the programmed full-scale voltage (VFS) set by FS_RANGE_A for
INA± or FS_RANGE_B for INB±.
Prolonged use above this junction temperature may increase the device failure-in-time (FIT) rate.
Tested up to 1000 hours continuous operation at Tj = 125°C. See the Absolute Maximum Ratings table for the absolute maximum
operational temperature.
6.4 Thermal Information
ADC12DJ2700
THERMAL METRIC (1)
AAV (FCBGA)
UNIT
144 PINS
RθJA
Junction-to-ambient thermal resistance
25.3
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
1.1
°C/W
RθJB
Junction-to-board thermal resistance
8.2
°C/W
ψJT
Junction-to-top characterization parameter
0.1
°C/W
ψJB
Junction-to-board characterization parameter
8.2
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
n/a
°C/W
(1)
10
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
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6.5 Electrical Characteristics: DC Specifications
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), input signal applied to INA± in single-channel modes, fIN = 248 MHz, AIN = –1 dBFS, fCLK =
maximum rated clock frequency, filtered 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise
noted); minimum and maximum values are at nominal supply voltages and over the operating free-air temperature range
provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
DC ACCURACY
Resolution
DNL
INL
Differential nonlinearity
Resolution with no missing codes
12
Maximum positive excursion from ideal step
size
0.7
Bits
LSB
Maximum negative excursion from ideal
step size
–0.3
Integral nonlinearity
±2.0
LSB
ANALOG INPUTS (INA+, INA–, INB+, INB–)
VOFF
Offset error
Default full-scale voltage, OS_CAL disabled
±0.6
mV
VOFF_ADJ
Input offset voltage
adjustment range
Available offset correction range (see
OS_CAL or OADJ_x_INx)
±55
mV
VOFF_DRIFT
Offset drift
Foreground calibration at nominal
temperature only
23
Foreground calibration at each temperature
VIN_FSR
VIN_FSR_DRIFT
Analog differential input fullscale range
Analog differential input fullscale range drift
Default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000)
750
800
Maximum full-scale voltage (FS_RANGE_A
= FS_RANGE_B = 0xFFFF)
1000
1040
Minimum full-scale voltage (FS_RANGE_A
= FS_RANGE_B = 0x2000)
480
Default FS_RANGE_A and FS_RANGE_B
setting, foreground calibration at nominal
temperature only, inputs driven by a 50-Ω
source, includes effect of RIN drift
–0.01
Default FS_RANGE_A and FS_RANGE_B
setting, foreground calibration at each
temperature, inputs driven by a 50-Ω
source, includes effect of RIN drift
0.03
VIN_FSR_MATCH
Analog differential input fullscale range matching
Matching between INA+, INA– and INB+,
INB–, default setting, dual-channel mode
RIN
Single-ended input resistance
to AGND
Each input pin is terminated to AGND,
measured at TA = 25°C
RIN_TEMPCO
Input termination linear
temperature coefficient
CIN
Single-ended input
capacitance
µV/°C
0
850
mVPP
500
%/°C
0.625%
48
50
17.6
Single-channel mode at DC
0.4
Dual-channel mode at DC
0.4
52
Ω
mΩ/°C
pF
TEMPERATURE DIODE CHARACTERISTICS (TDIODE+, TDIODE–)
ΔVBE
Temperature diode voltage
slope
Forced forward current of 100 µA. Offset
voltage (approximately 0.792 V at 0°C)
varies with process and must be measured
for each part. Offset measurement must be
done with the device unpowered or with the
PD pin asserted to minimize device selfheating. The PD pin must be asserted only
long enough to take the offset
measurement.
–1.6
mV/°C
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Electrical Characteristics: DC Specifications (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), input signal applied to INA± in single-channel modes, fIN = 248 MHz, AIN = –1 dBFS, fCLK =
maximum rated clock frequency, filtered 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise
noted); minimum and maximum values are at nominal supply voltages and over the operating free-air temperature range
provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
BAND-GAP VOLTAGE OUTPUT (BG)
VBG
Reference output voltage
IL ≤ 100 µA
1.1
V
VBG_DRIFT
Reference output temperature
IL ≤ 100 µA
drift
–64
µV/°C
CLOCK INPUTS (CLK+, CLK–, SYSREF+, SYSREF–, TMSTP+, TMSTP–)
ZT
VCM
Internal termination
Input common-mode voltage,
self-biased
Differential termination with
DEVCLK_LVPECL_EN = 0,
SYSREF_LVPECL_EN = 0, and
TMSTP_LVPECL_EN = 0
110
Ω
Single-ended termination to GND (per pin)
with DEVCLK_LVPECL_EN = 0,
SYSREF_LVPECL_EN = 0, and
TMSTP_LVPECL_EN = 0
55
Self-biasing common-mode voltage for
CLK± when AC-coupled
(DEVCLK_LVPECL_EN must be set to 0)
0.26
Self-biasing common-mode voltage for
SYSREF± when AC-coupled
(SYSREF_LVPECL_EN must be set to 0)
and with receiver enabled
(SYSREF_RECV_EN = 1)
0.29
Self-biasing common-mode voltage for
SYSREF± when AC-coupled
(SYSREF_LVPECL_EN must be set to 0)
and with receiver disabled
(SYSREF_RECV_EN = 0)
VA11
V
CL_DIFF
Differential input capacitance
Between positive and negative differential
input pins
0.1
pF
CL_SE
Single-ended input
capacitance
Each input to ground
0.5
pF
SERDES OUTPUTS (DA[7:0]+, DA[7:0]–, DB[7:0]+, DB[7:0]–)
VOD
Differential output voltage,
peak-to-peak
VCM
Output common-mode voltage AC coupled
ZDIFF
Differential output impedance
100-Ω load
550
600
650
mVPPDIFF
VD11 / 2
V
100
Ω
CMOS INTERFACE: SCLK, SDI, SDO, SCS, PD, NCOA0, NCOA1, NCOB0, NCOB1, CALSTAT, CALTRIG, ORA0, ORA1, ORB0, ORB1,
SYNCSE
IIH
High-level input current
–40
40
µA
IIL
Low-level input current
–40
40
µA
CI
Input capacitance
VOH
High-level output voltage
ILOAD = –400 µA
VOL
Low-level output voltage
ILOAD = 400 µA
12
2
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1.65
V
150
mV
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6.6 Electrical Characteristics: Power Consumption
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), input signal applied to INA± in single-channel modes, fIN = 248 MHz, AIN = –1 dBFS, fCLK =
maximum rated clock frequency, filtered 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise
noted); minimum and maximum values are at nominal supply voltages and over the operating free-air temperature range
provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
IVA19
1.9-V analog supply current
IVA11
1.1-V analog supply current
IVD11
1.1-V digital supply current
PDIS
Power dissipation
IVA19
1.9-V analog supply current
IVA11
1.1-V analog supply current
IVD11
1.1-V digital supply current
PDIS
Power dissipation
IVA19
1.9-V analog supply current
IVA11
1.1-V analog supply current
IVD11
1.1-V digital supply current
PDIS
Power dissipation
IVA19
1.9-V analog supply current
IVA11
1.1-V analog supply current
IVD11
1.1-V digital supply current
PDIS
Power dissipation
3.5
W
IVA19
1.9-V analog supply current
965
mA
IVA11
1.1-V analog supply current
439
mA
IVD11
1.1-V digital supply current
763
mA
PDIS
Power dissipation
3.2
W
Power mode 1: single-channel
mode, JMODE 1 (16 lanes, DDC
bypassed), foreground calibration
Power mode 2: single-channel
mode, JMODE 0 (8 lanes, DDC
bypassed), foreground calibration
Power mode 3: single-channel
mode, JMODE 1 (16 lanes, DDC
bypassed), background calibration
Power mode 4: dual-channel mode,
JMODE 3 (16 lanes, DDC
bypassed), background calibration
Power mode 5: dual-channel mode,
JMODE 11 (8 lanes, 4x decimation),
foreground calibration
884
mA
440
mA
529
mA
2.7
W
884
950
mA
439
600
mA
569
750
mA
2.8
3.5
mA
525
mA
544
mA
3.4
W
1242
mA
524
mA
524
mA
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6.7 Electrical Characteristics: AC Specifications (Dual-Channel Mode)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), fIN = 248 MHz, AIN = –1 dBFS, fCLK = maximum rated clock frequency, filtered 1-VPP sine-wave
clock, JMODE = 3, and background calibration (unless otherwise noted); minimum and maximum values are at nominal
supply voltages and over the operating free-air temperature range provided in the Recommended Operating Conditions table
PARAMETER
Full-power input bandwidth
(–3 dB)
FPBW
XTALK
TEST CONDITIONS
(1)
Channel-to-channel crosstalk
CER
Code error rate
NOISEDC
DC input noise standard deviation
NSD
NF
Noise spectral density, no input
signal, excludes fixed interleaving
spur (fS / 2 spur)
Noise figure, no input, ZS = 100 Ω
MIN
Foreground calibration
8.1
Background calibration
8.1
Aggressor = 400 MHz, –1 dBFS
–93
Aggressor = 3 GHz, –1 dBFS
–70
Aggressor = 6 GHz, –1 dBFS
–63
No input, foreground calibration,
excludes DC offset, includes fixed
interleaving spur (fS / 2 spur)
SNR
SNR
(1)
14
Signal-to-noise ratio, small signal,
excluding DC, HD2 to HD9 and
interleaving spurs
UNIT
GHz
dB
Errors/
sample
1.88
LSB
–151.6
Default full-scale voltage
(FS_RANGE_A = FS_RANGE_B =
0xA000) setting, foreground
calibration
–149.1
Maximum full-scale voltage
(FS_RANGE_A = 0xFFFF) setting,
foreground calibration
23.7
Default full-scale voltage
(FS_RANGE_A = 0xA000) setting,
foreground calibration
23.9
fIN = 347 MHz, AIN = –1 dBFS
56.8
fIN = 347 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A and
FS_RANGE_B setting, foreground
calibration
57.7
fIN = 2482 MHz, AIN = –1 dBFS
MAX
10–18
Maximum full-scale voltage
(FS_RANGE_A = FS_RANGE_B =
0xFFFF) setting, foreground
calibration
dBFS/Hz
dB
fIN = 997 MHz, AIN = –1 dBFS
Signal-to-noise ratio, large signal,
excluding DC, HD2 to HD9 and
interleaving spurs
TYP
56.7
52
55.8
fIN = 2482 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A and
FS_RANGE_B setting, foreground
calibration
56.6
fIN = 4997 MHz, AIN = –1 dBFS
53.5
fIN = 6397 MHz, AIN = –1 dBFS
52.3
fIN = 8197 MHz, AIN = –1 dBFS
50.8
fIN = 347 MHz, AIN = –16 dBFS
57.6
fIN = 997 MHz, AIN = –16 dBFS
57.7
fIN = 2482 MHz, AIN = –16 dBFS
57.6
fIN = 4997 MHz, AIN = –16 dBFS
57.5
fIN = 6397 MHz, AIN = –16 dBFS
57.4
fIN = 8197 MHz, AIN = –16 dBFS
57.2
dBFS
dBFS
Full-power input bandwidth (FPBW) is defined as the input frequency where the reconstructed output of the ADC has dropped 3 dB
below the power of a full-scale input signal at a low input frequency. Useable bandwidth may exceed the –3-dB, full-power input
bandwidth.
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Electrical Characteristics: AC Specifications (Dual-Channel Mode) (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), fIN = 248 MHz, AIN = –1 dBFS, fCLK = maximum rated clock frequency, filtered 1-VPP sine-wave
clock, JMODE = 3, and background calibration (unless otherwise noted); minimum and maximum values are at nominal
supply voltages and over the operating free-air temperature range provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
MIN
fIN = 347 MHz, AIN = –1 dBFS
SINAD
fIN = 2482 MHz, AIN = –1 dBFS
ENOB
51.1
fIN = 6397 MHz, AIN = –1 dBFS
49.3
fIN = 8197 MHz, AIN = –1 dBFS
47.0
fIN = 347 MHz, AIN = –1 dBFS
9.0
SFDR
SFDR
fS / 2
HD2
Spurious-free dynamic range, small
signal, excluding DC and fS / 2 fixed
spurs
fS / 2 fixed interleaving spur,
independent of input signal
2nd-order harmonic distortion
8.9
fIN = 4997 MHz, AIN = –1 dBFS
8.2
fIN = 6397 MHz, AIN = –1 dBFS
7.9
fIN = 8197 MHz, AIN = –1 dBFS
7.5
fIN = 347 MHz, AIN = –1 dBFS
70
fIN = 347 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A and
FS_RANGE_B setting, foreground
calibration
70
fIN = 2482 MHz, AIN = –1 dBFS
dBFS
9.0
8.2
fIN = 997 MHz, AIN = –1 dBFS
Spurious-free dynamic range, large
signal, excluding DC and fS / 2 fixed
spurs
55.1
fIN = 4997 MHz, AIN = –1 dBFS
fIN = 2482 MHz, AIN = –1 dBFS
UNIT
56.0
51
fIN = 997 MHz, AIN = –1 dBFS
Effective number of bits, large
signal, excluding DC and fS / 2 fixed
spurs
MAX
56.0
fIN = 997 MHz, AIN = –1 dBFS
Signal-to-noise and distortion ratio,
large signal, excluding DC and fS / 2
fixed spurs
TYP
bits
71
60
68
fIN = 2482 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A and
FS_RANGE_B setting, foreground
calibration
63
fIN = 4997 MHz, AIN = –1 dBFS
59
fIN = 6397 MHz, AIN = –1 dBFS
56
fIN = 8197 MHz, AIN = –1 dBFS
54
fIN = 347 MHz, AIN = –16 dBFS
73
fIN = 997 MHz, AIN = –16 dBFS
73
fIN = 2482 MHz, AIN = –16 dBFS
74
fIN = 4997 MHz, AIN = –16 dBFS
74
fIN = 6397 MHz, AIN = –16 dBFS
73
fIN = 8197 MHz, AIN = –16 dBFS
72
No input
–70
fIN = 347 MHz, AIN = –1 dBFS
–78
fIN = 347 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A and
FS_RANGE_B setting, foreground
calibration
–80
fIN = 997 MHz, AIN = –1 dBFS
–77
fIN = 2482 MHz, AIN = –1 dBFS
–72
fIN = 2482 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A and
FS_RANGE_B setting, foreground
calibration
–73
fIN = 4997 MHz, AIN = –1 dBFS
–67
fIN = 6397 MHz, AIN = –1 dBFS
–63
fIN = 8197 MHz, AIN = –1 dBFS
–59
dBFS
dBFS
–55
–60
dBFS
dBFS
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Electrical Characteristics: AC Specifications (Dual-Channel Mode) (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), fIN = 248 MHz, AIN = –1 dBFS, fCLK = maximum rated clock frequency, filtered 1-VPP sine-wave
clock, JMODE = 3, and background calibration (unless otherwise noted); minimum and maximum values are at nominal
supply voltages and over the operating free-air temperature range provided in the Recommended Operating Conditions table
PARAMETER
HD3
3rd-order harmonic distortion
fS / 2-fIN
SPUR
IMD3
16
fS / 2-fIN interleaving spur, signal
dependent
Worst-harmonic, 4th-order distortion
or higher
3rd-order intermodulation distortion
TEST CONDITIONS
MIN
TYP
fIN = 347 MHz, AIN = –1 dBFS
–74
fIN = 347 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A and
FS_RANGE_B setting, foreground
calibration
–71
fIN = 997 MHz, AIN = –1 dBFS
–76
fIN = 2482 MHz, AIN = –1 dBFS
–68
fIN = 2482 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A and
FS_RANGE_B setting, foreground
calibration
–63
fIN = 4997 MHz, AIN = –1 dBFS
–59
fIN = 6397 MHz, AIN = –1 dBFS
–56
fIN = 8197 MHz, AIN = –1 dBFS
–54
fIN = 347 MHz, AIN = –1 dBFS
–72
fIN = 997 MHz, AIN = –1 dBFS
–74
fIN = 2482 MHz, AIN = –1 dBFS
–75
fIN = 4997 MHz, AIN = –1 dBFS
–70
fIN = 6397 MHz, AIN = –1 dBFS
–69
fIN = 8197 MHz, AIN = –1 dBFS
–64
fIN = 347 MHz, AIN = –1 dBFS
–77
fIN = 997 MHz, AIN = –1 dBFS
–78
fIN = 2482 MHz, AIN = –1 dBFS
–78
fIN = 4997 MHz, AIN = –1 dBFS
–75
fIN = 6397 MHz, AIN = –1 dBFS
–75
fIN = 8197 MHz, AIN = –1 dBFS
–81
fIN = 347 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–83
fIN = 997 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–84
fIN = 2497 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–73
fIN = 4997 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–63
fIN = 6397 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–57
fIN = 7997 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–49
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MAX
–60
–60
–65
UNIT
dBFS
dBFS
dBFS
dBFS
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6.8 Electrical Characteristics: AC Specifications (Single-Channel Mode)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = 0xA000),
input signal applied to INA±, fIN = 248 MHz, AIN = –1 dBFS, fCLK = maximum rated clock frequency, filtered 1-VPP sine-wave
clock, JMODE = 1, and background calibration (unless otherwise noted); minimum and maximum values are at nominal
supply voltages and over the operating free-air temperature range provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
(1)
FPBW
Full-power input bandwidth
(–3 dB)
CER
Code error rate
NOISEDC
DC input noise standard deviation
NSD
NF
Noise spectral density, no input
signal, excludes fixed interleaving
spurs (fS / 2 and fS / 4 spur)
Noise figure, no input, ZS = 100 Ω
SNR
SNR
Signal-to-noise ratio, large signal,
excluding DC, HD2 to HD9 and
interleaving spurs
Signal-to-noise ratio, small signal,
excluding DC, HD2 to HD9 and
interleaving spurs
MIN
Foreground calibration
7.9
Background calibration
7.9
No input, foreground calibration,
excludes DC offset, includes fixed
interleaving spurs (fS / 2 and fS / 4
spurs), OS_CAL enabled
SINAD
(1)
GHz
1.95
LSB
Default full-scale voltage
(FS_RANGE_A = 0xA000) setting,
foreground calibration
–152.7
Maximum full-scale voltage
(FS_RANGE_A = 0xFFFF) setting,
foreground calibration
21.5
Default full-scale voltage
(FS_RANGE_A = 0xA000) setting,
foreground calibration
20.3
fIN = 347 MHz, AIN = –1 dBFS
56.8
fIN = 347 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A setting,
foreground calibration
57.6
fIN = 997 MHz, AIN = –1 dBFS
56.6
dBFS/Hz
dB
52
55.8
fIN = 2482 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A setting,
foreground calibration
56.6
fIN = 4997 MHz, AIN = –1 dBFS
53.6
fIN = 6397 MHz, AIN = –1 dBFS
52.4
fIN = 8197 MHz, AIN = –1 dBFS
50.9
fIN = 347 MHz, AIN = –16 dBFS
57.6
fIN = 997 MHz, AIN = –16 dBFS
57.4
fIN = 2482 MHz, AIN = –16 dBFS
57.4
fIN = 4997 MHz, AIN = –16 dBFS
57.4
fIN = 6397 MHz, AIN = –16 dBFS
57.4
fIN = 8197 MHz, AIN = –16 dBFS
57.2
fIN = 347 MHz, AIN = –1 dBFS
55.2
fIN = 2482 MHz, AIN = –1 dBFS
UNIT
Errors/
sample
–153.8
fIN = 2482 MHz, AIN = –1 dBFS
MAX
10–18
Maximum full-scale voltage
(FS_RANGE_A = 0xFFFF) setting,
foreground calibration
fIN = 997 MHz, AIN = –1 dBFS
Signal-to-noise and distortion ratio,
large signal, excluding DC and fS / 2
fixed spurs
TYP
dBFS
dBFS
54.3
48
53.6
fIN = 4997 MHz, AIN = –1 dBFS
50.4
fIN = 6397 MHz, AIN = –1 dBFS
48.2
fIN = 8197 MHz, AIN = –1 dBFS
45.7
dBFS
Full-power input bandwidth (FPBW) is defined as the input frequency where the reconstructed output of the ADC has dropped 3 dB
below the power of a full-scale input signal at a low input frequency. Useable bandwidth may exceed the –3-dB, full-power input
bandwidth.
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Electrical Characteristics: AC Specifications (Single-Channel Mode) (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = 0xA000),
input signal applied to INA±, fIN = 248 MHz, AIN = –1 dBFS, fCLK = maximum rated clock frequency, filtered 1-VPP sine-wave
clock, JMODE = 1, and background calibration (unless otherwise noted); minimum and maximum values are at nominal
supply voltages and over the operating free-air temperature range provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
MIN
fIN = 347 MHz, AIN = –1 dBFS
ENOB
SFDR
SFDR
fIN = 2482 MHz, AIN = –1 dBFS
8.1
fIN = 6397 MHz, AIN = –1 dBFS
7.7
fIN = 8197 MHz, AIN = –1 dBFS
7.3
fIN = 347 MHz, AIN = –1 dBFS
65
fIN = 347 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A setting,
foreground calibration
67
61
50
59
fIN = 4997 MHz, AIN = –1 dBFS
56
fIN = 6397 MHz, AIN = –1 dBFS
53
fIN = 8197 MHz, AIN = –1 dBFS
49
fIN = 347 MHz, AIN = –16 dBFS
75
fIN = 997 MHz, AIN = –16 dBFS
74
74
fIN = 8197 MHz, AIN = –16 dBFS
64
–66
67
fS / 2 fixed interleaving spur,
independent of input signal
fS / 4
fS / 4 fixed interleaving spur,
independent of input signal
No input
–70
fIN = 347 MHz, AIN = –1 dBFS
–74
fIN = 347 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A setting,
foreground calibration
–73
fIN = 997 MHz, AIN = –1 dBFS
–78
fIN = 2482 MHz, AIN = –1 dBFS
–79
fIN = 2482 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A setting,
foreground calibration
–78
fIN = 4997 MHz, AIN = –1 dBFS
–72
fIN = 6397 MHz, AIN = –1 dBFS
–61
fIN = 8197 MHz, AIN = –1 dBFS
–65
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dBFS
71
fS / 2
18
dBFS
61
Spurious free dynamic range, small f = 2482 MHz, A = –16 dBFS
IN
IN
signal, excluding DC, fS / 4 and fS / 2
f
=
4997
MHz,
A
IN
IN = –16 dBFS
fixed spurs
fIN = 6397 MHz, AIN = –16 dBFS
2nd-order harmonic distortion
!~
dBFS!~Bit
s
8.6
No input, foreground calibration,
OS_CAL disabled. Spur can be
improved by running OS_CAL.
HD2
UNIT
8.7
7.7
fIN = 4997 MHz, AIN = –1 dBFS
fIN = 997 MHz, AIN = –1 dBFS
Spurious free dynamic range, large
fIN = 2482 MHz, AIN = –1 dBFS
signal, excluding DC, fS / 4 and fS / 2
fIN = 2482 MHz, AIN = –1 dBFS,
fixed spurs
maximum FS_RANGE_A setting,
foreground calibration
MAX
8.9
fIN = 997 MHz, AIN = –1 dBFS
Effective number of bits, large
signal, excluding DC and fS / 2 fixed
spurs
TYP
dBFS
–55
–60
dBFS
dBFS
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Electrical Characteristics: AC Specifications (Single-Channel Mode) (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = 0xA000),
input signal applied to INA±, fIN = 248 MHz, AIN = –1 dBFS, fCLK = maximum rated clock frequency, filtered 1-VPP sine-wave
clock, JMODE = 1, and background calibration (unless otherwise noted); minimum and maximum values are at nominal
supply voltages and over the operating free-air temperature range provided in the Recommended Operating Conditions table
PARAMETER
HD3
fS / 2 – fIN
fS / 4 ± fIN
SPUR
IMD3
3rd-order harmonic distortion
fS / 2 – fIN interleaving spur, signal
dependent
fS / 4 ± fIN interleaving spurs, signal
dependent
Worst-harmonic, 4th-order distortion
or higher
3rd-order intermodulation distortion
TEST CONDITIONS
MIN
TYP
fIN = 347 MHz, AIN = –1 dBFS
–71
fIN = 347 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A setting,
foreground calibration
–69
fIN = 997 MHz, AIN = –1 dBFS
–72
fIN = 2482 MHz, AIN = –1 dBFS
–68
fIN = 2482 MHz, AIN = –1 dBFS,
maximum FS_RANGE_A setting,
foreground calibration
–62
fIN = 4997 MHz, AIN = –1 dBFS
–61
fIN = 6397 MHz, AIN = –1 dBFS
–59
fIN = 8197 MHz, AIN = –1 dBFS
–56
fIN = 347 MHz, AIN = –1 dBFS
–65
fIN = 997 MHz, AIN = –1 dBFS
–61
fIN = 2482 MHz, AIN = –1 dBFS
–59
fIN = 4997 MHz, AIN = –1 dBFS
–56
fIN = 6397 MHz, AIN = –1 dBFS
–53
fIN = 8197 MHz, AIN = –1 dBFS
–49
fIN = 347 MHz, AIN = –1 dBFS
–75
fIN = 997 MHz, AIN = –1 dBFS
–72
fIN = 2482 MHz, AIN = –1 dBFS
–75
fIN = 4997 MHz, AIN = –1 dBFS
–69
fIN = 6397 MHz, AIN = –1 dBFS
–69
fIN = 8197 MHz, AIN = –1 dBFS
–65
fIN = 347 MHz, AIN = –1 dBFS
–75
fIN = 997 MHz, AIN = –1 dBFS
–78
fIN = 2482 MHz, AIN = –1 dBFS
–78
fIN = 4997 MHz, AIN = –1 dBFS
–72
fIN = 6397 MHz, AIN = –1 dBFS
–72
fIN = 8197 MHz, AIN = –1 dBFS
–79
fIN = 347 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–90
fIN = 997 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–79
fIN = 2497 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–73
fIN = 4997 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–63
fIN = 6397 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–58
fIN = 7997 MHz ± 2.5 MHz,
AIN = –7 dBFS per tone
–51
MAX
–60
–50
–60
–65
UNIT
dBFS
dBFS
dBFS
dBFS
dBFS
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6.9 Timing Requirements
MIN
NOM
MAX
UNIT
2700
MHz
DEVICE (SAMPLING) CLOCK (CLK+, CLK–)
Input clock frequency (CLK+, CLK–), both single-channel and dual-channel
modes (1)
fCLK
800
SYSREF (SYSREF+, SYSREF–)
tINV(SYSREF)
Width of invalid SYSREF capture region of CLK± period, indicating setup or
hold time violation, as measured by SYSREF_POS status register (2)
tINV(TEMP)
48
ps
Drift of invalid SYSREF capture region over temperature, positive number
indicates a shift toward MSB of SYSREF_POS register
0
ps/°C
tINV(VA11)
Drift of invalid SYSREF capture region over VA11 supply voltage, positive
number indicates a shift toward MSB of SYSREF_POS register
0.36
ps/mV
tSTEP(SP)
Delay of SYSREF_POS LSB
SYSREF_ZOOM = 0
77
SYSREF_ZOOM = 1
24
t(PH_SYS)
Minimum SYSREF± assertion duration after SYSREF± rising edge event
4
ns
t(PL_SYS)
Minimum SYSREF± de-assertion duration after SYSREF± falling edge
event
1
ns
ps
JESD204B SYNC TIMING (SYNCSE OR TMSTP±)
tH(SYNCSE)
Minimum hold time from multiframe boundary
(SYSREF rising edge captured high) to deassertion of JESD204B SYNC signal (SYNCSE if
SYNC_SEL = 0 or TMSTP± if SYNC_SEL = 1) for
NCO synchronization (NCO_SYNC_ILA = 1)
JMODE = 0, 2, 4, 6,
10, 13, or 15
21
JMODE = 1, 3, 5, 7, 9,
11, 14, or 16
17
JMODE = 12, 17, or 18
9
JMODE = 0, 2, 4, 6,
10, 13, or 15
tSU(SYNCSE)
Minimum setup time from de-assertion of
JESD204B SYNC signal (SYNCSE if SYNC_SEL
= 0 or TMSTP± if SYNC_SEL = 1) to multiframe
boundary (SYSREF rising edge captured high) for
NCO synchronization (NCO_SYNC_ILA = 1)
t(SYNCSE)
SYNCSE minimum assertion time to trigger link resynchronization
tCLK
cycles
–2
JMODE = 1, 3, 5, 7, 9,
11, 14, or 16
2
JMODE = 12, 17, or 18
10
4
tCLK
cycles
Frames
SERIAL PROGRAMMING INTERFACE (SCLK, SDI, SCS)
fCLK(SCLK)
Maximum serial clock frequency
t(PH)
Minimum serial clock high value pulse duration
32
ns
t(PL)
Minimum serial clock low value pulse duration
32
ns
tSU(SCS)
Minimum setup time from SCS to rising edge of SCLK
30
ns
tH(SCS)
Minimum hold time from rising edge of SCLK to SCS
3
ns
tSU(SDI)
Minimum setup time from SDI to rising edge of SCLK
30
ns
tH(SDI)
Minimum hold time from rising edge of SCLK to SDI
3
ns
(1)
(2)
20
15.625
MHz
Unless functionally limited to a smaller range in Table 19 based on programmed JMODE.
Use SYSREF_POS to select an optimal SYSREF_SEL value for the SYSREF capture, see the SYSREF Position Detector and
Sampling Position Selection (SYSREF Windowing) section for more information on SYSREF windowing. The invalid region, specified by
tINV(SYSREF), indicates the portion of the CLK± period (tCLK), as measured by SYSREF_SEL, that may result in a setup and hold violation.
Verify that the timing skew between SYSREF± and CLK± over system operating conditions from the nominal conditions (that used to
find optimal SYSREF_SEL) does not result in the invalid region occurring at the selected SYSREF_SEL position in SYSREF_POS,
otherwise a temperature dependent SYSREF_SEL selection may be needed to track the skew between CLK± and SYSREF±.
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6.10 Switching Characteristics
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), input signal applied to INA± in single-channel modes, fIN = 248 MHz, AIN = –1 dBFS, fCLK =
maximum rated clock frequency, filtered 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise
noted); minimum and maximum values are at nominal supply voltages and over the operating free-air temperature range
provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
DEVICE (SAMPLING) CLOCK (CLK+, CLK–)
tAD
Sampling (aperture) delay from the
CLK± rising edge (dual-channel
mode) or rising and falling edge
(single-channel mode) to sampling
instant
tTAD(MAX)
Maximum tAD adjust programmable
delay, not including clock inversion
(TAD_INV = 0)
tTAD(STEP)
tAJ
tAD adjust programmable delay step
size
Aperture jitter, rms
TAD_COARSE = 0x00, TAD_FINE
= 0x00, and TAD_INV = 0
360
ps
Coarse adjustment
(TAD_COARSE = 0xFF)
289
ps
Fine adjustment (TAD_FINE =
0xFF)
4.9
ps
1.13
ps
Fine adjustment (TAD_FINE)
19
fs
Minimum tAD adjust coarse setting
(TAD_COARSE = 0x00, TAD_INV
= 0)
50
Maximum tAD adjust coarse setting
(TAD_COARSE = 0xFF) excluding
TAD_INV (TAD_INV = 0)
(1)
Coarse adjustment
(TAD_COARSE)
fs
70
SERIAL DATA OUTPUTS (DA[7:0]+, DA[7:0]–, DB[7:0]+, DB[7:0]–)
fSERDES
Serialized output bit rate
UI
Serialized output unit interval
tTLH
Low-to-high transition time
(differential)
20% to 80%, PRBS-7 test pattern,
12.8 Gbps, SER_PE = 0x04
37
ps
tTHL
High-to-low transition time
(differential)
20% to 80%, PRBS-7 test pattern,
12.8 Gbps, SER_PE = 0x04
37
ps
DDJ
Data dependent jitter, peak-to-peak
PRBS-7 test pattern, 12.8 Gbps,
SER_PE = 0x04, JMODE = 2
7.8
ps
RJ
Random jitter, RMS
PRBS-7 test pattern, 12.8 Gbps,
SER_PE = 0x04, JMODE = 2
1.1
ps
PRBS-7 test pattern, 12.8 Gbps,
SER_PE = 0x04, JMODE = 0, 2
25
PRBS-7 test pattern, 6.4 Gbps,
SER_PE = 0x04, JMODE = 1, 3
21
PRBS-7 test pattern, 8 Gbps,
SER_PE = 0x04, JMODE = 4, 5, 6,
7
28
PRBS-7 test pattern, 8 Gbps,
SER_PE = 0x04, JMODE = 9
35
PRBS-7 test pattern, 8 Gbps,
SER_PE = 0x04, JMODE = 10, 11
40
PRBS-7 test pattern, 3.2 Gbps,
SER_PE = 0x04, JMODE = 12
26
PRBS-7 test pattern, 8 Gbps,
SER_PE = 0x04, JMODE = 13, 14
39
PRBS-7 test pattern, 8 Gbps,
SER_PE = 0x04, JMODE = 15, 16
34
TJ
(1)
Total jitter, peak-to-peak, with
gaussian portion defined with respect
to a BER = 1e-15 (Q = 7.94)
1
12.8
Gbps
78.125
1000
ps
ps
tAJ increases because of additional attenuation on the internal clock path.
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Switching Characteristics (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), input signal applied to INA± in single-channel modes, fIN = 248 MHz, AIN = –1 dBFS, fCLK =
maximum rated clock frequency, filtered 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise
noted); minimum and maximum values are at nominal supply voltages and over the operating free-air temperature range
provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
ADC CORE LATENCY
tADC
Deterministic delay from the CLK±
edge that samples the reference
sample to the CLK± edge that
samples SYSREF going high (2)
JMODE = 0
–8.5
JMODE = 1
–20.5
JMODE = 2
–9
JMODE = 3
–21
JMODE = 4
–4.5
JMODE = 5
–24.5
JMODE = 6
–5
JMODE = 7
–25
JMODE = 9
60
JMODE = 10
140
JMODE = 11
136
JMODE = 12
120
JMODE = 13
232
JMODE = 14
232
JMODE = 15
446
JMODE = 16
430
JMODE = 17
–48.5
JMODE = 18
-49
tCLK cycles
JESD204B AND SERIALIZER LATENCY
tTX
(2)
(3)
22
Delay from the CLK± rising edge that
samples SYSREF high to the first bit
of the multiframe on the JESD204B
serial output lane corresponding to
the reference sample of tADC (3)
JMODE = 0
72
84
JMODE = 1
119
132
JMODE = 2
72
84
JMODE = 3
119
132
JMODE = 4
67
80
JMODE = 5
106
119
JMODE = 6
67
80
JMODE = 7
106
119
JMODE = 9
106
119
JMODE = 10
67
80
JMODE = 11
106
119
JMODE = 12
213
225
JMODE = 13
67
80
JMODE = 14
106
119
JMODE = 15
67
80
JMODE = 16
106
119
JMODE = 17
195
208
JMODE = 18
195
208
tCLK cycles
tADC is an exact, unrounded, deterministic delay. The delay can be negative if the reference sample is sampled after the SYSREF high
capture point, in which case the total latency is smaller than the delay given by tTX.
The values given for tTX include deterministic and non-deterministic delays. Over process, temperature, and voltage, the delay will vary.
JESD204B accounts for these variations when operating in subclass-1 mode in order to achieve deterministic latency. Proper receiver
RBD values must be chosen such that the elastic buffer release point does not occur within the invalid region of the local multiframe
clock (LMFC) cycle.
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Switching Characteristics (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = 1.1 V, VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A =
FS_RANGE_B = 0xA000), input signal applied to INA± in single-channel modes, fIN = 248 MHz, AIN = –1 dBFS, fCLK =
maximum rated clock frequency, filtered 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise
noted); minimum and maximum values are at nominal supply voltages and over the operating free-air temperature range
provided in the Recommended Operating Conditions table
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
SERIAL PROGRAMMING INTERFACE (SDO)
t(OZD)
Maximum delay from the falling edge of the 16th SCLK cycle during read
operation for SDO transition from tri-state to valid data
7
ns
t(ODZ)
Maximum delay from the SCS rising edge for SDO transition from valid
data to tri-state
7
ns
t(OD)
Maximum delay from the falling edge of the 16th SCLK cycle during read
operation to SDO valid
12
ns
S1
S0
tAD
S2
tADC
tCLK
CLK+
CLK±
SYSREF+
SYSREF±
tSU(SYSREF)
tH(SYSREF)
tTX
Start of Multi-Frame
DA0+/±(1)
(1)
S0
S1
S2
Only the SerDes lane DA0± is shown, but DA0± is representative of all lanes. The number of output lanes used and
bit-packing format is dependent on the programmed JMODE value.
Figure 1. ADC Timing Diagram
CLK+
CLK±
SYSREF+
SYSREF±
LMFC(1)
(Internal)
One multi-frame
One multi-frame
tSU(SYNCSE)
tH(SYNCSE)
SYNCSE
(SYNC_SEL = 0)
TMSTP+/±
(SYNC_SEL = 1)
tTX
DA0+/±(2)
Start of ILAS
/R
(2)
The internal LMFC is assumed to be aligned with the CLK± rising edge that captures the SYSREF± high value.
(3)
Only SerDes lane DA0± is shown, but DA0± is representative of all lanes. All lanes output /R at approximately the
same point in time. The number of lanes is dependent on the programmed JMODE value.
Figure 2. SYNCSE and TMSTP± Timing Diagram for NCO Synchronization
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1st clock
16th clock
24th clock
SCLK
tSU(SCS)
tH(SCS)
t(PH)
t(PL)
tH(SCS)
tSU(SCS)
t(PH) + t(PL) = t(P) = 1 / ¦CLK(SCLK)
SCS
tSU(SDI)
tSU(SDI) tH(SDI)
SDI
D7
D0
Write Command
COMMAND FIELD
SDO
D1
tH(SDI)
t(OD)
Hi-Z
D7
t(OZD)
D1
D0
Read Command
Hi-Z
t(ODZ)
Figure 3. Serial Interface Timing
24
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6.11 Typical Characteristics
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
9.5
BG Calibration
FG Calibration
9
Effective Number of Bits (Bits)
Effective Number of Bits (Bits)
9.5
8.5
8
7.5
7
6.5
BG Calibration
FG Calibration
9
8.5
8
7.5
7
6.5
0
2000
4000
6000
fIN (MHz)
8000
10000
0
2000
D010
JMODE3, fS = 2700 MSPS, foreground (FG) and background (BG)
calibration
10000
D002
Figure 5. ENOB vs Input Frequency
75
75
SNR
SINAD
SFDR
70
SNR
SINAD
SFDR
70
65
Magnitude (dBFS)
Magnitude (dBFS)
8000
JMODE1, fS = 5400 MSPS, FG and BG calibration
Figure 4. ENOB vs Input Frequency
60
55
50
65
60
55
50
45
45
40
40
0
2000
4000
6000
fIN (MHz)
8000
0
10000
2000
D131
JMODE3, fS = 2700 MSPS, FG calibration
8000
10000
D129
Figure 7. SNR, SINAD, SFDR vs Input Frequency
-50
-55
-55
-60
-60
Magnitude (dBFS)
-50
-65
-70
-75
HD2
HD3
THD
-80
4000
6000
fIN (MHz)
JMODE1, fS = 5400 MSPS, FG calibration
Figure 6. SNR, SINAD, SFDR vs Input Frequency
Magnitude (dBFS)
4000
6000
fIN (MHz)
-65
-70
-75
HD2
HD3
THD
-80
-85
-85
0
2000
4000
6000
fIN (MHz)
8000
10000
0
2000
D132
4000
6000
fIN (MHz)
8000
10000
JMODE3, fS = 2700 MSPS, FG calibration
JMODE1, fS = 5400 MSPS, FG calibration
Figure 8. HD2, HD3, THD vs Input Frequency
Figure 9. HD2, HD3, THD vs Input Frequency
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Typical Characteristics (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
75
75
SNR
SINAD
SFDR
SNR
SINAD
SFDR
70
65
Magnitude (dBFS)
Magnitude (dBFS)
70
60
55
50
45
65
60
55
50
45
40
40
0
2000
4000
6000
fIN (MHz)
8000
10000
0
2000
D009
JMODE3, fS = 2700 MSPS, BG calibration
-55
-55
-60
-60
-65
-70
-75
HD2
HD3
THD
D001
-65
-70
-75
HD2
HD3
THD
-80
-85
-85
0
2000
4000
6000
fIN (MHz)
8000
10000
0
2000
D011
JMODE3, fS = 2700 MSPS, BG calibration
Figure 12. HD2, HD3, THD vs Input Frequency
8000
10000
D003
Figure 13. HD2, HD3, THD vs Input Frequency
Effective Number of Bits (Bits)
9.5
9.25
9
8.75
8.5
800
4000
6000
fIN (MHz)
JMODE1, fS = 5400 MSPS, BG calibration
9.5
Effective Number of Bits (Bits)
10000
Figure 11. SNR, SINAD, SFDR vs Input Frequency
-50
Magnitude (dBFS)
Magnitude (dBFS)
Figure 10. SNR, SINAD, SFDR vs Input Frequency
1200
1600
2000
fS (MSPS)
2400
2700
9.25
9
8.75
8.5
1600
2400
D013
JMODE3, fIN = 347 MHz, BG calibration
3200
4000
fS (MSPS)
4800
5400
D005
JMODE1, fIN = 347 MHz, BG calibration
Figure 14. ENOB vs Sampling Rate
26
8000
JMODE1, fS = 5400 MSPS, BG calibration
-50
-80
4000
6000
fIN (MHz)
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Figure 15. ENOB vs Sampling Rate
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Typical Characteristics (continued)
75
75
70
70
65
65
Magnitude (dBFS)
Magnitude (dBFS)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
60
55
50
SNR
SINAD
SFDR
45
40
800
1200
1600
2000
fS (MSPS)
2400
60
55
50
SNR
SINAD
SFDR
45
40
1600
2700
JMODE3, fIN = 347 MHz, BG calibration
Figure 16. SNR, SINAD, SFDR vs Sampling Rate
4800
5400
D004
Figure 17. SNR, SINAD, SFDR vs Sampling Rate
-55
HD2
HD3
THD
-60
HD2
HD3
THD
-60
-65
Magnitude (dBFS)
Magnitude (dBFS)
3200
4000
fS (MSPS)
JMODE1, fIN = 347 MHz, BG calibration
-55
-70
-75
-80
-85
-65
-70
-75
-80
-85
-90
800
1200
1600
2000
fS (MSPS)
2400
-90
1600
2700
2400
D014
JMODE3, fIN = 347 MHz, BG calibration
3200
4000
fS (MSPS)
4800
5400
D006
JMODE1, fIN = 347 MHz, BG calibration
Figure 18. HD2, HD3, THD vs Sampling Rate
Figure 19. HD2, HD3, THD vs Sampling Rate
0
0
-20
-20
Magnitude (dBFS)
Magnitude (dBFS)
2400
D012
-40
-60
-80
-100
-40
-60
-80
-100
-120
-120
0
337.5
675
Frequency (MHz)
1012.5
1350
0
675
D139
JMODE3, fIN = 350 MHz, FG calibration, SNR = 56.7 dBFS,
SFDR = 68.0 dBFS, ENOB = 9.00 bits
Figure 20. Single-Tone FFT at AIN = –1 dBFS
1350
Frequency (MHz)
2025
2700
D134
JMODE1, fIN = 350 MHz, FG calibration, SNR = 56.6 dBFS,
SFDR = 70.0 dBFS, ENOB = 8.98 bits
Figure 21. Single-Tone FFT at AIN = –1 dBFS
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Typical Characteristics (continued)
0
0
-20
-20
Magnitude (dBFS)
Magnitude (dBFS)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
-40
-60
-80
-100
-40
-60
-80
-100
-120
-120
0
337.5
675
Frequency (MHz)
1012.5
1350
0
JMODE3, fIN = 2400 MHz, FG calibration, SNR = 55.7 dBFS,
SFDR = 71.7 dBFS, ENOB = 8.87 bits
-20
-20
Magnitude (dBFS)
Magnitude (dBFS)
0
-60
-80
2700
D135
-40
-60
-80
-100
-100
-120
-120
0
337.5
675
Frequency (MHz)
1012.5
0
1350
675
D141
JMODE3, fIN = 5000 MHz, FG calibration, SNR = 53.8 dBFS,
SFDR = 59.3 dBFS, ENOB = 8.26 bits
-20
-20
Magnitude (dBFS)
0
-60
-80
-100
2025
2700
D136
Figure 25. Single-Tone FFT at AIN = –1 dBFS
0
-40
1350
Frequency (MHz)
JMODE1, fIN = 5000 MHz, FG calibration, SNR = 54 dBFS,
SFDR = 55.0 dBFS, ENOB = 8.09 bits
Figure 24. Single-Tone FFT at AIN = –1 dBFS
Magnitude (dBFS)
2025
Figure 23. Single-Tone FFT at AIN = –1 dBFS
0
-40
1350
Frequency (MHz)
JMODE1, fIN = 2400 MHz, FG calibration, SNR = 55.8 dBFS,
SFDR = 69.3 dBFS, ENOB = 8.90 bits
Figure 22. Single-Tone FFT at AIN = –1 dBFS
-40
-60
-80
-100
-120
-120
0
337.5
675
Frequency (MHz)
1012.5
1350
0
675
D145
JMODE3, fIN = 8200 MHz, FG calibration, SNR = 51.4 dBFS,
SFDR = 54.0 dBFS, ENOB = 7.62 bits
Figure 26. Single-Tone FFT at AIN = –1 dBFS
28
675
D140
1350
Frequency (MHz)
2025
2700
D144
JMODE1, fIN = 8200 MHz, FG calibration, SNR = 51.5 dBFS,
SFDR = 47.2 dBFS, ENOB = 7.16 bits
Figure 27. Single-Tone FFT at AIN = –1 dBFS
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Typical Characteristics (continued)
0
0
-20
-20
Magnitude (dBFS)
Magnitude (dBFS)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
-40
-60
-80
-40
-60
-80
-100
-100
-120
-120
0
337.5
675
Frequency (MHz)
1012.5
0
1350
JMODE3, fIN = 8200 MHz, FG calibration, SNR = 57.1 dBFS,
SFDR = 74.5 dBFS, ENOB = 9.12 bits
Figure 28. Single-Tone FFT at AIN = –16 dBFS
2025
2700
D137
Figure 29. Single-Tone FFT at AIN = –16 dBFS
4
Integral Non-Linearity (LSB)
0.5
0.25
0
-0.25
-0.5
2
0
-2
-4
-0.75
0
0
4095
Code
4095
Code
D048
JMODE1, fS = 5400 MSPS, FG calibration
Figure 30. DNL vs Code
Figure 31. INL vs Code
-55
SNR
SINAD
SFDR
70
HD2
HD3
THD
-60
Magnitude (dBFS)
65
60
55
50
-65
-70
-75
-80
-85
45
40
-75
D049
JMODE1, fS = 5400 MSPS, FG calibration
75
Magnitude (dBFS)
1350
Frequency (MHz)
JMODE1, fIN = 8200 MHz, FG calibration, SNR = 57.0 dBFS,
SFDR = 61.5 dBFS, ENOB = 8.89 bits
0.75
Differential Non-Linearity (LSB)
675
D142
-50
-25
0
25
50
75
Ambient Temperature (°C)
100
125
-90
-75
-50
D039
JMODE1, fS = 5400 MSPS, fIN = 2400 MHz, BG calibration
Figure 32. SNR, SINAD, SFDR vs Temperature
-25
0
25
50
75
Ambient Temperature (°C)
100
125
D041
JMODE1, fS = 5400 MSPS, fIN = 2400 MHz, BG calibration
Figure 33. HD2, HD3, THD vs Temperature
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Typical Characteristics (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
9.5
FG Calibration at Each Temperature
FG Calibration at 25°C
BG Calibration
FG Calibration at Each Temperature
8.75
Effective Number of Bits (Bits)
Effective Number of Bits (Bits)
9
8.5
8.25
8
7.75
7.5
-75
-50
-25
0
25
50
75
Ambient Temperature (°C)
100
9
8.5
8
7.5
-75
125
100
125
D121
74
62
FG Calibration at Each Temperature
FG Calibration at 25°C
60
Spurious-Free Dynamic Range (dBFS)
Signal-to-Noise Ratio (dBFS)
0
25
50
75
Ambient Temperature (°C)
Figure 35. ENOB vs Temperature and Calibration Type
Figure 34. ENOB vs Temperature and Calibration Type
58
56
54
52
50
-75
-50
-25
0
25
50
75
Ambient Temperature (°C)
100
FG Calibration at Each Temperature
FG Calibration at 25°C
70
66
62
58
54
-75
125
-25
0
25
50
75
Ambient Temperature (°C)
100
125
D064
JMODE1, fIN = 600 MHz, fS = 5400 MSPS
Figure 36. SNR vs Temperature and Calibration Type
Figure 37. SFDR vs Temperature and Calibration Type
-55
-45
Third-Order Harmonic Distortion (dBFS)
FG Calibration at Each Temperature
FG Calibration at 25°C
-60
-65
-70
-75
-80
-85
-90
-75
-50
D063
JMODE1, fIN = 600 MHz, fS = 5400 MSPS
Second-Order Harmonic Distortion (dBFS)
-25
JMODE1, fIN = 600 MHz, fS = 5400 MSPS
JMODE1, fIN = 2400 MHz, fS = 5400 MSPS
-50
-25
0
25
50
75
Ambient Temperature (°C)
100
125
FG Calibration at Each Temperature
FG Calibration at 25°C
-50
-55
-60
-65
-70
-75
-80
-75
-50
D119
JMODE1, fIN = 600 MHz, fS = 5400 MSPS
Figure 38. HD2 vs Temperature and Calibration Type
30
-50
D040
-25
0
25
50
75
Ambient Temperature (°C)
100
125
D120
JMODE1, fIN = 600 MHz, fS = 5400 MSPS
Figure 39. HD3 vs Temperature and Calibration Type
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Typical Characteristics (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
66
9.2
Effective Number of Bits (Bits)
64
Magnitude (dBFS)
62
60
58
56
54
SNR
SINAD
SFDR
52
50
-5
-2.5
0
Supply Voltage (%)
2.5
9
8.8
8.6
8.4
8.2
-5
5
-2.5
JMODE1, fS = 5400 MSPS, fIN = 600 MHz, FG calibration
Figure 40. SNR, SINAD, SFDR vs Supply Voltage
5
D037
Figure 41. ENOB vs Supply Voltage
85
HD2
HD3
THD
-60
80
75
-65
Magnitude (dBFS)
Magnitude (dBFS)
2.5
JMODE1, fS = 5400 MSPS, fIN = 600 MHz, FG calibration
-55
-70
-75
70
65
60
-80
55
-85
50
SNR
SINAD
SFDR
45
-90
-5
-2.5
0
Supply Voltage (%)
2.5
1
5
D038
2
3
4
5
6
7 8 9 10 11 12 13 14 15 16
Decimation Factor
D035
fS = 2700 MSPS, fIN = 2400 MHz, FG calibration
JMODE1, fS = 5400 MSPS, fIN = 600 MHz, FG calibration
Figure 43. SNR, SINAD, SFDR vs Decimation Factor
Figure 42. HD2, HD3, THD vs Supply Voltage
1.2
11
1
10.5
Supply Current (A)
Effective Number of Bits (Bits)
0
Supply Voltage (%)
D036
10
9.5
0.8
0.6
0.4
9
fIN = 2400 MHz
fIN = 600 MHz
8.5
1
2
3
4
5
6
7 8 9 10 11 12 13 14 15 16
Decimation Factor
D133
fS = 2700 MSPS, FG calibration
IA19
IA11
ID11
0.2
0
1600
2400
3200
4000
fS (MSPS)
4800
5400
D007
JMODE1, fIN = 347 MHz, FG calibration
Figure 44. ENOB vs Decimation Factor
Figure 45. Supply Current vs Sampling Rate
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Typical Characteristics (continued)
3.2
1.2
3
1
Supply Current (A)
Power Consumption (W)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
2.8
2.6
2.4
2.2
0.8
0.6
0.4
2
1600
2400
3200
4000
fS (MSPS)
4800
0
800
5400
2400
1.2
3
1
2.8
2.6
2.4
2.2
D015
0.8
0.6
0.4
IA19
IA11
ID11
0.2
2
800
1200
1600
2000
fS (MSPS)
2700
Figure 47. Supply Current vs Sampling Rate
3.2
Supply Current (A)
Power Consumption (W)
1600
2000
fS (MSPS)
JMODE3, fIN = 347 MHz, FG calibration
Figure 46. Power Consumption vs Sampling Rate
2400
0
-75
2700
-50
-25
D016
JMODE3, fIN = 347 MHz, FG calibration
0
25
50
75
Ambient Temperature (°C)
100
125
D047
JMODE1, fS = 5400 MSPS, fIN = 2400 MHz, BG calibration
Figure 48. Power Consumption vs Sampling Rate
Figure 49. Supply Current vs Temperature
4
1
3.75
0.9
3.5
0.8
Supply Current (A)
Power Consumption (W)
1200
D008
JMODE1, fIN = 347 MHz, FG calibration
3.25
3
2.75
0.7
0.6
0.5
0.4
2.5
2.25
-50
-25
0
25
50
75
Ambient Temperature (°C)
100
IA19
IA11
ID11
0.3
BG Calibration
FG Calibration
2
-75
125
0.2
-5
-2.5
D046
JMODE1, fS = 5400 MSPS, fIN = 2400 MHz, BG calibration
Figure 50. Power Consumption vs Temperature
32
IA19
IA11
ID11
0.2
0
Supply Voltage (%)
2.5
5
D045
JMODE1, fS = 5400 MSPS, FG calibration
Figure 51. Supply Current vs Supply Voltage
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Typical Characteristics (continued)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
1.2
1.1
3
Supply Current (A)
Power Consumption (W)
3.2
2.8
1
0.9
2.6
0.8
2.4
-5
-2.5
0
Supply Voltage (%)
2.5
FG Calibration
BG Calibration
LPBG Calibration
0.7
800
5
1200
JMODE1, fS = 5400 MSPS, FG calibration
0.6
0.6
Supply Current (A)
0.8
0.4
0.2
D123
0.4
0.2
FG Calibration
BG Calibration
LPBG Calibration
1200
1600
2000
fCLK (MHz)
2400
FG Calibration
BG Calibration
LPBG Calibration
0
800
2700
1200
1600
2000
fCLK (MHz)
D124
JMODE0, fIN = 607 MHz
2400
2700
D117
JMODE0, fIN = 607 MHz
Figure 54. IA11 Supply Current vs Clock Frequency
Figure 55. ID11 Supply Current vs Clock Frequency
4
1.5
FG Calibration
BG Calibration
LPBG Calibration
IA19
IA11
ID11
1.25
3.5
Supply Current (A)
Power Consumption (W)
2700
Figure 53. IA19 Supply Current vs Clock Frequency
0.8
0
800
2400
JMODE0, fIN = 607 MHz
Figure 52. Power Consumption vs Supply Voltage
Supply Current (A)
1600
2000
fCLK (MHz)
D044
3
1
0.75
0.5
2.5
0.25
2
800
0
1200
1600
2000
fCLK (MHz)
2400
2700
0
2
D118
JMODE0, fIN = 607 MHz
4
6
8
10
JMODE
12
14
16
18
D034
fIN = 2400 MHz, fCLK = 2700 MHz, FG calibration
Figure 56. Power Consumption vs Clock Frequency
Figure 57. Supply Current vs JMODE
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Typical Characteristics (continued)
1.5
4
1.25
3.75
Power Consumption (W)
Supply Current (A)
typical values at TA = 25°C, VA19 = 1.9 V, VA11 = VD11 = 1.1 V, default full-scale voltage (FS_RANGE_A = FS_RANGE_B
= 0xA000), input signal applied to INA± in single-channel modes, fIN = 347 MHz, AIN = –1 dBFS, fCLK = maximum-rated clock
frequency, filtered, 1-VPP sine-wave clock, JMODE = 1, and background calibration (unless otherwise noted); SNR results
exclude DC, HD2 to HD9 and interleaving spurs; SINAD, ENOB, and SFDR results exclude DC and fixed-frequency
interleaving spurs
1
0.75
0.5
IA19
IA11
ID11
0.25
FG Calibration
BG Calibration
LPBG Calibration
3.5
3.25
3
2.75
0
2.5
0
2
4
6
8
10
JMODE
12
14
16
18
0
2
4
D122
fIN = 2400 MHz, fCLK = 2700 MHz, BG calibration
6
8
10
JMODE
12
14
16
18
D033
fIN = 2400 MHz, fCLK = 2700 MHz
Figure 58. Supply Current vs JMODE
Figure 59. Power Consumption vs JMODE
2200
4000
3500
2000
2500
Sample Value
Sample Value
3000
Zoomed Area
in Following Plot
2000
1500
1000
1800
1600
500
0
0
5000
10000
15000 20000 25000
Sample Number
30000
1400
14800
35000
15200
D125
JMODE0, fCLK = 3200 MHz, fIN = 3199.9 MHz
15600
Sample Number
16000
16400
D126
JMODE0, fCLK = 3200 MHz, fIN = 3199.9 MHz
Figure 60. Background Calibration Core Transition
(AC Signal) (1)
Figure 61. Background Calibration Core Transition
(AC Signal Zoomed)(1)
4096
500
-0.35V Differential
3584
+0.35 V Differential
-0.35 V Differential
0 V Differential
400
Sample Value
Sample Value
3072
2560
2048
1536
1024
Zoomed Area
in Following Plot
300
200
100
512
0
0
1000
2000
3000 4000 5000
Sample Number
6000
7000
8000
Figure 62. Background Calibration Core Transition
(DC Signal)(1)
34
1700
D127
JMODE0, fCLK = 3200 MHz, DC input
(1)
0
1600
1800
1900 2000 2100
Sample Number
2200
2300
2400
D128
JMODE0, fCLK = 3200 MHz, DC input
Figure 63. Background Calibration Core Transition
(DC Signal Zoomed)(1)
These curves are taken at a clock frequency higher than the rated maximum clock frequency but are representative of results at the
rated maximum clock frequency.
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7 Detailed Description
7.1 Overview
ADC12DJ2700 device is an RF-sampling, giga-sample, analog-to-digital converter (ADC) that can directly sample
input frequencies from DC to above 10 GHz. In dual-channel mode, the ADC12DJ2700 can sample up to 2700
GSPS and up to 5400 GSPS in single-channel mode. Programmable tradeoffs in channel count (dual-channel
mode) and Nyquist bandwidth (single-channel mode) allow development of flexible hardware that meets the
needs of both high channel count or wide instantaneous signal bandwidth applications. Full-power input
bandwidth (–3 dB) of 8.0 GHz, with usable frequencies exceeding the –3-dB point in both dual- and singlechannel modes, allows direct RF sampling of L-band, S-band, C-band, and X-band for frequency agile systems.
ADC12DJ2700 uses a high-speed JESD204B output interface with up to 16 serialized lanes and subclass-1
compliance for deterministic latency and multi-device synchronization. The serial output lanes support up to 12.8
Gbps and can be configured to trade-off bit rate and number of lanes.
A number of synchronization features, including noiseless aperture delay (tAD) adjustment and SYSREF
windowing, simplify system design for multi-channel systems. Aperture delay adjustment can be used to simplify
SYSREF capture, to align the sampling instance between multiple ADCs or to sample an ideal location of a frontend track and hold (T&H) amplifier output. SYSREF windowing offers a simplistic way to measure invalid timing
regions of SYSREF relative to the device clock and then choose an optimal sampling location. Dual-edge
sampling (DES) is implemented in single-channel mode to reduce the maximum clock rate applied to the ADC to
support a wide range of clock sources and relax setup and hold timing for SYSREF capture.
Optional digital down converters (DDCs) are available in dual-channel mode to allow a reduction in interface rate
(decimation) and digital mixing of the signal to baseband. The DDC block supports data decimation of 4x, 8x or
16x and alias-free complex output bandwidths of 80% of the effective output data rate.
ADC12DJ2700 provides foreground and background calibration options for gain, offset and static linearity errors.
Foreground calibration is run at system startup or at specified times during which the ADC is offline and not
sending data to the logic device. Background calibration allows the ADC to run continually while the cores are
calibrated in the background so that the system does not experience downtime. The calibration routine is also
used to match the gain and offset between sub-ADC cores to minimize spurious artifacts from time interleaving.
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7.2 Functional Block Diagram
NCOA0
SCLK
SDI
SDO
SCS\
NCOA1 NCOB0
NCOB1
CALTRG
PD
SPI Registers and
Device Control
DDC Bypass / Single-Channel Mode
TMSTP+
INA+
DDCA
NCO
Bank A
TMSTP±
Input
MUX
ADC A
DA0+
DA0±
JESD20
4B
Link A
N
Mixer
INA±
DA7+
DA7±
Filter
JMODE
DDC Bypass / Single-Channel Mode
Overrange
SYNCSE\
INB+
INB±
Input
MUX
DB7+
DB7±
Filter
DIGBIND
JMODE
Clock Distribution
and Synchronization
CLK±
SYSREF±
JESD20
4B
Link B
N
Mixer
CLK+
DB0+
DB0±
ADC B
Aperture
Delay Adjust
SYSREF+
DDC B
NCO
Bank B
Status
Indicators
SYSREF
Windowing
TDIODE+
ORA0
ORA1
ORB0
ORB1
CALSTAT
TDIODE±
7.3 Feature Description
7.3.1 Device Comparison
The devices listed in Table 1 are part of a pin-to-pin compatible, high-speed, wide-bandwidth ADC family. The
family is offered to provide a scalable family of devices for varying resolution, sampling rate and signal
bandwidth.
Table 1. Device Family Comparison
MAXIMUM
SAMPLING RATE
RESOLUTION
DUAL CHANNEL
DECIMATION
SINGLE CHANNEL
DECIMATION
INTERFACE
(MAX LINERATE)
ADC12DJ5200RF
Single 10.4 GSPS
Dual 5.2 GSPS
12-bit
Complex: 4x, 8x
Complex: 4x, 8x
JESD204B /
JESD204C
(17.16 Gbps)
ADC12DJ3200
Single 6.4 GSPS
Dual 3.2 GSPS
12-bit
Real: 2x
Complex: 4x, 8x, 16x
None
JESD204B
(12.8 Gbps)
ADC08DJ3200
Single 6.4 GSPS
Dual 3.2 GSPS
8-bit
None
None
JESD204B
(12.8 Gbps)
ADC12DJ2700
Single 5.4 GSPS
Dual 2.7 GSPS
12-bit
Real: 2x
Complex: 4x, 8x, 16x
None
JESD204B
(12.8 Gbps)
PART NUMBER
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7.3.2 Analog Inputs
The analog inputs of the ADC12DJ2700 have internal buffers to enable high input bandwidth and to isolate
sampling capacitor glitch noise from the input circuit. Analog inputs must be driven differentially because
operation with a single-ended signal results in degraded performance. Both AC-coupling and DC-coupling of the
analog inputs is supported. The analog inputs are designed for an input common-mode voltage (VCMI) of 0 V,
which is terminated internally through single-ended, 50-Ω resistors to ground (GND) on each input pin. DCcoupled input signals must have a common-mode voltage that meets the device input common-mode
requirements specified as VCMI in the Recommended Operating Conditions table. The 0-V input common-mode
voltage simplifies the interface to split-supply, fully-differential amplifiers and to a variety of transformers and
baluns. The ADC12DJ2700 includes internal analog input protection to protect the ADC inputs during overranged
input conditions; see the Analog Input Protection section. Figure 64 provides a simplified analog input model.
AGND
Analog Input
Protection
Diodes
50
INA+, INB+
ADC
INA±, INB±
50
Input Buffer
Figure 64. ADC12DJ2700 Analog Input Internal Termination and Protection Diagram
There is minimal degradation in analog input bandwidth when using single-channel mode versus dual-channel
mode. In single-channel mode, INA± is strongly recommended to be used as the input to the ADC because ADC
performance is optimized for INA±. However, either analog input (INA+ and INA– or INB+ and INB–) can be
used. Using INB± results in degraded performance unless custom trim routines are used to optimize performance
for INB± in each device. The desired input can be chosen using SINGLE_INPUT in the input mux control
register.
NOTE
INA± is strongly recommended to be used as the input to the ADC in single-channel mode
for optimized performance.
7.3.2.1 Analog Input Protection
The analog inputs are protected against overdrive conditions by internal clamping diodes that are capable of
sourcing or sinking input currents during overrange conditions, see the voltage and current limits in the Absolute
Maximum Ratings table. The overrange protection is also defined for a peak RF input power in the Absolute
Maximum Ratings table, which is frequency independent. Operation above the maximum conditions listed in the
Recommended Operating Conditions table results in an increase in failure-in-time (FIT) rate, so the system must
correct the overdrive condition as quickly as possible. Figure 64 shows the analog input protection diodes.
7.3.2.2 Full-Scale Voltage (VFS) Adjustment
Input full-scale voltage (VFS) adjustment is available, in fine increments, for each analog input through the
FS_RANGE_A register setting (see the INA full-scale range adjust register) and FS_RANGE_B register setting
(see the INB full-scale range adjust register) for INA± and INB±, respectively. The available adjustment range is
specified in the Electrical Characteristics: DC Specifications table. Larger full-scale voltages improve SNR and
noise floor (in dBFS/Hz) performance, but may degrade harmonic distortion. The full-scale voltage adjustment is
useful for matching the full-scale range of multiple ADCs when developing a multi-converter system or for
external interleaving of multiple ADC12DJ2700s to achieve higher sampling rates.
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7.3.2.3 Analog Input Offset Adjust
The input offset voltage for each input can be adjusted through the SPI register. The OADJ_A_INx registers
(registers 0x08A and 0x08D) are used to adjust ADC core A's offset voltage when sampling analog input x
(where x is A for INA± or B for INB±). OADJ_B_INx is used to adjust ADC core B's offset voltage when sampling
input x. These registers apply to both dual channel mode and single channel mode. To adjust the offset voltage
in dual channel mode simply adjust the offset to the ADC core sampling the desired input. In single channel
mode, both ADC core A's and ADC core B's offset must be adjusted together. The difference in the two core's
offsets in single channel mode results in a spur at fS/2 that is independent of the input. These registers can be
used to compensate the fS/2 spur in single channel mode. See the Calibration Modes and Trimming section for
more information.
7.3.3 ADC Core
The ADC12DJ2700 consists of a total of six ADC cores. The cores are interleaved for higher sampling rates and
swapped on-the-fly for calibration as required by the operating mode. This section highlights the theory and key
features of the ADC cores.
7.3.3.1 ADC Theory of Operation
The differential voltages at the analog inputs are captured by the rising edge of CLK± in dual-channel mode or by
the rising and falling edges of CLK± in single-channel mode. After capturing the input signal, the ADC converts
the analog voltage to a digital value by comparing the voltage to the internal reference voltage. If the voltage on
INA– or INB– is higher than the voltage on INA+ or INB+, respectively, then the digital output is a negative 2's
complement value. If the voltage on INA+ or INB+ is higher than the voltage on INA– or INB–, respectively, then
the digital output is a positive 2's complement value. Equation 1 can calculate the differential voltage at the input
pins from the digital output.
Code
VIN
V FS
2N
where
•
•
•
Code is the signed decimation output code (for example, –2048 to +2047)
N is the ADC resolution
and VFS is the full-scale input voltage of the ADC as specified in the Recommended Operating Conditions
table, including any adjustment performed by programming FS_RANGE_A or FS_RANGE_B
(1)
7.3.3.2 ADC Core Calibration
ADC core calibration is required to optimize the analog performance of the ADC cores. Calibration must be
repeated when operating conditions change significantly, namely temperature, in order to maintain optimal
performance. The ADC12DJ2700 has a built-in calibration routine that can be run as a foreground operation or a
background operation. Foreground operation requires ADC downtime, where the ADC is no longer sampling the
input signal, to complete the process. Background calibration can be used to overcome this limitation and allow
constant operation of the ADC. See the Calibration Modes and Trimming section for detailed information on each
mode.
7.3.3.3 Analog Reference Voltage
The reference voltage for the ADC12DJ2700 is derived from an internal band-gap reference. A buffered version
of the reference voltage is available at the BG pin for user convenience. This output has an output-current
capability of ±100 µA. The BG output must be buffered if more current is required. No provision exists for the use
of an external reference voltage, but the full-scale input voltage can be adjusted through the full-scale-range
register settings. In unique cases, the VA11 supply voltage can act as the reference voltage by setting
BG_BYPASS (see the internal reference bypass register).
38
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7.3.3.4 ADC Overrange Detection
To ensure that system gain management has the quickest possible response time, a low-latency configurable
overrange function is included. The overrange function works by monitoring the converted 12-bit samples at the
ADC to quickly detect if the ADC is near saturation or already in an overrange condition. The absolute value of
the upper 8 bits of the ADC data are checked against two programmable thresholds, OVR_T0 and OVR_T1.
These thresholds apply to both channel A and channel B in dual-channel mode. Table 2 lists how an ADC
sample is converted to an absolute value for a comparison of the thresholds.
Table 2. Conversion of ADC Sample for Overrange Comparison
ADC SAMPLE
(Offset Binary)
ADC SAMPLE
(2's Complement)
ABSOLUTE VALUE
UPPER 8 BITS USED FOR
COMPARISON
1111 1111 1111 (4095)
0111 1111 1111 (+2047)
111 1111 1111 (2047)
1111 1111 (255)
1111 1111 0000 (4080)
0111 1111 0000 (+2032)
111 1111 0000 (2032)
1111 1110 (254)
1000 0000 0000 (2048)
0000 0000 0000 (0)
000 0000 0000 (0)
0000 0000 (0)
0000 0001 0000 (16)
1000 0001 0000 (–2032)
111 1111 0000 (2032)
1111 1110 (254)
0000 0000 0000 (0)
1000 0000 0000 (–2048)
111 1111 1111 (2047)
1111 1111 (255)
If the upper 8 bits of the absolute value equal or exceed the OVR_T0 or OVR_T1 thresholds during the
monitoring period, then the overrange bit associated with the threshold is set to 1, otherwise the overrange bit is
0. In dual-channel mode, the overrange status can be monitored on the ORA0 and ORA1 pins for channel A and
the ORB0 and ORB1 pins for channel B, where ORx0 corresponds to the OVR_T0 threshold and ORx1
corresponds to the OVR_T1 threshold. In single-channel mode, the overrange status for the OVR_T0 threshold
is determined by monitoring both the ORA0 and ORB0 outputs and the OVR_T1 threshold is determined by
monitoring both ORA1 and ORB1 outputs. In single-channel mode, the two outputs for each threshold must be
OR'd together to determine whether an overrange condition occurred. OVR_N can be used to set the output
pulse duration from the last overrange event. Table 3 lists the overrange pulse lengths for the various OVR_N
settings (see the overrange configuration register). In decimation modes (only in the JMODEs where CS = 1 in
Table 19), the overrange status is also embedded into the output data samples. For complex decimation modes,
the OVR_T0 threshold status is embedded as the LSB along with the upper 15 bits of every complex I sample
and the OVR_T1 threshold status is embedded as the LSB along with the upper 15 bits of every complex Q
sample. For real decimation modes, the OVR_T0 threshold status is embedded as the LSB of every evennumbered sample and the OVR_T1 threshold status is embedded as the LSB of every odd-numbered sample.
Table 4 lists the outputs, related data samples, threshold settings, and the monitoring period equation. The
embedded overrange bit goes high if the associated channel exceeds the associated overrange threshold within
the monitoring period set by OVR_N. Use Table 4 to calculate the monitoring period.
Table 3. Overrange Monitoring Period for the ORA0, ORA1, ORB0, and ORB1 Outputs
OVR_N
OVERRANGE PULSE LENGTH SINCE LAST OVERRANGE
EVENT (DEVCLK Cycles)
0
8
1
16
2
32
3
64
4
128
5
256
6
512
7
1024
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Table 4. Threshold and Monitoring Period for Embedded Overrange Indicators in Dual-Channel
Decimation Modes
OVERRANGE
INDICATOR
ORA0
ORA1
ORB0
ORB1
(1)
ASSOCIATED
THRESHOLD
OVR_T0
OVR_T1
OVR_T0
OVR_T1
DECIMATION TYPE
OVERRANGE STATUS
EMBEDDED IN
MONITORING PERIOD
(ADC Samples)
Real decimation (JMODE 9)
Channel A evennumbered samples
2OVR_N+1 (1)
Complex down-conversion (JMODE
10-16, except JMODE 12)
Channel A in-phase (I)
samples
2OVR_N (1)
Real decimation (JMODE 9)
Channel A oddnumbered samples
2OVR_N+1 (1)
Complex down-conversion (JMODE
10-16, except JMODE 12)
Channel A quadrature
(Q) samples
2OVR_N (1)
Real decimation (JMODE 9)
Channel B evennumbered samples
2OVR_N+1 (1)
Complex down-conversion (JMODE
10-16, except JMODE 12)
Channel B in-phase (I)
samples
2OVR_N (1)
Real decimation (JMODE 9)
Channel B oddnumbered samples
2OVR_N+1 (1)
Complex down-conversion (JMODE
10-16, except JMODE 12)
Channel B quadrature
(Q) samples
2OVR_N (1)
OVR_N is the monitoring period register setting.
Typically, the OVR_T0 threshold can be set near the full-scale value (228 for example). When the threshold is
triggered, a typical system can turn down the system gain to avoid clipping. The OVR_T1 threshold can be set
much lower. For example, the OVR_T1 threshold can be set to 64 (peak input voltage of −12 dBFS). If the input
signal is strong, the OVR_T1 threshold is tripped occasionally. If the input is quite weak, the threshold is never
tripped. The downstream logic device monitors the OVR_T1 bit. If OVR_T1 stays low for an extended period of
time, then the system gain can be increased until the threshold is occasionally tripped (meaning the peak level of
the signal is above −12 dBFS).
7.3.3.5 Code Error Rate (CER)
ADC cores can generate bit errors within a sample, often called code errors (CER) or referred to as sparkle
codes, resulting from metastability caused by non-ideal comparator limitations. The ADC12DJ2700 uses a
unique ADC architecture that inherently allows significant code error rate improvements from traditional pipelined
flash or successive approximation register (SAR) ADCs. The code error rate of the ADC12DJ2700 is multiple
orders of magnitude better than what can be achieved in alternative architectures at equivalent sampling rates
providing significant signal reliability improvements.
7.3.4 Temperature Monitoring Diode
A built-in thermal monitoring diode is made available on the TDIODE+ and TDIODE– pins. This diode facilitates
temperature monitoring and characterization of the device in higher ambient temperature environments. Although
the on-chip diode is not highly characterized, the diode can be used effectively by performing a baseline
measurement (offset) at a known ambient or board temperature and creating a linear equation with the diode
voltage slope provided in the Electrical Characteristics: DC Specifications table. Perform offset measurement
with the device unpowered or with the PD pin asserted to minimize device self-heating. Only assert the PD pin
long enough to take the offset measurement. Recommended monitoring devices include the LM95233 device
and similar remote-diode temperature monitoring products from Texas Instruments.
7.3.5 Timestamp
The TMSTP+ and TMSTP– differential input can be used as a time-stamp input to mark a specific sample based
on the timing of an external trigger event relative to the sampled signal. TIMESTAMP_EN (see the LSB control
bit output register) must be set in order to use the timestamp feature and output the timestamp data. When
enabled, the LSB of the 12-bit ADC digital output reports the status of the TMSTP± input. In effect, the 12-bit
output sample consists of the upper 11-bits of the 12-bit converter and the LSB of the 12-bit output sample is the
output of a parallel 1-bit converter (TMSTP±) with the same latency as the ADC core. In the 8-bit operating
40
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modes, the LSB of the 8-bit output sample is used to output the timestamp status. The trigger must be applied to
the differential TMSTP+ and TMSTP– inputs. The trigger can be asynchronous to the ADC sampling clock and is
sampled at approximately the same time as the analog input. Timestamp cannot be used when a JMODE with
decimation is selected and instead SYSREF must be used to achieve synchronization through the JESD204B
subclass-1 method for achieving deterministic latency.
7.3.6 Clocking
The clocking subsystem of the ADC12DJ2700 has two input signals, device clock (CLK+, CLK–) and SYSREF
(SYSREF+, SYSREF–). Within the clocking subsystem there is a noiseless aperture delay adjustment (tAD
adjust), a clock duty cycle corrector, and a SYSREF capture block. Figure 65 describes the clocking subsystem.
Duty Cycle
Correction
tAD Adjust
Clock Distribution
and Synchronization
(ADC cores, digital,
JESD204B, etc.)
CLK+
E
TA
D
_F
IN
SE
O
AR
TA
D
_C
TA
D
_I
N
V
CLK-
SYSREF Capture
SYSREF+
SYSREF Windowing
SYSREF-
SYSREF_POS
SYSREF_SEL
Automatic
SYSREF
Calibration
SRC_EN
Figure 65. ADC12DJ2700 Clocking Subsystem
The device clock is used as the sampling clock for the ADC core as well as the clocking for the digital processing
and serializer outputs. Use a low-noise (low jitter) device clock to maintain high signal-to-noise ratio (SNR) within
the ADC. In dual-channel mode, the analog input signal for each input is sampled on the rising edge of the
device clock. In single-channel mode, both the rising and falling edges of the device clock are used to capture
the analog signal to reduce the maximum clock rate required by the ADC. A noiseless aperture delay adjustment
(tAD adjust) allows the user to shift the sampling instance of the ADC in fine steps in order to synchronize multiple
ADC12DJ2700s or to fine-tune system latency. Duty cycle correction is implemented in the ADC12DJ2700 to
ease the requirements on the external device clock while maintaining high performance. Table 5 summarizes the
device clock interface in dual-channel mode and single-channel mode.
Table 5. Device Clock vs Mode of Operation
MODE OF OPERATION
SAMPLING RATE VS fCLK
Dual-channel mode
1 × fCLK
SAMPLING INSTANT
Rising edge
Single-channel mode
2 × fCLK
Rising and falling edge
SYSREF is a system timing reference used for JESD204B subclass-1 implementations of deterministic latency.
SYSREF is used to achieve deterministic latency and for multi-device synchronization. SYSREF must be
captured by the correct device clock edge in order to achieve repeatable latency and synchronization. The
ADC12DJ2700 includes SYSREF windowing and automatic SYSREF calibration to ease the requirements on the
external clocking circuits and to simplify the synchronization process. SYSREF can be implemented as a single
pulse or as a periodic clock. In periodic implementations, SYSREF must be equal to, or an integer division of, the
local multiframe clock frequency. Equation 2 is used to calculate valid SYSREF frequencies.
f SYSREF
R u f CLK
10 u F u K u n
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where
•
•
•
•
R and F are set by the JMODE setting (see Table 19)
fCLK is the device clock frequency (CLK±)
K is the programmed multiframe length (see Table 19 for valid K settings)
and n is any positive integer
(2)
7.3.6.1 Noiseless Aperture Delay Adjustment (tAD Adjust)
The ADC12DJ2700 contains a delay adjustment on the device clock (sampling clock) input path, called tAD
adjust, that can be used to shift the sampling instance within the device in order to align sampling instances
among multiple devices or for external interleaving of multiple ADC12DJ2700s. Further, tAD adjust can be used
for automatic SYSREF calibration to simplify synchronization; see the Automatic SYSREF Calibration section.
Aperture delay adjustment is implemented in a way that adds no additional noise to the clock path, however a
slight degradation in aperture jitter (tAJ) is possible at large values of TAD_COARSE because of internal clock
path attenuation. The degradation in aperture jitter can result in minor SNR degradations at high input
frequencies (see tAJ in the Switching Characteristics table). This feature is programmed using TAD_INV,
TAD_COARSE, and TAD_FINE in the DEVCLK timing adjust ramp control register. Setting TAD_INV inverts the
input clock resulting in a delay equal to half the clock period. Table 6 summarizes the step sizes and ranges of
the TAD_COARSE and TAD_FINE variable analog delays. All three delay options are independent and can be
used in conjunction. All clocks within the device are shifted by the programmed tAD adjust amount, which results
in a shift of the timing of the JESD204B serialized outputs and affects the capture of SYSREF.
Table 6. tAD Adjust Adjustment Ranges
ADJUSTMENT PARAMETER
ADJUSTMENT STEP
DELAY SETTINGS
MAXIMUM DELAY
TAD_INV
1 / (fCLK × 2)
1
1 / (fCLK × 2)
TAD_COARSE
See tTAD(STEP) in the Switching
Characteristics table
256
See tTAD(MAX) in the Switching
Characteristics table
TAD_FINE
See tTAD(STEP) in the Switching
Characteristics table
256
See tTAD(MAX) in the Switching
Characteristics table
In order to maintain timing alignment between converters, stable and matched power-supply voltages and device
temperatures must be provided.
Aperture delay adjustment can be changed on-the-fly during normal operation but may result in brief upsets to
the JESD204B data link. Use TAD_RAMP to reduce the probability of the JESD204B link losing synchronization;
see the Aperture Delay Ramp Control (TAD_RAMP) section.
7.3.6.2 Aperture Delay Ramp Control (TAD_RAMP)
The ADC12DJ2700 contains a function to gradually adjust the tAD adjust setting towards the newly written
TAD_COARSE value. This functionality allows the tAD adjust setting to be adjusted with minimal internal clock
circuitry glitches. The TAD_RAMP_RATE parameter allows either a slower (one TAD_COARSE LSB per 256
tCLK cycles) or faster ramp (four TAD_COARSE LSBs per 256 tCLK cycles) to be selected. The TAD_RAMP_EN
parameter enables the ramp feature and any subsequent writes to TAD_COARSE initiate a new cramp.
7.3.6.3 SYSREF Capture for Multi-Device Synchronization and Deterministic Latency
The clocking subsystem is largely responsible for achieving multi-device synchronization and deterministic
latency. The ADC12DJ2700 uses the JESD204B subclass-1 method to achieve deterministic latency and
synchronization. Subclass 1 requires that the SYSREF signal be captured by a deterministic device clock (CLK±)
edge at each system power-on and at each device in the system. This requirement imposes setup and hold
constraints on SYSREF relative to CLK±, which can be difficult to meet at giga-sample clock rates over all
system operating conditions. The ADC12DJ2700 includes a number of features to simplify this synchronization
process and to relax system timing constraints:
• The ADC12DJ2700 uses dual-edge sampling (DES) in single-channel mode to reduce the CLK± input
frequency by half and double the timing window for SYSREF (see Table 5)
• A SYSREF position detector (relative to CLK±) and selectable SYSREF sampling position aid the user in
meeting setup and hold times over all conditions; see the SYSREF Position Detector and Sampling Position
Selection (SYSREF Windowing) section
• Easy-to-use automatic SYSREF calibration uses the aperture timing adjust block (tAD adjust) to shift the ADC
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sampling instance based on the phase of SYSREF (rather than adjusting SYSREF based on the phase of the
ADC sampling instance); see the Automatic SYSREF Calibration section
7.3.6.3.1 SYSREF Position Detector and Sampling Position Selection (SYSREF Windowing)
The SYSREF windowing block is used to first detect the position of SYSREF relative to the CLK± rising edge and
then to select a desired SYSREF sampling instance, which is a delay version of CLK±, to maximize setup and
hold timing margins. In many cases a single SYSREF sampling position (SYSREF_SEL) is sufficient to meet
timing for all systems (device-to-device variation) and conditions (temperature and voltage variations). However,
this feature can also be used by the system to expand the timing window by tracking the movement of SYSREF
as operating conditions change or to remove system-to-system variation at production test by finding a unique
optimal value at nominal conditions for each system.
This section describes proper usage of the SYSREF windowing block. First, apply the device clock and SYSREF
to the device. The location of SYSREF relative to the device clock cycle is determined and stored in the
SYSREF_POS bits of the SYSREF capture position register. ADC12DJ2700 must see at least 3 rising edges of
SYSREF before the SYSREF_POS output is valid. Each bit of SYSREF_POS represents a potential SYSREF
sampling position. If a bit in SYSREF_POS is set to 1, then the corresponding SYSREF sampling position has a
potential setup or hold violation. Upon determining the valid SYSREF sampling positions (the positions of
SYSREF_POS that are set to 0) the desired sampling position can be chosen by setting SYSREF_SEL in the
clock control register 0 to the value corresponding to that SYSREF_POS position. In general, the middle
sampling position between two setup and hold instances is chosen. Ideally, SYSREF_POS and SYSREF_SEL
are performed at the nominal operating conditions of the system (temperature and supply voltage) to provide
maximum margin for operating condition variations. This process can be performed at final test and the optimal
SYSREF_SEL setting can be stored for use at every system power up. Further, SYSREF_POS can be used to
characterize the skew between CLK± and SYSREF± over operating conditions for a system by sweeping the
system temperature and supply voltages. For systems that have large variations in CLK± to SYSREF± skew, this
characterization can be used to track the optimal SYSREF sampling position as system operating conditions
change. In general, a single value can be found that meets timing over all conditions for well-matched systems,
such as those where CLK± and SYSREF± come from a single clocking device.
NOTE
SYSREF_SEL must be set to 0 when using automatic SYSREF calibration; see the
Automatic SYSREF Calibration section.
The step size between each SYSREF_POS sampling position can be adjusted using SYSREF_ZOOM. When
SYSREF_ZOOM is set to 0, the delay steps are coarser. When SYSREF_ZOOM is set to 1, the delay steps are
finer. See the Switching Characteristics table for delay step sizes when SYSREF_ZOOM is enabled and
disabled. In general, SYSREF_ZOOM is recommended to always be used (SYSREF_ZOOM = 1) unless a
transition region (defined by 1's in SYSREF_POS) is not observed, which can be the case for low clock rates.
Bits 0 and 23 of SYSREF_POS are always be set to 1 because there is insufficient information to determine if
these settings are close to a timing violation, although the actual valid window can extend beyond these sampling
positions. The value programmed into SYSREF_SEL is the decimal number representing the desired bit location
in SYSREF_POS. Table 7 lists some example SYSREF_POS readings and the optimal SYSREF_SEL settings.
Although 24 sampling positions are provided by the SYSREF_POS status register, SYSREF_SEL only allows
selection of the first 16 sampling positions, corresponding to SYSREF_POS bits 0 to 15. The additional
SYSREF_POS status bits are intended only to provide additional knowledge of the SYSREF valid window. In
general, lower values of SYSREF_SEL are selected because of delay variation over supply voltage, however in
the fourth example a value of 15 provides additional margin and can be selected instead.
Table 7. Examples of SYSREF_POS Readings and SYSREF_SEL Selections
SYSREF_POS[23:0]
(1)
OPTIMAL SYSREF_SEL
SETTING
0x02E[7:0]
(Largest Delay)
0x02D[7:0] (1)
0x02C[7:0] (1)
(Smallest Delay)
b10000000
b01100000
b00011001
b10011000
b00000000
b00110001
12
b10000000
b01100000
b00000001
6 or 7
8 or 9
Red coloration indicates the bits that are selected, as given in the last column of this table.
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Table 7. Examples of SYSREF_POS Readings and SYSREF_SEL Selections (continued)
SYSREF_POS[23:0]
OPTIMAL SYSREF_SEL
SETTING
0x02E[7:0]
(Largest Delay)
0x02D[7:0] (1)
0x02C[7:0] (1)
(Smallest Delay)
b10000000
b00000011
b00000001
4 or 15
b10001100
b01100011
b00011001
6
7.3.6.3.2 Automatic SYSREF Calibration
The ADC12DJ2700 has an automatic SYSREF calibration feature to alleviate the often challenging setup and
hold times associated with capturing SYSREF for giga-sample data converters. Automatic SYSREF calibration
uses the tAD adjust feature to shift the device clock to maximize the SYSREF setup and hold times or to align the
sampling instance based on the SYSREF rising edge.
The ADC12DJ2700 must have a proper device clock applied and be programmed for normal operation before
starting the automatic SYSREF calibration. When ready to initiate automatic SYSREF calibration, a continuous
SYSREF signal must be applied. SYSREF must be a continuous (periodic) signal when using the automatic
SYSREF calibration. Start the calibration process by setting SRC_EN high in the SYSREF calibration enable
register after configuring the automatic SYSREF calibration using the SRC_CFG register. Upon setting SRC_EN
high, the ADC12DJ2700 searches for the optimal tAD adjust setting until the device clock falling edge is internally
aligned to the SYSREF rising edge. TAD_DONE in the SYSREF calibration status register can be monitored to
ensure that the SYSREF calibration has finished. By aligning the device clock falling edge with the SYSREF
rising edge, automatic SYSREF calibration maximizes the internal SYSREF setup and hold times relative to the
device clock and also sets the sampling instant based on the SYSREF rising edge. After the automatic SYSREF
calibration finishes, the rest of the startup procedure can be performed to finish bringing up the system.
For multi-device synchronization, the SYSREF rising edge timing must be matched at all devices and therefore
trace lengths must be matched from a common SYSREF source to each ADC12DJ2700. Any skew between the
SYSREF rising edge at each device results in additional error in the sampling instance between devices,
however repeatable deterministic latency from system startup to startup through each device must still be
achieved. No other design requirements are needed in order to achieve multi-device synchronization as long as
a proper elastic buffer release point is chosen in the JESD2048 receiver.
Figure 66 provides a timing diagram of the SYSREF calibration procedure. The optimized setup and hold times
are shown as tSU(OPT) and tH(OPT), respectively. Device clock and SYSREF are referred to as internal in this
diagram because the phase of the internal signals are aligned within the device and not to the external (applied)
phase of the device clock or SYSREF.
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Sampled Input Signal
Internal Unadjusted
Device Clock
Internal Calibrated
Device Clock
tTAD(SRC)
Internal SYSREF
tCAL(SRC)
SRC_EN
(SPI register bit)
tH(OPT)
tSU(OPT)
Before calibration, device clock falling edge does
not align with SYSREF rising edge
Calibration
enabled
TAD_DONE
(SPI register bit)
After calibration, device clock falling edge
aligns with SYSREF rising edge
Calibration
finished
Figure 66. SYSREF Calibration Timing Diagram
When finished, the tAD adjust setting found by the automatic SYSREF calibration can be read from SRC_TAD in
the SYSREF calibration status register. After calibration, the system continues to use the calibrated tAD adjust
setting for operation until the system is powered down. However, if desired, the user can then disable the
SYSREF calibration and fine-tune the tAD adjust setting according to the systems needs. Alternatively, the use of
the automatic SYSREF calibration can be done at product test (or periodic recalibration) of the optimal tAD adjust
setting for each system. This value can be stored and written to the TAD register (TAD_INV, TAD_COARSE, and
TAD_FINE) upon system startup.
Do not run the SYSREF calibration when the ADC calibration (foreground or background) is running. If
background calibration is the desired use case, disable the background calibration when the SYSREF calibration
is used, then reenable the background calibration after TAD_DONE goes high. SYSREF_SEL in the clock control
register 0 must be set to 0 when using SYSREF calibration.
SYSREF calibration searches the TAD_COARSE delays using both noninverted (TAD_INV = 0) and inverted
clock polarity (TAD_INV = 1) to minimize the required TAD_COARSE setting in order to minimize loss on the
clock path to reduce aperture jitter (tAJ).
7.3.7 Digital Down Converters (Dual-Channel Mode Only)
After converting the analog voltage to a digital value, the digitized sample can either be sent directly to the
JESD204B interface block (DDC bypass) or sent to the digital down conversion (DDC) block for frequency
conversion and decimation (in dual-channel mode only). Frequency conversion and decimation allow a specific
frequency band to be selected and output in the digital data stream while reducing the effective data rate and
interface speed or width. The DDC is designed such that the digital processing does not degrade the noise
spectral density (NSD) performance of the ADC. Figure 67 illustrates the digital down converter for channel A of
the ADC12DJ2700. Channel B has the same structure with the input data selected by DIG_BIND_B and the
NCO selection mux controlled by pins NCOB[1:0] or through CSELB[1:0].
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NCO Bank A
NCOA[1:0] or
CSELA[1:0]
Complex
15-bit
at Fs/N
MUX
Real
15-bit
at Fs/2
2
Low Pass
High Pass
JESD204B
JMODE
JMODE
(DDC Bypass)
Spectral
Inversion
2
ADC
Channel B
2
Decimate-by-N
(based on JMODE)
MUX
DIG_BIND_A
Complex
Mixer
MUX
ADC
Channel A
MUX
N
Real
12-bit
at Fs
MUX
MUX
D2_HIGH_PASS
INVERT_SPECTRUM
Figure 67. Channel A Digital Down Conversion Block (Dual-Channel Mode Only)
7.3.7.1 Numerically-Controlled Oscillator and Complex Mixer
The DDC contains a complex numerically-controlled oscillator (NCO) and a complex mixer. Equation 3 shows the
complex exponential sequence generated by the oscillator.
x[n] = ejωn
(3)
The frequency (ω) is specified by a 32-bit register setting. The complex exponential sequence is multiplied by the
real input from the ADC to mix the desired carrier to a frequency equal to fIN + fNCO, where fIN is the analog input
frequency after aliasing (in undersampling systems) and fNCO is the programmed NCO frequency.
7.3.7.1.1 NCO Fast Frequency Hopping (FFH)
Fast frequency hopping (FFH) is made possible by each DDC having four independent NCOs that can be
controlled by the NCOA0 and NCOA1 pins for DDC A and the NCOB0 and NCOB1 pins for DDC B. Each NCO
has independent frequency settings (see the Basic NCO Frequency Setting Mode section) and initial phase
settings (see the NCO Phase Offset Setting section) that can be set independently. Further, all NCOs have
independent phase accumulators that continue to run when the specific NCO is not selected, allowing the NCOs
to maintain their phase between selection so that downstream processing does not need to perform carrier
recovery after each hop, for instance.
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NCO hopping occurs when the NCO GPIO pins change state. The pins are controlled asynchronously and
therefore synchronous switching is not possible. Associated latencies are demonstrated in Figure 68, where tTX
and tADC are provided in the Switching Characteristics table. All latencies in Table 8 are approximations only.
DDC Block
NCO Bank A
tGPIO-MIXER
tMIXER-TX
NCOx[1:0]
MUX
Dx0±
Dx1±
INx+
N
ADC
JESD204B
Dx2±
INx±
Complex
Mixer
Decimate-by-N
(based on JMODE)
Dx7±
tADC-MIXER
Figure 68. NCO Fast Frequency Hopping Latency Diagram
Table 8. NCO Fast Frequency Hopping Latency Definitions
LATENCY PARAMETER
VALUE OR CALCULATION
UNITS
tGPIO-MIXER
~36 to ~40
tCLK cycles
tADC-MIXER
~36
tCLK cycles
tMIXER-TX
(tTX + tADC) – tADC-MIXER
tCLK cycles
7.3.7.1.2 NCO Selection
Within each channel DDC, four different frequency and phase settings are available for use. Each of the four
settings use a different phase accumulator within the NCO. Because all four phase accumulators are
independent and continuously running, rapid switching between different NCO frequencies is possible allowing
for phase coherent frequency hopping.
The specific frequency-phase pair used for each channel is selected through the NCOA[1:0] or NCOB[1:0] input
pins when CMODE is set to 1. Alternatively, the selected NCO can be chosen through SPI by CSELA for DDC A
and CSELB for DDC B by setting CMODE to 0 (default). The logic table for NCO selection is provided in Table 9
for both the GPIO and SPI selection options.
Table 9. Logic Table for NCO Selection Using GPIO or SPI
NCO SELECTION
CMODE
NCOx1
NCOx0
CSELx[1]
CSELx[0]
NCO 0 using GPIO
1
0
0
X
X
NCO 1 using GPIO
1
0
1
X
X
NCO 2 using GPIO
1
1
0
X
X
NCO 3 using GPIO
1
1
1
X
X
NCO 0 using SPI
0
X
X
0
0
NCO 1 using SPI
0
X
X
0
1
NCO 2 using SPI
0
X
X
1
0
NCO 3 using SPI
0
X
X
1
1
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The frequency for each phase accumulator is programmed independently through the FREQAx, FREQBx (x = 0
to 3) and, optionally, NCO_RDIV register settings. The phase offset for each accumulator is programmed
independently through the PHASEAx and PHASEBx (x = 0 to 3) register settings.
7.3.7.1.3 Basic NCO Frequency Setting Mode
In basic NCO frequency-setting mode (NCO_RDIV = 0x0000), the NCO frequency setting is set by the 32-bit
register value, FREQAx and FREQBx (x = 0 to 3). The NCO frequency for DDC A can be calculated using
Equation 4, where FREQAx can be replaced by FREQBx to calculate the NCO frequency for DDC B.
ƒ(NCO) = FREQAx × 2–32 × ƒ(DEVCLK) (x = 0 – 3)
(4)
NOTE
Changing the FREQAx and FREQBx register settings during operation results in a nondeterministic NCO phase. If deterministic phase is required, the NCOs must be
resynchronized; see the NCO Phase Synchronization section.
7.3.7.1.4 Rational NCO Frequency Setting Mode
In basic NCO frequency mode, the frequency step size is very small and many frequencies can be synthesized,
but sometimes an application requires very specific frequencies that fall between two frequency steps. For
example with ƒS equal to 2457.6 MHz and a desired ƒ(NCO) equal to 5.02 MHz, the value for FREQAx is
8773085.867. Truncating the fractional portion results in an ƒ(NCO) equal to 5.0199995 MHz, which is not the
desired frequency.
To produce the desired frequency, the NCO_RDIV parameter is used to force the phase accumulator to arrive at
specific frequencies without error. First, select a frequency step size (ƒ(STEP)) that is appropriate for the NCO
frequency steps required. The typical value of ƒ(STEP) is 10 kHz. Next, use Equation 5 to program the NCO_RDIV
value.
NCO _ RDIV =
(¦DEVCLK
/ ¦ STEP )
64
(5)
The result of Equation 5 must be an integer value. If the value is not an integer, adjust either of the parameters
until the result is an integer value.
For example, select a value of 1920 for NCO_RDIV.
NOTE
NCO_RDIV values larger than 8192 can degrade the NCO SFDR performance and are
not recommended.
Now use Equation 6 to calculate the FREQAx register value.
(
FREQAx = round 232 ´ ¦NCO / ¦DEVCLK
)
Alternatively, the following equations can be used:
¦(NCO)
N
¦(STEP)
(
FREQAx = round 2
48
26
´ N / NCO_RDIV
)
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(7)
(8)
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Table 10 lists common values for NCO_RDIV in 10-kHz frequency steps.
Table 10. Common NCO_RDIV Values (For 10-kHz Frequency Steps)
fCLK (MHz)
NCO_RDIV
2457.6
3840
1966.08
3072
1600
2500
1474.56
2304
1228.8
1920
7.3.7.1.5 NCO Phase Offset Setting
The NCO phase-offset setting for each NCO is set by the 16-bit register value PHASEAx and PHASEBx (where
x = 0 to 3). The value is left-justified into a 32-bit field and then added to the phase accumulator.
Use Equation 9 to calculate the phase offset in radians.
Φ(rad) = PHASEA/Bx × 2–16 × 2 × π (x = 0 to 3)
(9)
7.3.7.1.6 NCO Phase Synchronization
The NCOs must be synchronized after setting or changing the value of FREQAx or FREQBx. NCO
synchronization is performed when the JESD204B link is initialized or by SYSREF, based on the settings of
NCO_SYNC_ILA and NCO_SYNC_NEXT. The procedures are as follows for the JESD204B initialization
procedure and the SYSREF procedure for both DC-coupled and AC-coupled SYSREF signals.
NCO synchronization using the JESD204B SYNC signal (SYNCSE or TMSTP±):
1. The device must be programmed for normal operation
2. Set NCO_SYNC_ILA to 1 to enable NCO synchronization using the SYNC signal
3. Set JESD_EN to 0
4. Program FREQAx, FREQBx, PHASEAx, and PHASEBx to the desired settings
5. In the JESD204B receiver (logic device), deassert the SYNC signal by setting SYNC high
6. Set JESD_EN to 1
7. Assert the SYNC signal by setting SYNC low in the JESD204B receiver to start the code group
synchronization (CGS) process
8. After achieving CGS, deassert the SYNC signal by setting SYNC high at the same time for all ADCs to be
synchronized and verify that the SYNC setup and hold times are met (as specified in the Timing
Requirements table)
NCO synchronization using SYSREF (DC-coupled):
1. The device must be programmed for normal operation
2. Set JESD_EN to 1 to start the JESD204B link (the SYNC signal can respond as normal during the CGS
process)
3. Program NCO_SYNC_ILA=0 on all devices.
4. Issue one or more SYSREF pulses to all ADCs to synchronize the local multiframe clock. Verify that
SYSREF is disabled (held low) before continuing.
5. Program FREQAx, FREQBx, PHASEAx, and PHASEBx to the desired settings
6. Write NCO_SYNC_NEXT to 0.
7. Arm NCO synchronization by setting NCO_SYNC_NEXT to 1
8. Issue a single SYSREF pulse to all ADCs to synchronize NCOs within all devices. The SYSREF pulse must
have the same phase relationship to the LMFC as the SYSREF pulse(s) from step 4 above.
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NCO synchronization using SYSREF (AC-coupled):
1. The device must be programmed for normal operation
2. Set JESD_EN to 1 to start the JESD204B link (the SYNC signal can respond as normal during the CGS
process)
3. Program NCO_SYNC_ILA=0 on all devices.
4. Enable the SYSREF generator for all ADCs to synchronize the local multiframe clock. Leave SYSREF
running contniuously.
5. Program FREQAx, FREQBx, PHASEAx, and PHASEBx to the desired settings
6. Write NCO_SYNC_NEXT to 0.
7. Arm NCO synchronization by setting NCO_SYNC_NEXT to 1 at the same time at all ADCs by timing the
rising edge of SCLK for the last data bit (LSB) at the end of the SPI write so that the SCLK rising edge
occurs after a SYSREF rising edge and early enough before the next SYSREF rising edge so that the trigger
is armed before the next SYSREF rising edge (a long SYSREF period is recommended)
8. NCOs in all ADCs are synchronized by the next SYSREF rising edge
7.3.7.2 Decimation Filters
The decimation filters are arranged to provide a programmable overall decimation of 2, 4, 8, or 16. All filter
outputs have a resolution of 15 bits. The decimate-by-2 filter has a real output and the decimate-by-4, decimateby-8, and decimate-by-16 filters have complex outputs. Table 11 lists the effective output sample rates, available
signal bandwidths, output formats, and stop-band attenuation for each decimation mode. The available
bandwidths of the complex output modes are twice that of equivalent real decimation modes because of the
nature of the I/Q data and complex signaling. This higher bandwidth results in the decimate-by-2 real and
decimate-by-4 complex modes having approximately the same useful output bandwidth.
Table 11. Output Sample Rates and Signal Bandwidths
DECIMATION
SETTING
ƒ(DEVCLK)
OUTPUT FORMAT
OUTPUT RATE
(MSPS)
MAX ALIAS PROTECTED SIGNAL
BANDWIDTH (MHz)
STOP-BAND
ATTENUATION
PASS-BAND
RIPPLE
No decimation
ƒ(DEVCLK)
ƒ(DEVCLK) / 2
—
< ±0.001 dB
Real signal,
12-bit data
Decimate-by-2
ƒ(DEVCLK) / 2
0.4 × ƒ(DEVCLK) / 2
> 89 dB
< ±0.001 dB
Real signal,
15-bit data
Decimate-by-4
(D4_AP87 = 0)
ƒ(DEVCLK) / 4
0.8 × ƒ(DEVCLK) / 4
> 90 dB
< ±0.001 dB
Complex signal,
15-bit data
Decimate-by-4
(D4_AP87 = 1)
ƒ(DEVCLK) / 4
0.875 × ƒ(DEVCLK) / 4
> 66 dB
< ±0.005 dB
Complex signal,
15-bit data
Decimate-by-8
ƒ(DEVCLK) / 8
0.8 × ƒ(DEVCLK) / 8
> 90 dB
< ±0.001 dB
Complex signal,
15-bit data
Decimate-by-16
ƒ(DEVCLK) / 16
0.8 × ƒ(DEVCLK) / 16
> 90 dB
< ±0.001 dB
Complex signal,
15-bit data
Figure 69 to Figure 80 provide the composite decimation filter responses. The pass-band section (black trace)
shows the alias-protected region of the response. The transition band (red trace) shows the transition region of
the response, or the regions that alias into the transition region, which is not alias protected and therefore
desired signals must not be within this band. The aliasing band (blue trace) shows the attenuation applied to the
bands that alias back into the pass band after decimation and are sufficiently low to prevent undesired signals
from showing up in the pass band. Use analog input filtering for additional attenuation of the aliasing band or to
prevent harmonics, interleaving spurs, or other undesired spurious signals from folding into the desired signal
band before the decimation filter.
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0
0.001
Passband
Transition Band
Aliasing Band
-20
Passband
Transition Band
Attenuation (dB)
Attenuation (dB)
0.0005
-40
-60
-80
0
-0.0005
-100
-120
-0.001
0
0.1
0.2
0.3
Normalized Frequency (Fs)
0.4
0.5
0
0.05
h2co
Figure 69. Decimate-by-2 Composite Response
(D2_HIGH_PASS = 0)
0.1
0.15
Normalized Frequency (Fs)
0.2
0.25
h2co
Figure 70. Decimate-by-2 Composite Zoomed Pass-Band
Response (D2_HIGH_PASS = 0)
0
0.001
Passband
Transition Band
Aliasing Band
-20
Passband
Transition Band
Aliasing Band
Attenuation (dB)
Attenuation (dB)
0.0005
-40
-60
-80
0
-0.0005
-100
-120
0
0.1
0.2
0.3
Normalized Frequency (Fs)
0.4
-0.001
0.25
0.5
0.3
h2co
Figure 71. Decimate-by-2 Composite Response
(D2_HIGH_PASS = 1)
0.35
0.4
Normalized Frequency (Fs)
0.45
0.5
h2co
Figure 72. Decimate-by-2 Composite Zoomed Pass-Band
Response (D2_HIGH_PASS = 1)
0
0.001
Passband
Transition Band
Aliasing Band
-20
Passband
Transition Band
Attenuation (dB)
Attenuation (dB)
0.0005
-40
-60
-80
0
-0.0005
-100
-120
-0.001
0
0.1
0.2
0.3
Normalized Frequency (Fs)
0.4
0.5
0
h4co
Figure 73. Decimate-by-4 Composite Response
(D4_AP87 = 0)
0.02
0.04
0.06
0.08
Normalized Frequency (Fs)
0.1
0.12
h4co
Figure 74. Decimate-by-4 Composite Zoomed Pass-Band
Response (D4_AP87 = 0)
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0
0.01
Passband
Transition Band
Aliasing Band
-20
Passband
Transition Band
Attenuation (dB)
Attenuation (dB)
0.005
-40
-60
-80
0
-0.005
-100
-120
-0.01
0
0.1
0.2
0.3
Normalized Frequency (Fs)
0.4
0.5
0
0.02
h4_9
Figure 75. Decimate-by-4 Composite Response
(D4_AP87 = 1)
0.04
0.06
0.08
Normalized Frequency (Fs)
0.1
0.12
h4_9
Figure 76. Decimate-by-4 Composite Zoomed Pass-Band
Response (D4_AP87 = 1)
0
0.001
Passband
Transition Band
Aliasing Band
-20
Passband
Transition Band
Attenuation (dB)
Attenuation (dB)
0.0005
-40
-60
-80
0
-0.0005
-100
-120
-0.001
0
0.1
0.2
0.3
Normalized Frequency (Fs)
0.4
0.5
0
0.01
h8co
Figure 77. Decimate-by-8 Composite Response
0.02
0.03
0.04
Normalized Frequency (Fs)
0.05
0.06
h8co
Figure 78. Decimate-by-8 Composite Zoomed Pass-Band
Response
0
0.001
Passband
Transition Band
Aliasing Band
-20
Passband
Transition Band
Attenuation (dB)
Attenuation (dB)
0.0005
-40
-60
-80
0
-0.0005
-100
-120
-0.001
0
0.1
0.2
0.3
Normalized Frequency (Fs)
0.4
0.5
Figure 79. Decimate-by-16 Composite Response
52
0
h16c
0.005
0.01
0.015
0.02
Normalized Frequency (Fs)
0.025
0.03
h16c
Figure 80. Decimate-by-16 Composite Zoomed Pass-Band
Response
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For maximum efficiency, a group of high-speed filter blocks are implemented with specific blocks used for each
decimation setting to achieve the composite responses illustrated in Figure 69 to Figure 80. Table 12 describes
the combination of filter blocks used for each decimation setting and Table 13 lists the coefficient details and
decimation factor of each filter block. The coefficients are symmetric with the center tap indicated by bold text.
Table 12. Decimation Mode Filter Usage
DECIMATION SETTING
FILTER BLOCKS USED
2
CS80
4 (D4_AP87 = 0)
CS45, CS80
4 (D4_AP87 = 1)
CS45, CS87
8
CS20, CS40, CS80
16
CS10, CS20, CS40, CS80
Table 13. Filter Coefficient Details
FILTER COEFFICIENT SET (Decimation Factor of Filter)
CS10 (2)
CS20 (2)
CS40 (2)
CS45 (2)
CS80 (2)
CS87 (2)
–65
–65
109
109
–327
–327
56
56
–37
–37
–15
0
0
0
0
0
0
0
0
0
0
0
0
577
577
–837
–837
2231
2231
–401
–401
118
118
23
23
1024
–15
0
0
0
0
0
0
0
0
0
0
4824
4824
–8881
–8881
1596
1596
–291
–291
–40
–40
8192
0
0
0
0
0
0
0
0
39742
39742
–4979
–4979
612
612
64
64
65536
0
0
0
0
0
0
20113
20113
–1159
–1159
–97
–97
32768
0
0
0
0
2031
2031
142
142
0
0
0
0
–3356
–3356
–201
–201
0
0
0
0
5308
5308
279
279
0
0
0
0
–8140
–8140
–380
–380
0
0
0
0
12284
12284
513
513
0
0
0
0
–18628
–18628
–690
–690
0
0
0
0
29455
29455
939
939
0
0
0
0
–53191
–53191
–1313
–1313
0
0
0
0
166059
166059
1956
1956
262144
0
0
–3398
–3398
0
0
10404
10404
16384
7.3.7.3 Output Data Format
The DDC output data varies depending on the selected JMODE. Real decimate-by-2 mode (JMODE 9) consists
of 15-bit real output data. Complex decimation modes (JMODE 10 to 16), except for JMODE 12, consist of 15-bit
complex data plus the two overrange threshold-detection control bits. JMODE 12 output data consists of 12-bit
complex data, but does not include the two overrange threshold-detection control bits that must instead be
monitored using the ORA0, ORA1 and ORB0, ORB1 output pins. Table 14 lists the data format for JMODE 9 and
Table 15 lists the data format for all JMODEs except JMODE 12.
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Table 14. Real Decimation (JMODE 9) Output Sample Format
DDC
CHANNEL
ODD,
EVEN
SAMPLE
A
Even
16-BIT OUTPUT WORD
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
DDC A even-numbered sample, 15-bit output data
OVR_T0
A
Odd
DDC A odd-numbered sample, 15-bit output data
OVR_T1
B
Even
DDC B even-numbered sample, 15-bit output data
OVR_T0
B
Odd
DDC B odd-numbered sample, 15-bit output data
OVR_T1
Table 15. Complex Decimation Output Sample Format (Except JMODE 12)
I/Q
SAMPLE
16-BIT OUTPUT WORD
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
I
DDC in-phase (I) 15-bit output data
OVR_T0
Q
DDC quadrature (Q) 15-bit output data
OVR_T1
7.3.7.4 Decimation Settings
7.3.7.4.1 Decimation Factor
The decimation setting is adjustable over the following settings and is set by the JMODE parameter. See
Table 19 for the available JMODE values and the corresponding decimation settings.
• DDC Bypass: No decimation, real output
• Decimate-by-2: Real output (JMODE 9)
• Decimate-by-4: Complex output (JMODE 10 to 12)
• Decimate-by-8: Complex output (JMODE 13 to 14)
• Decimate-by-16: Complex output (JMODE 15 to 16)
7.3.7.4.2 DDC Gain Boost
The DDC gain boost (see the DDC configuration register) provides additional gain through the DDC block.
Setting BOOST to 1 sets the total decimation filter chain gain to 6.02 dB. With a setting of 0, the total decimation
filter chain has a 0-dB gain. Only use this setting when the negative image of the input signal is filtered out by the
decimation filters, otherwise clipping may occur. There is no reduction in analog performance when gain boost is
enabled or disabled, but care must be taken to understand the reference output power for proper performance
calculations.
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7.3.8 JESD204B Interface
The ADC12DJ2700 uses the JESD204B high-speed serial interface for data converters to transfer data from the
ADC to the receiving logic device. The ADC12DJ2700 serialized lanes are capable of operating up to 12.8 Gbps,
slightly above the JESD204B maximum lane rate. A maximum of 16 lanes can be used to allow lower lane rates
for interfacing with speed-limited logic devices. Figure 81 shows a simplified block diagram of the JESD204B
interface protocol.
ADC
JESD204B Block
ADC
JESD204B
TRANSPORT
LAYER
SCRAMBLER
(Optional)
JESD204B
LINK LAYER
8b/10b
ENCODER
JESD204B
TX
ANALOG
CHANNEL
Logic Device
JESD204B Block
APPLICATION
LAYER
JESD204B
TRANSPORT
LAYER
DESCRAMBLE
(Optional)
JESD204B
LINK LAYER
8b/10b
DECODER
JESD204B
RX
Figure 81. Simplified JESD204B Interface Diagram
The various signals used in the JESD204B interface and the associated ADC12DJ2700 pin names are
summarized briefly in Table 16 for reference.
Table 16. Summary of JESD204B Signals
SIGNAL NAME
Data
SYNC
Device clock
SYSREF
ADC12DJ2700 PIN NAMES
DESCRIPTION
DA[7:0]+, DA[7:0]–, DB[7:0]+, DB[7:0]–)
High-speed serialized data after 8b,
10b encoding
SYNCSE, TMSTP+, TMSTP–
Link initialization signal, toggles low to
start code group synchronization
(CGS) process
CLK+, CLK–
ADC sampling clock, also used for
clocking digital logic and output
serializers
SYSREF+, SYSREF–
System timing reference used to
deterministically reset the internal local
multiframe counters in each
JESD204B device
7.3.8.1 Transport Layer
The transport layer takes samples from the ADC output (in decimation bypass mode) or from the DDC output
and maps the samples into octets, frames, multiframes, and lanes. Sample mapping is defined by the JESD204B
mode that is used, defined by parameters such as L, M, F, S, N, N', CF, and so forth. There are a number of
predefined transport layer modes in the ADC12DJ2700 that are defined in Table 19. The high level configuration
parameters for the transport layer in the ADC12DJ2700 are described in Table 17. For simplicity, the transport
layer mode is chosen by simply setting the JMODE parameter and the desired K value. For reference, the
various configuration parameters for JESD204B are defined in Table 18.
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7.3.8.2 Scrambler
An optional data scrambler can be used to scramble the octets before transmission across the channel.
Scrambling is recommended in order to remove the possibility of spectral peaks in the transmitted data. The
JESD204B receiver automatically synchronizes its descrambler to the incoming scrambled data stream. The
initial lane alignment sequence (ILA) is never scrambled. Scrambling can be enabled by setting SCR (in the
JESD204B control register).
7.3.8.3 Link Layer
The link layer serves multiple purposes in JESD204B, including establishing the code boundaries (see the Code
Group Synchronization (CGS) section), initializing the link (see the Initial Lane Alignment Sequence (ILAS)
section), encoding the data (see the 8b, 10b Encoding section), and monitoring the health of the link (see the
Frame and Multiframe Monitoring section).
7.3.8.3.1 Code Group Synchronization (CGS)
The first step in initializing the JESD204B link, after SYSREF is processed, is to achieve code group
synchronization. The receiver first asserts the SYNC signal when ready to initialize the link. The transmitter
responds to the request by sending a stream of K28.5 characters. The receiver then aligns its character clock to
the K28.5 character sequence. Code group synchronization is achieved after receiving four K28.5 characters
successfully. The receiver deasserts SYNC on the next local multiframe clock (LMFC) edge after CGS is
achieved and waits for the transmitter to start the initial lane alignment sequence.
7.3.8.3.2 Initial Lane Alignment Sequence (ILAS)
After the transmitter detects the SYNC signal deassert, the transmitter waits until its next LMFC edge to start
sending the initial lane alignment sequence. The ILAS consists of four multiframes each containing a
predetermined sequence. The receiver searches for the start of the ILAS to determine the frame and multiframe
boundaries. As the ILAS reaches the receiver for each lane, the lane starts to buffer its data until all receivers
have received the ILAS and subsequently release the ILAS from all lanes at the same time in order to align the
lanes. The second multiframe of the ILAS contains configuration parameters for the JESD204B that can be used
by the receiver to verify that the transmitter and receiver configurations match.
7.3.8.3.3 8b, 10b Encoding
The data link layer converts the 8-bit octets from the transport layer into 10-bit characters for transmission across
the link using 8b, 10b encoding. 8b, 10b encoding provides DC balance for AC-coupling of the SerDes links and
a sufficient number of edge transitions for the receiver to reliably recover the data clock. 8b, 10b also provides
some amount of error detection where a single bit error in a character likely results in either not being able to find
the 10-bit character in the 8b, 10b decoder lookup table or incorrect character disparity.
7.3.8.3.4 Frame and Multiframe Monitoring
The ADC12DJ2700 supports frame and multiframe monitoring for verifying the health of the JESD204B link. If
the last octet of a frame matches the last octet of the previous frame, then the last octet in the second frame is
replaced with an /F/ (/K28.7/) character. If the second frame is the last frame of a multiframe, then an /A/
(/K28.3/) character is used instead. When scrambling is enabled, if the last octet of a frame is 0xFC then the
transmitter replaces the octet with an /F/ (/K28.7/) character. With scrambling, if the last octet of a multiframe is
0x7C then the transmitter replaces the octet with an /A/ (/K28.3/) character. When the receiver detects an /F/ or
/A/ character, the receiver checks if the character occurs at the end of a frame or multiframe, and replaces that
octet with the appropriate data character. The receiver can report an error if the alignment characters occur in
the incorrect place and trigger a link realignment.
7.3.8.4 Physical Layer
The JESD204B physical layer consists of a current mode logic (CML) output driver and receiver. The receiver
consists of a clock detection and recovery (CDR) unit to extract the data clock from the serialized data stream
and can contain an equalizer to correct for the low-pass response of the physical transmission channel. Likewise,
the transmitter can contain pre-equalization to account for frequency dependent losses across the channel. The
total reach of the SerDes links depends on the data rate, board material, connectors, equalization, noise and
jitter, and required bit-error performance. The SerDes lanes do not have to be matched in length because the
receiver aligns the lanes during the initial lane alignment sequence.
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7.3.8.4.1 SerDes Pre-Emphasis
The ADC12DJ2700 high-speed output drivers can pre-equalize the transmitted data stream by using preemphasis in order to compensate for the low-pass response of the transmission channel. Configurable preemphasis settings allow the output drive waveform to be optimized for different PCB materials and signal
transmission distances. The pre-emphasis setting is adjusted through the serializer pre-emphasis setting
SER_PE (in the serializer pre-emphasis control register). Higher values increase the pre-emphasis to
compensate for more lossy PCB materials. This adjustment is best used in conjunction with an eye-diagram
analysis capability in the receiver. Adjust the pre-emphasis setting to optimize the eye-opening for the specific
hardware configuration and line rates needed.
7.3.8.5 JESD204B Enable
The JESD204B interface must be disabled through JESD_EN (in the JESD204B enable register) while any of the
other JESD204B parameters are being changed. When JESD_EN is set to 0 the block is held in reset and the
serializers are powered down. The clocks for this section are also gated off to further save power. When the
parameters are set as desired, the JESD204B block can be enabled (JESD_EN is set to 1).
7.3.8.6 Multi-Device Synchronization and Deterministic Latency
JESD204B subclass 1 outlines a method to achieve deterministic latency across the serial link. If two devices
achieve the same deterministic latency then they can be considered synchronized. This latency must be
achieved from system startup to startup to be deterministic. There are two key requirements to achieve
deterministic latency. The first is proper capture of SYSREF for which the ADC12DJ2700 provides a number of
features to simplify this requirement at giga-sample clock rates (see the SYSREF Capture for Multi-Device
Synchronization and Deterministic Latency section for more information).
The second requirement is to choose a proper elastic buffer release point in the receiver. Because the
ADC12DJ2700 is an ADC, the ADC12DJ2700 is the transmitter (TX) in the JESD204B link and the logic device
is the receiver (RX). The elastic buffer is the key block for achieving deterministic latency, and does so by
absorbing variations in the propagation delays of the serialized data as the data travels from the transmitter to
the receiver. A proper release point is one that provides sufficient margin against delay variations. An incorrect
release point results in a latency variation of one LMFC period. Choosing a proper release point requires
knowing the average arrival time of data at the elastic buffer, referenced to an LMFC edge, and the total
expected delay variation for all devices. With this information the region of invalid release points within the LMFC
period can be defined, which stretches from the minimum to maximum delay for all lanes. Essentially, the
designer must ensure that the data for all lanes arrives at all devices before the release point occurs.
Figure 82 provides a timing diagram that demonstrates this requirement. In this figure, the data for two ADCs is
shown. The second ADC has a longer routing distance (tPCB) and results in a longer link delay. First, the invalid
region of the LMFC period is marked off as determined by the data arrival times for all devices. Then, the release
point is set by using the release buffer delay (RBD) parameter to shift the release point an appropriate number of
frame clocks from the LMFC edge so that the release point occurs within the valid region of the LMFC cycle. In
the case of Figure 82, the LMFC edge (RBD = 0) is a good choice for the release point because there is
sufficient margin on each side of the valid region.
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Nominal Link Delay
(Arrival at Elastic Buffer)
ADC 1 Data
Propagation
tTX
ADC 2 Data
Propagation
tTX
tPCB
Link Delay
Variation
tRX-DESER
tPCB
tRX-DESER
Release point
margin
Choose LMFC
edge as release
point (RBD = 0)
TX LMFC
RX LMFC
Time
Invalid Region
of LMFC
Valid Region
of LMFC
Figure 82. LMFC Valid Region Definition for Elastic Buffer Release Point Selection
The TX and RX LMFCs do not necessarily need to be phase aligned, but knowledge of their phase is important
for proper elastic buffer release point selection. Also, the elastic buffer release point occurs within every LMFC
cycle, but the buffers only release when all lanes have arrived. Therefore, the total link delay can exceed a single
LMFC period; see JESD204B multi-device synchronization: Breaking down the requirements for more
information.
7.3.8.7 Operation in Subclass 0 Systems
The ADC12DJ2700 can operate with subclass 0 compatibility provided that multi-ADC synchronization and
deterministic latency are not required. With these limitations, the device can operate without the application of
SYSREF. The internal local multiframe clock is automatically self-generated with unknown timing. SYNC is used
as normal to initiate the CGS and ILA.
7.3.9 Alarm Monitoring
A number of built-in alarms are available to monitor internal events. Several types of alarms and upsets are
detected by this feature:
1. Serializer PLL is not locked
2. JESD204B link is not transmitting data (not in the data transmission state)
3. SYSREF causes internal clocks to be realigned
4. An upset that impacts the NCO
5. An upset that impacts the internal clocks
When an alarm occurs, a bit for each specific alarm is set in ALM_STATUS. Each alarm bit remains set until the
host system writes a 1 to clear the alarm. If the alarm type is not masked (see the alarm mask register), then the
alarm is also indicated by the ALARM register. The CALSTAT output pin can be configured as an alarm output
that goes high when an alarm occurs; see the CAL_STATUS_SEL bit in the calibration pin configuration register.
7.3.9.1 NCO Upset Detection
The NCO_ALM register bit indicates if the NCO in channel A or B has been upset. The NCO phase accumulators
in channel A are continuously compared to channel B. If the accumulators differ for even one clock cycle, the
NCO_ALM register bit is set and remains set until cleared by the host system by writing a 1. This feature
requires the phase and frequency words for each NCO accumulator in DDC A (PHASEAx, FREQAx) to be set to
the same values as the NCO accumulators in DDC B (PHASEBx, FREQBx). For example, PHASEA0 must be
the same as PHASEB0 and FREQA0 must be the same as FREQB0, however, PHASEA1 can be set to a
different value than PHASEA0. This requirement ultimately reduces the number of NCO frequencies available for
phase coherent frequency hopping from four to two for each DDC. DDC B can use a different NCO frequency
than DDC A by setting the NCOB[1:0] pins to a different value than NCOA[1:0]. This detection is only valid after
the NCOs are synchronized by either SYSREF or the start of the ILA sequence (as determined by the NCO
synchronization register). For the NCO upset detection to work properly, follow these steps:
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1.
2.
3.
4.
Program JESD_EN = 0
Ensure the device is configured to use both channels (PD_ACH = 0, PD_BCH = 0)
Select a JMODE that uses the NCO
Program all NCO frequencies and phases to be the same for channel A and B (for example, FREQA0 =
FREQB0, FREQA1 = FREQB1, FREQA2 = FREQB2, and FREQA3 = FREQB3)
5. If desired, use the CMODE and CSEL registers or the NCOA[1:0] and NCOB[1:0] pins to choose a unique
frequency for channel A and channel B
6. Program JESD_EN = 1
7. Synchronize the NCOs (using the ILA or using SYSREF); see the NCO synchronization register
8. Write a 1 to the NCO_ALM register bit to clear it
9. Monitor the NCO_ALM status bit or the CALSTAT output pin if CAL_STATUS_SEL is properly configured
10. If the frequency or phase registers are changed while the NCO is enabled, the NCOs can get out of
synchronization
11. Repeat steps 7-9
12. If the device enters and exits global power down, repeat steps 7-9
7.3.9.2 Clock Upset Detection
The CLK_ALM register bit indicates if the internal clocks have been upset. The clocks in channel A are
continuously compared to channel B. If the clocks differ for even one DEVCLK / 2 cycle, the CLK_ALM register
bit is set and remains set until cleared by the host system by writing a 1. For the CLK_ALM register bit to function
properly, follow these steps:
1.
2.
3.
4.
5.
6.
Program JESD_EN = 0
Ensure the part is configured to use both channels (PD_ACH = 0, PD_BCH = 0)
Program JESD_EN = 1
Write CLK_ALM = 1 to clear CLK_ALM
Monitor the CLK_ALM status bit or the CALSTAT output pin if CAL_STATUS_SEL is properly configured
When exiting global power-down (via MODE or the PD pin), the CLK_ALM status bit may be set and must be
cleared by writing a 1 to CLK_ALM
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7.4 Device Functional Modes
The ADC12DJ2700 can be configured to operate in a number of functional modes. These modes are described
in this section.
7.4.1 Dual-Channel Mode
The ADC12DJ2700 can be used as a dual-channel ADC where the sampling rate is equal to the clock frequency
(fS = fCLK) provided at the CLK+ and CLK– pins. The two inputs, INA± and INB±, serve as the respective inputs
for each channel in this mode. This mode is chosen simply by setting JMODE to the appropriate setting for the
desired configuration as described in Table 19. The analog inputs can be swapped by setting DUAL_INPUT (see
the input mux control register)
7.4.2 Single-Channel Mode (DES Mode)
The ADC12DJ2700 can also be used as a single-channel ADC where the sampling rate is equal to two times the
clock frequency (fS = 2 × fCLK) provided at the CLK+ and CLK– pins. This mode effectively interleaves the two
ADC channels together to form a single-channel ADC at twice the sampling rate. This mode is chosen simply by
setting JMODE to the appropriate setting for the desired configuration as described in Table 19. Either analog
input, INA± or INB±, can serve as the input to the ADC, however INA± is recommended for best performance.
The analog input can be selected using SINGLE_INPUT (see the input mux control register). The digital downconverters cannot be used in single-channel mode.
NOTE
INA± is strongly recommended to be used as the input to the ADC for optimized
performance in single-channel mode.
7.4.3 JESD204B Modes
The ADC12DJ2700 can be programmed as a single-channel or dual-channel ADC, with or without decimation,
and a number JESD204B output formats. Table 17 summarizes the basic operating mode configuration
parameters and whether they are user configured or derived.
NOTE
Powering down high-speed data outputs (DA0± ... DA7±, DB0± ... DB7±) for extended
times can reduce performance of the output serializers, especially at high data rates. For
information regarding reliable serializer operation, see the Power-Down Modes section.
Table 17. ADC12DJ2700 Operating Mode Configuration Parameters
PARAMETER
DESCRIPTION
USER CONFIGURED
OR DERIVED
VALUE
JMODE
JESD204B operating mode, automatically
derives the rest of the JESD204B
parameters, single-channel or dual-channel
mode and the decimation factor
User configured
Set by JMODE (see the JESD204B mode
register)
D
Decimation factor
Derived
See Table 19
DES
1 = single-channel mode, 0 = dual-channel
mode
Derived
See Table 19
R
Number of bits transmitted per lane per
DEVCLK cycle. The JESD204B line rate is
the DEVCLK frequency times R. This
parameter sets the SerDes PLL
multiplication factor or controls bypassing of
the SerDes PLL.
Derived
See Table 19
Links
Number of JESD204B links used
Derived
See Table 19
K
Number of frames per multiframe
User configured
Set by KM1 (see the JESD204B K
parameter register), see the allowed values
in Table 19
60
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There are a number of parameters required to define the JESD204B format, all of which are sent across the link
during the initial lane alignment sequence. In the ADC12DJ2700, most parameters are automatically derived
based on the selected JMODE; however, a few are configured by the user. Table 18 describes these
parameters.
Table 18. JESD204B Initial Lane Alignment Sequence Parameters
PARAMETER
DESCRIPTION
USER CONFIGURED
OR DERIVED
VALUE
ADJCNT
LMFC adjustment amount (not applicable)
Derived
Always 0
ADJDIR
LMFC adjustment direction (not applicable)
Derived
Always 0
BID
Bank ID
Derived
Always 0
CF
Number of control words per frame
Derived
Always 0
CS
Control bits per sample
Derived
Always set to 0 in ILAS, see Table 19 for
actual usage
DID
Device identifier, used to identify the link
User configured
Set by DID (see the JESD204B DID
parameter register), see Table 20
F
Number of octets (bytes) per frame (per
lane)
Derived
See Table 19
HD
High-density format (samples split between
lanes)
Derived
Always 0
JESDV
JESD204 standard revision
Derived
Always 1
K
Number of frames per multiframe
User configured
Set by the KM1 register, see the JESD204B
K parameter register
L
Number of serial output lanes per link
Derived
See Table 19
LID
Lane identifier for each lane
Derived
See Table 20
M
Number of converters used to determine
lane bit packing; may not match number of
ADC channels in the device
Derived
See Table 19
N
Sample resolution (before adding control
and tail bits)
Derived
See Table 19
N'
Bits per sample after adding control and tail
bits
Derived
See Table 19
S
Number of samples per converter (M) per
frame
Derived
See Table 19
SCR
Scrambler enabled
User configured
Set by the JESD204B control register
SUBCLASSV
Device subclass version
Derived
Always 1
RES1
Reserved field 1
Derived
Always 0
RES2
Reserved field 2
Derived
Always 0
CHKSUM
Checksum for ILAS checking (sum of all
above parameters modulo 256)
Derived
Computed based on parameters in this table
Configuring the ADC12DJ2700 is made easy by using a single configuration parameter called JMODE (see the
JESD204B mode register). Using Table 19, the correct JMODE value can be found for the desired operating
mode. The modes listed in Table 19 are the only available operating modes. This table also gives a range and
allowable step size for the K parameter (set by KM1, see the JESD204B K parameter register), which sets the
multiframe length in number of frames.
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Table 19. ADC12DJ2700 Operating Modes
USER-SPECIFIED
PARAMETER
ADC12DJ2700 OPERATING MODE
DERIVED PARAMETERS
INPUT CLOCK
RANGE (MHz)
N’
L
(Per
Link)
M
(Per
Link)
F
S
R
(Fbit / Fclk)
0
12
4
4 (1)
8
5
4
800-2700
12
0
12
8
8 (1)
8
5
2
800-2700
2
12
0
12
4
4 (1)
8
5
4
800-2700
0
2
12
0
12
8
8 (1)
8
5
2
800-2700
1
1
2
8
0
8
2
1
1
2
5
800-2560
1
1
2
8
0
8
4
1
1
4
2.5
800-2700
1
0
2
8
0
8
2
1
1
2
5
800-2560
1
4
2.5
800-2700
—
—
—
—
2
4
2.5
800-2700
2
2
1
5
800-2560
2
2
2
2.5
800-2700
8
8 (1)
8
5
1
1000-2700
16
1
2
4
1
5
800-2560
JMODE
K
[Min:Step:Max]
D
DES
LINKS
N
CS
12-bit, single-channel, 8 lanes
0
3:1:32
1
1
2
12
12-bit, single-channel, 16 lanes
1
3:1:32
1
1
2
12-bit, dual-channel, 8 lanes
2
3:1:32
1
0
12-bit, dual-channel, 16 lanes
3
3:1:32
1
8-bit, single-channel, 4 lanes
4
18:2:32
8-bit, single-channel, 8 lanes
5
18:2:32
8-bit, dual-channel, 4 lanes
6
18:2:32
8-bit, dual-channel, 8 lanes
7
18:2:32
1
0
2
8
0
8
4
1
Reserved
8
—
—
—
—
—
—
—
—
—
15-bit, real data, decimate-by-2, 8 lanes
9
9:1:32
2
0
2
15
1 (2)
16
4
1
15-bit, decimate-by-4, 4 lanes
10
9:1:32
4
0
2
15
1 (2)
16
2
15-bit, decimate-by-4, 8 lanes
11
9:1:32
4
0
2
15
1 (2)
16
4
12-bit, decimate-by-4, 16 lanes
12
3:1:32
4
0
2
12
0
12
15-bit, decimate-by-8, 2 lanes
13
5:1:32
8
0
2
15
1 (2)
(2)
15-bit, decimate-by-8, 4 lanes
14
9:1:32
8
0
2
15
1
16
2
2
2
1
2.5
800-2700
15-bit, decimate-by-16, 1 lane
15
3:1:32
16
0
1
15
1 (2)
16
1
4
8
1
5
800-2560
15-bit, decimate-by-16, 2 lanes
16
5:1:32
16
0
2
15
1 (2)
16
1
2
4
1
2.5
800-2700
8-bit, single-channel, 16 lanes
17
18:2:32
1
1
2
8
0
8
8
1
1
8
1.25
800-2700
8-bit, dual-channel, 16 lanes
18
18:2:32
1
0
2
8
0
8
8
1
1
8
1.25
800-2700
(1)
(2)
62
M equals L in these modes to allow the samples to be sent in time-order over L lanes. The M parameter does not represent the actual number of converters. Interleave the M sample
streams from each link in the receiver to produce the correct sample data; see Table 21 to Table 38 for more details.
CS is always reported as 0 in the initial lane alignment sequence (ILAS) for the ADC12DJ2700.
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The ADC12DJ2700 has a total of 16 high-speed output drivers that are grouped into two 8-lane JESD204B links.
Most operating modes use two links with up to eight lanes per link. The lanes and their derived configuration
parameters are described in Table 20. For a specified JMODE, the lowest indexed lanes for each link are used
and the higher indexed lanes for each link are automatically powered down. Always route the lowest indexed
lanes to the logic device.
Table 20. ADC12DJ2700 Lane Assignment and Parameters
DEVICE PIN
DESIGNATION
LINK
DID (User Configured)
LID (Derived)
DA0±
0
DA1±
1
DA2±
DA3±
DA4±
2
Set by DID (see the JESD204B DID parameter
register), the effective DID is equal to the DID register
setting (DID)
A
3
4
DA5±
5
DA6±
6
DA7±
7
DB0±
0
DB1±
1
DB2±
DB3±
DB4±
2
Set by DID (see the JESD204B DID parameter
register), the effective DID is equal to the DID register
setting plus 1 (DID+1)
B
3
4
DB5±
5
DB6±
6
DB7±
7
7.4.3.1 JESD204B Output Data Formats
Output data are formatted in a specific optimized fashion for each JMODE setting. When the DDC is not used
(decimation = 1) the 12-bit offset binary values are mapped into octets. For the DDC mode, the 16-bit values (15bit complex data plus 1 overrange bit) are mapped into octets. The following tables show the specific mapping
formats for a single frame. In all mappings the tail bits (T) are 0 (zero). In Table 21 to Table 38, the singlechannel format samples are defined as Sn, where n is the sample number within the frame. In the dual-channel
real output formats (DDC bypass and decimate-by-2), the samples are defined as An and Bn, where An are
samples from channel A and Bn are samples from channel B. In the complex output formats (decimate-by-4,
decimate-by-8, decimate-by-16), the samples are defined as AIn, AQn, BIn and BQn, where AIn and AQn are the
in-phase and quadrature-phase samples of channel A and BIn and BQn are the in-phase and quadrature-phase
samples of channel B. All samples are formatted as MSB first, LSB last.
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Table 21. JMODE 0 (12-bit, Decimate-by-1, Single-Channel, 8 Lanes)
OCTET
NIBBLE
0
0
1
1
2
2
3
4
3
5
6
4
7
8
5
9
10
6
11
12
7
13
14
15
DA0
S0
S8
S16
S24
S32
T
DA1
S2
S10
S18
S26
S34
T
DA2
S4
S12
S20
S28
S36
T
DA3
S6
S14
S22
S30
S38
T
DB0
S1
S9
S17
S25
S33
T
DB1
S3
S11
S19
S27
S35
T
DB2
S5
S13
S21
S29
S37
T
DB3
S7
S15
S23
S31
S39
T
Table 22. JMODE 1 (12-Bit, Decimate-by-1, Single-Channel, 16 Lanes)
OCTET
NIBBLE
0
0
1
1
2
2
3
4
3
5
6
4
7
8
5
9
10
6
11
12
7
13
14
15
DA0
S0
S16
S32
S48
S64
T
DA1
S2
S18
S34
S50
S66
T
DA2
S4
S20
S36
S52
S68
T
DA3
S6
S22
S38
S54
S70
T
DA4
S8
S24
S40
S56
S72
T
DA5
S10
S26
S42
S58
S74
T
DA6
S12
S28
S44
S60
S76
T
DA7
S14
S30
S46
S62
S78
T
DB0
S1
S17
S33
S49
S65
T
DB1
S3
S19
S35
S51
S67
T
DB2
S5
S21
S37
S53
S69
T
DB3
S7
S23
S39
S55
S71
T
DB4
S9
S25
S41
S57
S73
T
DB5
S11
S27
S43
S59
S75
T
DB6
S13
S29
S45
S61
S77
T
DB7
S15
S31
S47
S63
S79
T
Table 23. JMODE 2 (12-Bit, Decimate-by-1, Dual-Channel, 8 Lanes)
OCTET
NIBBLE
64
0
0
1
1
2
2
3
4
3
5
6
4
7
8
5
9
10
6
11
12
7
13
14
15
DA0
A0
A4
A8
A12
A16
T
DA1
A1
A5
A9
A13
A17
T
DA2
A2
A6
A10
A14
A18
T
DA3
A3
A7
A11
A15
A19
T
DB0
B0
B4
B8
B12
B16
T
DB1
B1
B5
B9
B13
B17
T
DB2
B2
B6
B10
B14
B18
T
DB3
B3
B7
B11
B15
B19
T
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Table 24. JMODE 3 (12-Bit, Decimate-by-1, Dual-Channel, 16 Lanes)
OCTET
NIBBLE
0
0
1
1
2
2
3
4
3
5
6
4
7
5
8
9
10
6
11
12
7
13
14
15
DA0
A0
A8
A16
A24
A32
T
DA1
A1
A9
A17
A25
A33
T
DA2
A2
A10
A18
A26
A34
T
DA3
A3
A11
A19
A27
A35
T
DA4
A4
A12
A20
A28
A36
T
DA5
A5
A13
A21
A29
A37
T
DA6
A6
A14
A22
A30
A38
T
DA7
A7
A15
A23
A31
A39
T
DB0
B0
B8
B16
B24
B32
T
DB1
B1
B9
B17
B25
B33
T
DB2
B2
B10
B18
B26
B34
T
DB3
B3
B11
B19
B27
B35
T
DB4
B4
B12
B20
B28
B36
T
DB5
B5
B13
B21
B29
B37
T
DB6
B6
B14
B22
B30
B38
T
DB7
B7
B15
B23
B31
B39
T
Table 25. JMODE 4 (8-Bit, Decimate-by-1, Single-Channel, 4 Lanes)
OCTET
NIBBLE
0
0
1
DA0
S0
DA1
S2
DB0
S1
DB1
S3
Table 26. JMODE 5 (8-Bit, Decimate-by-1, Single-Channel, 8 Lanes)
OCTET
NIBBLE
0
0
1
DA0
S0
DA1
S2
DA2
S4
DA3
S6
DB0
S1
DB1
S3
DB2
S5
DB3
S7
Table 27. JMODE 6 (8-Bit, Decimate-by-1, Dual-Channel, 4 Lanes)
OCTET
NIBBLE
0
0
1
DA0
A0
DA1
A1
DB0
B0
DB1
B1
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Table 28. JMODE 7 (8-Bit, Decimate-by-1, Dual-Channel, 8 Lanes)
OCTET
0
NIBBLE
0
1
DA0
A0
DA1
A1
DA2
A2
DA3
A3
DB0
B0
DB1
B1
DB2
B2
DB3
B3
Table 29. JMODE 9 (15-Bit, Decimate-by-2, Dual-Channel, 8 Lanes)
OCTET
NIBBLE
0
0
1
1
2
DA0
A0
DA1
A1
DA2
A2
DA3
A3
DB0
B0
DB1
B1
DB2
B2
DB3
B3
3
Table 30. JMODE 10 (15-Bit, Decimate-by-4, Dual-Channel, 4 Lanes)
OCTET
NIBBLE
0
0
1
1
2
DA0
AI0
DA1
AQ0
DB0
BI0
DB1
BQ0
3
Table 31. JMODE 11 (15-Bit, Decimate-by-4, Dual-Channel, 8 Lanes)
OCTET
NIBBLE
0
0
1
1
DA0
66
2
3
AI0
DA1
AI1
DA2
AQ0
DA3
AQ1
DB0
BI0
DB1
BI1
DB2
BQ0
DB3
BQ1
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Table 32. JMODE 12 (12-Bit, Decimate-by-4, Dual-Channel, 16 Lanes)
OCTET
0
NIBBLE
1
0
1
2
2
3
4
3
5
4
6
7
8
5
9
10
6
11
12
7
13
14
15
DA0
AI0
AI4
AI8
AI12
AI16
T
DA1
AQ0
AQ4
AQ8
AQ12
AQ16
T
DA2
AI1
AI5
AI9
AI13
AI17
T
DA3
AQ1
AQ5
AQ9
AQ13
AQ17
T
DA4
AI2
AI6
AI10
AI14
AI18
T
DA5
AQ2
AQ6
AQ10
AQ14
AQ218
T
DA6
AI3
AI7
AI11
AI15
AI19
T
DA7
AQ3
AQ7
AQ11
AQ15
AQ19
T
DB0
BI0
BI4
BI8
BI12
BI16
T
DB1
BQ0
BQ4
BQ8
BQ12
BQ16
T
DB2
BI1
BI5
BI9
BI13
BI17
T
DB3
BQ1
BQ5
BQ9
BQ13
BQ17
T
DB4
BI2
BI6
BI10
BI14
BI18
T
DB5
BQ2
BQ6
BQ10
BQ14
BQ218
T
DB6
BI3
BI7
BI11
BI15
BI19
T
DB7
BQ3
BQ7
BQ11
BQ15
BQ19
T
Table 33. JMODE 13 (15-Bit, Decimate-by-8, Dual-Channel, 2 Lanes)
OCTET
0
NIBBLE
0
1
1
2
2
3
3
4
5
6
DA0
AI0
AQ0
DB0
BI0
BQ0
7
Table 34. JMODE 14 (15-Bit, Decimate-by-8, Dual-Channel, 4 Lanes)
OCTET
0
NIBBLE
1
0
1
2
DA0
AI0
DA1
AQ0
DB0
BI0
DB1
BQ0
3
Table 35. JMODE 15 (15-Bit, Decimate-by-16, Dual-Channel, 1 Lane)
OCTET
0
NIBBLE
0
DA0
1
1
2
2
3
4
3
5
AI0
6
4
7
8
AQ0
5
9
10
6
11
12
7
13
BI0
14
15
BQ0
Table 36. JMODE 16 (15-Bit, Decimate-by-16, Dual-Channel, 2 Lanes)
OCTET
NIBBLE
0
0
1
1
2
2
3
4
3
5
6
DA0
AI0
AQ0
DB0
BI0
BQ0
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Table 37. JMODE 17 (8-bit, Decimate-by-1, Single-Channel, 16 lanes)
OCTET
0
NIBBLE
0
1
DA0
S0
DA1
S2
DA2
S4
DA3
S6
DA4
S8
DA5
S10
DA6
S12
DA7
S14
DB0
S1
DB1
S3
DB2
S5
DB3
S7
DB4
S9
DB5
S11
DB6
S13
DB7
S15
Table 38. JMODE 18 (8-Bit, Decimate-by-1, Dual-Channel, 16 Lanes)
OCTET
0
NIBBLE
0
1
DA0
A0
DA1
A1
DA2
A2
DA3
A3
DA4
A4
DA5
A5
DA6
A6
DA7
A7
DB0
B0
DB1
B1
DB2
B2
DB3
B3
DB4
B4
DB5
B5
DB6
B6
DB7
B7
7.4.3.2 Dual DDC and Redundant Data Mode
When operating in dual-channel mode, the data from one channel can be routed to both digital down-converter
blocks by using DIG_BIND_A or DIG_BIND_B (see the digital channel binding register). This feature enables
down-conversion of two separate captured bands from a single ADC channel. The second ADC can be powered
down in this mode by setting PD_ACH or PD_BCH (see the device configuration register).
Additionally, DIG_BIND_A or DIG_BIND_B can be used to provide redundant data to separate digital processors
by routing data from one ADC channel to both JESD204B links. Redundant data mode is available for all JMODE
modes except for the single-channel modes. Both dual DDC mode and redundant data mode are demonstrated
in Figure 83 where the data for ADC channel A is routed to both DDCs and then transmitted to a single
processor or two processors (for redundancy).
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DDC Bypass
DDC A
JESD204B
LINK A
(DA0-DA7)
MUX
MUX
ADC
Channel A
JMODE
DIG_BIND_A = 0
ADC
Channel B
DDC B
JESD204B
LINK B
(DB0-DB7)
MUX
MUX
DDC Bypass
JMODE
DIG_BIND_B = 0
.
Figure 83. Dual DDC Mode or Redundant Data Mode for Channel A
7.4.4 Power-Down Modes
The PD input pin allows the ADC12DJ2700 devices to be entirely powered down. Power-down can also be
controlled by MODE (see the device configuration register). The serial data output drivers are disabled when PD
is high. When the device returns to normal operation, the JESD204 link must be re-established, and the ADC
pipeline and decimation filters contain meaningless information so the system must wait a sufficient time for the
data to be flushed. If power-down for power savings is desired, the system must power down the supply voltages
regulators for VA19, VA11, and VD11 rather than make use of the PD input or MODE settings.
CAUTION
Powering down the high-speed data outputs (DA0± ... DA7±, DB0± ... DB7±) for
extended times may damage the output serializers, especially at high data rates.
Powering down the serializers occurs when the PD pin is held high, the MODE register
is programmed to a value other than 0x00 or 0x01, the PD_ACH or PD_BCH registers
settings are programmed to 1, or when the JMODE register setting is programmed to a
mode that uses less than the 16 total lanes that the device allows. For instance,
JMODE 0 uses eight total lanes and therefore the four highest-indexed lanes for each
JESD204B link (DA4± ... DA7±, DB4± ... DB7±) are powered down in this mode. When
the PD pin is held high or the MODE register is programmed to a value other than
0x00 or 0x01, all output serializers are powered down. When the PD_ACH or PD_BCH
register settings are programmed to 1, the associated ADC channel and lanes are
powered down. To prevent unreliable operation, the PD pin and MODE register must
only be used for brief periods of time to measure temperature diode offsets and not
used for long-term power savings. Furthermore, using a JMODE that uses fewer than
16 lanes results in unreliable operation of the unused lanes. If the system never uses
the unused lanes during the lifetime of the device, then the unused lanes do not cause
issues and can be powered down. If the system may make use of the unused lanes at
a later time, the reliable operation of the serializer outputs can be maintained by
enabling JEXTRA_A and JEXTRA_B, which results in the VD11 power consumption to
increase and the output serializers to toggle.
7.4.5 Test Modes
A number of device test modes are available. These modes insert known patterns of information into the device
data path for assistance with system debug, development, or characterization.
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7.4.5.1 Serializer Test-Mode Details
Test modes are enabled by setting JTEST (see the JESD204B test pattern control register) to the desired test
mode. Each test mode is described in detail in the following sections. Regardless of the test mode, the serializer
outputs are powered up based on JMODE. Only enable the test modes when the JESD204B link is disabled.
Figure 84 provides a diagram showing the various test mode insertion points.
ADC
JESD204B Block
JESD204B
TRANSPORT
LAYER
ADC
SCRAMBLER
(Optional)
Long/Short Transport
Octet Ramp
Test Mode Enable
JESD204B
LINK
LAYER
8b/10b
ENCODER
Repeated ILA
Modified RPAT
Test Mode Enable
JESD204B
TX
Active Lanes and
Serial Rates
Set by JMODE
PRBS
D21.5
K28.5
Serial Outputs High/Low
Test Mode Enable
Figure 84. Test Mode Insertion Points
7.4.5.2 PRBS Test Modes
The PRBS test modes bypass the 8b, 10b encoder. These test modes produce pseudo-random bit streams that
comply with the ITU-T O.150 specification. These bit streams are used with lab test equipment that can selfsynchronize to the bit pattern and, therefore, the initial phase of the pattern is not defined.
The sequences are defined by a recursive equation. For example, Equation 10 defines the PRBS7 sequence.
y[n] = y[n – 6]⊕y[n – 7]
where
•
bit n is the XOR of bit [n – 6] and bit [n – 7], which are previously transmitted bits
(10)
Table 39 lists equations and sequence lengths for the available PRBS test modes. The initial phase of the
pattern is unique for each lane.
Table 39. PBRS Mode Equations
PRBS TEST MODE
SEQUENCE
SEQUENCE LENGTH (bits)
PRBS7
y[n] = y[n – 6]⊕y[n – 7]
127
PRBS15
y[n] = y[n – 14]⊕y[n – 15]
32767
PRBS23
y[n] = y[n – 18]⊕y[n – 23]
8388607
7.4.5.3 Ramp Test Mode
In the ramp test mode, the JESD204B link layer operates normally, but the transport layer is disabled and the
input from the formatter is ignored. After the ILA sequence, each lane transmits an identical octet stream that
increments from 0x00 to 0xFF and repeats.
7.4.5.4 Short and Long Transport Test Mode
JESD204B defines both short and long transport test modes to verify that the transport layers in the transmitter
and receiver are operating correctly. The ADC12DJ2700 has three different transport layer test patterns
depending on the N' value of the specified JMODE (see Table 19).
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7.4.5.4.1 Short Transport Test Pattern
Short transport test patterns send a predefined octet format that repeats every frame. In the ADC12DJ2700, all
JMODE configurations that have an N' value of 8 or 12 use the short transport test pattern. Table 40 and
Table 41 define the short transport test patterns for N' values of 8 and 12. All applicable lanes are shown,
however only the enabled lanes (lowest indexed) for the configured JMODE are used.
Table 40. Short Transport Test Pattern for N' = 8 Modes (Length = 2 Frames)
FRAME
0
1
DA0
0x00
0xFF
DA1
0x01
0xFE
DA2
0x02
0xFD
DA3
0x03
0xFC
DB0
0x00
0xFF
DB1
0x01
0xFE
DB2
0x02
0xFD
DB3
0x03
0xFC
Table 41. Short Transport Test Pattern for N' = 12 Modes (Length = 1 Frame)
OCTET
NIBBLE
0
0
1
1
2
2
3
4
3
5
6
4
7
8
5
9
10
6
11
12
7
13
14
15
DA0
0xF01
0xF02
0xF03
0xF04
0xF05
T
DA1
0xE11
0xE12
0xE13
0xE14
0xE15
T
DA2
0xD21
0xD22
0xD23
0xD24
0xD25
T
DA3
0xC31
0xC32
0xC33
0xC34
0xC35
T
DA4
0xB41
0xB42
0xB43
0xB44
0xB45
T
DA5
0xA51
0xA52
0xA53
0xA54
0xA55
T
DA6
0x961
0x962
0x963
0x964
0x965
T
DA7
0x871
0x872
0x873
0x874
0x875
T
DB0
0xF01
0xF02
0xF03
0xF04
0xF05
T
DB1
0xE11
0xE12
0xE13
0xE14
0xE15
T
DB2
0xD21
0xD22
0xD23
0xD24
0xD25
T
DB3
0xC31
0xC32
0xC33
0xC34
0xC35
T
DB4
0xB41
0xB42
0xB43
0xB44
0xB45
T
DB5
0xA51
0xA52
0xA53
0xA54
0xA55
T
DB6
0x961
0x962
0x963
0x964
0x965
T
DB7
0x871
0x872
0x873
0x874
0x875
T
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7.4.5.4.2 Long Transport Test Pattern
The long-transport test mode is used in all of the JMODE modes where N' equals 16. Patterns are generated in
accordance with the JESD204B standard and are different for each output format as defined in Table 19. The
rules for the pattern are defined below. Equation 11 gives the length of the test pattern. The long transport test
pattern is the same for link A and link B, where DAx lanes belong to link A and DBx lanes belong to link B.
Long Test Pattern Length (Frames) = K × ceil[(M × S + 2) / K]
•
•
(11)
Sample Data:
– Frame 0: Each sample contains N bits, with all samples set to the converter ID (CID) plus 1 (CID + 1). The
CID is defined based on the converter number within the link; two links are used in all modes except
JMODE 15. Within a link, the converters are numbered by channel (A or B) and in-phase (I) and
quadrature-phase (Q) and reset between links. For instance, in JMODE 10, two links are used so channel
A and B data are separated into separate links and the in-phase component for each channel has CID = 0
and the quadrature-phase component has CID = 1. In JMODE 15, one link is used, so channel A and B
are within the same link and AI has CID = 0, AQ has CID = 1, BI has CID = 2, and BQ has CID = 3.
– Frame 1: Each sample contains N bits, with each sample (for each converter) set as its individual sample
ID (SID) within the frame plus 1 (SID + 1)
– Frame 2 +: Each sample contains N bits, with the data set to 2N–1 for all samples (for example, if N is 15
then 2N–1 = 16384)
Control Bits (if CS > 0):
– Frame 0 to M × S – 1: The control bit belonging to the sample mod (i, S) of the converter floor (i, S) is set
to 1 and all others are set to 0, where i is the frame index (i = 0 is the first frame of the pattern).
Essentially, the control bit walks from the lowest indexed sample to the highest indexed sample and from
the lowest indexed converter to the highest indexed converter, changing position every frame.
– Frame M × S +: All control bits are set to 0
Table 42 describes an example long transport test pattern for when JMODE = 10, K = 10.
Table 42. Example Long Transport Test Pattern (JMODE = 10, K = 10)
TIME →
OCTET
NUM
0
1
2
3
4
5
6
PATTERN REPEATS →
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
DA0
0x0003
0x0002
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x0003
DA1
0x0004
0x0003
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x0004
DB0
0x0003
0x0002
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x0003
DB1
0x0004
0x0003
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x8000
0x0004
Frame
n
Frame
n+1
Frame
n+2
Frame
n+3
Frame
n+4
Frame
n+5
Frame
n+6
Frame
n+7
Frame
n+8
Frame
n+9
Frame
n + 10
The pattern starts at the end of the initial lane alignment sequence (ILAS) and repeats indefinitely as long as the
link remains running. For more details see the JESD204B specification, section 5.1.6.3.
7.4.5.5 D21.5 Test Mode
In this test mode, the controller transmits a continuous stream of D21.5 characters (alternating 0s and 1s).
7.4.5.6 K28.5 Test Mode
In this test mode, the controller transmits a continuous stream of K28.5 characters.
7.4.5.7 Repeated ILA Test Mode
In this test mode, the JESD204B link layer operates normally, except that the ILA sequence (ILAS) repeats
indefinitely instead of starting the data phase. Whenever the receiver issues a synchronization request, the
transmitter initiates code group synchronization. Upon completion of code group synchronization, the transmitter
repeatedly transmits the ILA sequence.
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7.4.5.8 Modified RPAT Test Mode
A 12-octet repeating pattern is defined in INCITS TR-35-2004. The purpose of this pattern is to generate white
spectral content for JESD204B compliance and jitter testing. Table 43 lists the pattern before and after 8b, 10b
encoding.
Table 43. Modified RPAT Pattern Values
OCTET NUMBER
Dx.y NOTATION
8-BIT INPUT TO 8b, 10b ENCODER
0
D30.5
0xBE
1
D23.6
0xD7
2
D3.1
0x23
3
D7.2
0x47
4
D11.3
0x6B
5
D15.4
0x8F
6
D19.5
0xB3
7
D20.0
0x14
8
D30.2
0x5E
9
D27.7
0xFB
10
D21.1
0x35
11
D25.2
0x59
20b OUTPUT OF 8b, 10b ENCODER
(Two Characters)
0x86BA6
0xC6475
0xD0E8D
0xCA8B4
0x7949E
0xAA665
7.4.6 Calibration Modes and Trimming
The ADC12DJ2700 has two calibration modes available: foreground calibration and background calibration.
When foreground calibration is initiated the ADCs are automatically taken offline and the output data becomes
mid-code (0x000 in 2's complement) while a calibration is occurring. Background calibration allows the ADC to
continue normal operation while the ADC cores are calibrated in the background by swapping in a different ADC
core to take its place. Additional offset calibration features are available in both foreground and background
calibration modes. Further, a number of ADC parameters can be trimmed to optimize performance in a user
system.
The ADC12DJ2700 consists of a total of six sub-ADCs, each referred to as a bank, with two banks forming an
ADC core. The banks sample out-of-phase so that each ADC core is two-way interleaved. The six banks form
three ADC cores, referred to as ADC A, ADC B, and ADC C. In foreground calibration mode, ADC A samples
INA± and ADC B samples INB± in dual-channel mode and both ADC A and ADC B sample INA± (or INB±) in
single-channel mode. In the background calibration modes, the third ADC core, ADC C, is swapped in
periodically for ADC A and ADC B so that they can be calibrated without disrupting operation. Figure 85 provides
a diagram of the calibration system including labeling of the banks that make up each ADC core. When
calibration is performed the linearity, gain, and offset voltage for each bank are calibrated to an internally
generated calibration signal. The analog inputs can be driven during calibration, both foreground and
background, except that when offset calibration (OS_CAL or BGOS_CAL) is used there must be no signals (or
aliased signals) near DC for proper estimation of the offset (see the Offset Calibration section).
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ADC A
Interleave
Bank 0
MUX
INA+
Calibration
Signal
INA±
Bank 1
Calibration
Engine
MUX
ADC A
Output
ADC C
Interleave
Bank 2
MUX
Calibration
Signal
Calibration
Engine
Bank 3
Calibration
Engine
INB+
ADC B
MUX
ADC B
Output
Interleave
Bank 4
INB±
MUX
Calibration
Signal
Calibration
Engine
Bank 5
Calibration
Engine
Figure 85. ADC12DJ2700 Calibration System Block Diagram
In addition to calibration, a number of ADC parameters are user controllable to provide trimming for optimal
performance. These parameters include input offset voltage, ADC gain, interleaving timing, and input termination
resistance. The default trim values are programmed at the factory to unique values for each device that are
determined to be optimal at the test system operating conditions. The user can read the factory-programmed
values from the trim registers and adjust as desired. The register fields that control the trimming are labeled
according to the input that is being sampled (INA± or INB±), the bank that is being trimmed, or the ADC core that
is being trimmed. The user is not expected to change the trim values as operating conditions change, however
optimal performance can be obtained by doing so. Any custom trimming must be done on a per device basis
because of process variations, meaning that there is no global optimal setting for all parts. See the Trimming
section for information about the available trim parameters and associated registers.
7.4.6.1 Foreground Calibration Mode
Foreground calibration requires the ADC to stop converting the analog input signals during the procedure.
Foreground calibration always runs on power-up and the user must wait a sufficient time before programming the
device to ensure that the calibration is finished. Foreground calibration can be initiated by triggering the
calibration engine. The trigger source can be either the CAL_TRIG pin or CAL_SOFT_TRIG (see the calibration
software trigger register) and is chosen by setting CAL_TRIG_EN (see the calibration pin configuration register).
7.4.6.2 Background Calibration Mode
Background calibration mode allows the ADC to continuously operate, with no interruption of data. This
continuous operation is accomplished by activating an extra ADC core that is calibrated and then takes over
operation for one of the other previously active ADC cores. When that ADC core is taken off-line, that ADC is
calibrated and can in turn take over to allow the next ADC to be calibrated. This process operates continuously,
ensuring the ADC cores always provide the optimum performance regardless of system operating condition
changes. Because of the additional active ADC core, background calibration mode has increased power
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consumption in comparison to foreground calibration mode. The low-power background calibration (LPBG) mode
discussed in the Low-Power Background Calibration (LPBG) Mode section provides reduced average power
consumption in comparison with the standard background calibration mode. Background calibration can be
enabled by setting CAL_BG (see the calibration configuration 0 register). CAL_TRIG_EN must be set to 0 and
CAL_SOFT_TRIG must be set to 1.
Great care has been taken to minimize effects on converted data as the core switching process occurs, however,
small brief glitches may still occur on the converter data as the cores are swapped. See the Typical
Characteristics section for examples of possible glitches in sine-wave and DC signals.
7.4.6.3 Low-Power Background Calibration (LPBG) Mode
Low-power background calibration (LPBG) mode reduces the power-overhead of enabling the additional ADC
core while still allowing background calibration of the ADC cores to maintain optimal performance as operating
conditions change. LPBG calibration modifies the background calibration procedure by powering down the spare
ADC core until it is ready to be calibrated. Set LP_EN = 1 to enable the low-power background calibration
feature. Calibration and swapping of ADC cores can be controlled either automatically by the device or manually
by the system by setting LP_TRIG appropriately. Manual control (LP_TRIG=1) allows the system to trigger
calibration in order to limit the number of calibration cycles that occur to avoid unnecessary core swaps or to
keep power consumption at a minimum. For instance, the user may decide to run calibration only when the
system temperature changes by some fixed temperature. If manual control is not necessary the automatic
calibration control can be enabled (LP_TRIG=0) to calibrate at fixed time intervals.
In automatic calibration mode (LP_TRIG=0) the spare ADC core sleep time can be controlled by the
LP_SLEEP_DLY register setting. LP_SLEEP_DLY is used to adjust the amount of time an ADC sleeps before
waking up for calibration (when LP_EN=1 and LP_TRIG = 0). LP_WAKE_DLY sets how long the core is allowed
to stabilize after being awoken before calibration begins. In automatic calibration control mode the freshly
calibrated core is swapped in for an active core as soon as calibration finishes and the new spare core is
powered down for the sleep duration before waking up and calibrating.
Manual calibration control is enabled by setting LP_TRIG high in order to use the calibration trigger
(CAL_SOFT_TRIG or CALTRIG) to trigger calibrations and core swaps. When manual control is enabled
(LP_TRIG=1) the spare ADC is held in sleep mode while the calibration trigger is high. Setting the calibration
trigger low then wakes up the spare ADC core and starts the calibration routine after waiting for the specified
wake delay (LP_WAKE_DLY). The spare ADC core is swapped in for an active core once calibration is complete
and the calibration trigger is set high again. If the calibration trigger is held low, then the spare ADC core
calibrates and remains powered until the calibration trigger goes high; therefore consuming power. can report
when the spare ADC finishes calibration on the CALSTAT output pin by setting the CALSTAT pin to output the
CAL_STOPPED signal (CAL_STATUS_SEL = 1). For lowest power consumption, set the calibration trigger high
before calibration finishes to allow the spare ADC to swap in for an active ADC core as soon as calibration
finishes. Otherwise, the ADC core swap can be timed manually by setting the calibration trigger high at the
desired time to minimize system impact of potential glitches caused by the swapping procedure.
In LPBG mode there is an increase in power consumption during the ADC core calibration. The longer the spare
ADC is held asleep the lower the average power consumption, however large shifts in operating conditions
during the sleep cycle may cause degraded ADC performance due to non-optimized calibration data for the
active ADC core. The power consumption roughly alternates between the power consumption in foreground
calibration when the spare ADC core is sleeping to the power consumption in background calibration when the
spare ADC is being calibrated. Design the power-supply network to handle the transient power requirements for
this mode, including bulk capacitance after any power supply filtering network to help regulate the supply voltage
during the supply transient.
7.4.7 Offset Calibration
Foreground calibration and background calibration modes inherently calibrate the offsets of the ADC cores;
however, the input buffers sit outside of the calibration loop and therefore their offsets are not calibrated by the
standard calibration process. In both dual-channel mode and single-channel mode, uncalibrated input buffer
offsets result in a shift in the mid-code output (DC offset) with no input. Further, in single-channel mode
uncalibrated input buffer offsets can result in a fixed spur at fS / 2. A separate calibration is provided to correct
the input buffer offsets.
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There must be no signals at or near DC or aliased signals that fall at or near DC in order to properly calibration
the offsets, requiring the system to ensure this condition during normal operation or have the ability to mute the
input signal during calibration. Foreground offset calibration is enabled via CAL_OS and only performs the
calibration one time as part of the foreground calibration procedure. Background offset calibration is enabled via
CAL_BGOS and continues to correct the offset as part of the background calibration routine to account for
operating condition changes. When CAL_BGOS is set, the system must ensure that there are no DC or near DC
signals or aliased signals that fall at or near DC during normal operation. Offset calibration can be performed as
a foreground operation when using background calibration by setting CAL_OS to 1 before setting CAL_EN, but
does not correct for variations as operating conditions change.
The offset calibration correction uses the input offset voltage trim registers (see Table 44) to correct the offset
and therefore must not be written by the user when offset calibration is used. The user can read the calibrated
values by reading the OADJ_x_VINy registers, where x is the ADC core and y is the input (INA± or INB±), after
calibration is completed. Only read the values when FG_DONE is read as 1 when using foreground offset
calibration (CAL_OS = 1) and do not read the values when using background offset calibration (CAL_BGOS = 1).
Setting CAL_OS to 1 and CAL_BG to 1 performs an offset calibration of all three ADC cores during the
foreground calibration process.
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7.4.8 Trimming
Table 44 lists the parameters that can be trimmed and the associated registers. User trimming is limited to
foreground (FG) calibration only.
Table 44. Trim Register Descriptions
TRIM PARAMETER
Band-gap reference
Input termination resistance
Input offset voltage
INA± and INB± gain
INA± and INB± full-scale input voltage
Intra-ADC core timing (bank timing)
Inter-ADC core timing (dual-channel mode)
Inter-ADC core timing (single-channel mode)
TRIM REGISTER
BG_TRIM
NOTES
Measurement on BG output pin.
RTRIM_x,
where x = A for INA± or B for INB±)
The device must be powered on with a clock
applied.
OADJ_x_VINy,
where x = ADC core (A or B)
and y = A for INA± or B for INB±)
Input offset adjustment in dual channel mode
consists of changing OADJ_A_VINA for
channel A and OADJ_B_VINB for channel B.
In single channel mode, OADJ_A_VINx and
OADJ_B_VINx must be adjusted together to
trim the input offset or adjusted separate to
compensate the fS/2 offset spur.
GAIN_TRIM_x,
where x = A for INA± or B for INB±)
Set FS_RANGE_A and FS_RANGE_B to
default values before trimming the input. Use
FS_RANGE_A and FS_RANGE_B to adjust
the full-scale input voltage. To trim the gain
of ADC core A, change GAIN_B0 and
GAIN_B1 together in the same direction. To
trim the gain of ADC core B, change
GAIN_B4 and GAIN_B5 together in the same
direction. To trim the gain of the two banks
within ADC A, change GAIN_B0 and
GAIN_B1 in opposite directions. To trim the
gain of the two banks within ADC B, change
GAIN_B4 and GAIN_B5 in opposite
directions.
FS_RANGE_x,
where x = A for INA± or B for INB±)
Full-scale input voltage adjustment for each
input. The default value is effected by
GAIN_TRIM_x (x = A or B). Trim
GAIN_TRIM_x with FS_RANGE_x set to the
default value. FS_RANGE_x can then be
used to trim the full-scale input voltage.
Bx_TIME_y,
where x = bank number (0, 1, 4 or 5)
and y = 0° or –90° clock phase
Trims the timing between the two banks of
an ADC core (ADC A or B). The 0° clock
phase is used for dual channel mode and for
ADC B in single channel mode. The –90°
clock phase is used only for ADC A in singlechannel mode. A mismatch in the timing
between the two banks of an ADC core can
result in an fS/2-fIN spur in dual channel
mode or fS/4±fIN spurs in single channel
mode.
TADJ_A, TADJ_B
The suffix letter (A or B) indicates the ADC
core that is being trimmed. Changing either
TADJ_A or TADJ_B adjusts the sampling
instance of ADC A relative to ADC B in dual
channel mode.
TADJ_A_FG90, TADJ_B_FG0
These trim registers are used to adjust the
timing of ADC core A relative to ADC core B
in single channel mode. A mismatch in the
timing results in an fS/2-fIN spur that is signal
dependent. Changing either TADJ_A_FG90
or TADJ_B_FG0 changes the relative timing
of ADC core A relative to ADC core B in
single channel mode. These registers are
trimmed at production to optimize
performance for INA±.
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7.4.9 Offset Filtering
The ADC12DJ2700 has an additional feature that can be enabled to reduce offset-related interleaving spurs at fS
/ 2 and fS / 4 (single input mode only). Offset filtering is enabled via CAL_OSFILT. The OSFILT_BW and
OSFILT_SOAK parameters can be adjusted to tradeoff offset spur reduction with potential impact on information
in the mission mode signal being processed. Set these two parameters to the same value under most situations.
The DC_RESTORE setting is used to either retain or filter out all DC-related content in the signal. This feature
implements a notch filter at fS / 2 and fS / 4 (single input mode only) and also filters out signals that fall at these
frequency locations. Reducing the notch filter bandwidth using OSFILT_BW can reduce the range of signals that
are filtered by this feature.
78
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7.5 Programming
7.5.1 Using the Serial Interface
The serial interface is accessed using the following four pins: serial clock (SCLK), serial data in (SDI), serial data
out (SDO), and serial interface chip-select (SCS). Register access is enabled through the SCS pin.
7.5.1.1 SCS
This signal must be asserted low to access a register through the serial interface. Setup and hold times with
respect to the SCLK must be observed.
7.5.1.2 SCLK
Serial data input is accepted at the rising edge of this signal. SCLK has no minimum frequency requirement.
7.5.1.3 SDI
Each register access requires a specific 24-bit pattern at this input. This pattern consists of a read-and-write
(R/W) bit, register address, and register value. The data are shifted in MSB first and multi-byte registers are
always in little-endian format (least significant byte stored at the lowest address). Setup and hold times with
respect to the SCLK must be observed (see the Timing Requirements table).
7.5.1.4 SDO
The SDO signal provides the output data requested by a read command. This output is high impedance during
write bus cycles and during the read bit and register address portion of read bus cycles.
As shown in Figure 86, each register access consists of 24 bits. The first bit is high for a read and low for a write.
The next 15 bits are the address of the register that is to be written to. During write operations, the last eight bits
are the data written to the addressed register. During read operations, the last eight bits on SDI are ignored and,
during this time, the SDO outputs the data from the addressed register. Figure 86 shows the serial protocol
details.
Single Register Access
SCS
1
8
16
17
24
SCLK
Command Field
SDI
R/W
A14
A13 A12
A11
A10
A9
A8
A7
A6
Data Field
A5
A4
A3
A2
A1
A0
D7
D6
D5
D4
D3
D2
D1
D0
Data Field
SDO
(read mode)
High Z
D7
D6
D5
D4
D3
D2
D1
D0
High Z
Figure 86. Serial Interface Protocol: Single Read/Write
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Programming (continued)
7.5.1.5 Streaming Mode
The serial interface supports streaming reads and writes. In this mode, the initial 24 bits of the transaction
specifics the access type, register address, and data value as normal. Additional clock cycles of write or read
data are immediately transferred, as long as the SCS input is maintained in the asserted (logic low) state. The
register address auto increments (default) or decrements for each subsequent 8-bit transfer of the streaming
transaction. The ADDR_ASC bit (register 000h, bits 5 and 2) controls whether the address value ascends
(increments) or descends (decrements). Streaming mode can be disabled by setting the ADDR_HOLD bit (see
the user SPI configuration register). Figure 87 shows the streaming mode transaction details.
Multiple Register Access
SCS
8
1
16
17
24
25
32
SCLK
Command Field
SDI
R/W A14
A13
A12
A1
1
A10
A9
A8
A7
Data Field (write mode)
Data Field (write mode)
A6
A5
A4
A3
A2
A1
A0
D7
D6
D5
D4
D3
D2
D1
D0
D7
D6
D5
D4
D3
D7
D6
D5
D4
D3
D2
D1
D0
Data Field
Data Field
High Z
SDO
(read mode)
D2
D1
D0
D7
D6
D5
D4
D3
D2
D1
D0
High Z
Figure 87. Serial Interface Protocol: Streaming Read/Write
See the Register Maps section for detailed information regarding the registers.
NOTE
The serial interface must not be accessed during ADC calibration. Accessing the serial
interface during this time impairs the performance of the device until the device is
calibrated correctly. Writing or reading the serial registers also reduces dynamic ADC
performance for the duration of the register access time.
7.6 Register Maps
The Memory Map lists all the ADC12DJ2700 registers.
Memory Map
ADDRESS
RESET
ACRONYM
TYPE
REGISTER NAME
STANDARD SPI-3.0 (0x000 to 0x00F)
0x000
0x30
CONFIG_A
R/W
0x001
Undefined
RESERVED
R
Configuration A Register
0x002
0x00
DEVICE_CONFIG
R/W
0x003
0x03
CHIP_TYPE
R
Chip Type Register
0x004-0x005
0x0020
CHIP_ID
R
Chip ID Registers
0x006
0x0A
CHIP_VERSION
R
Chip Version Register
RESERVED
Device Configuration Register
0x007-0x00B
Undefined
RESERVED
R
RESERVED
0x00C-0x00D
0x0451
VENDOR_ID
R
Vendor Identification Register
0x00E-0x00F
Undefined
RESERVED
R
RESERVED
USER SPI CONFIGURATION (0x010 to 0x01F)
0x010
0x00
USR0
R/W
0x011-0x01F
Undefined
RESERVED
R
80
User SPI Configuration Register
RESERVED
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Register Maps (continued)
Memory Map (continued)
ADDRESS
RESET
ACRONYM
TYPE
REGISTER NAME
MISCELLANEOUS ANALOG REGISTERS (0x020 to 0x047)
0x020-0x028
Undefined
RESERVED
R
0x029
0x00
CLK_CTRL0
R/W
RESERVED
Clock Control Register 0
0x02A
0x20
CLK_CTRL1
R/W
Clock Control Register 1
0x02B
Undefined
RESERVED
R
RESERVED
0x02C-0x02E
Undefined
SYSREF_POS
R
SYSREF Capture Position Register
0x02F
Undefined
RESERVED
R
RESERVED
0x030-0x031
0xA000
FS_RANGE_A
R/W
INA Full-Scale Range Adjust Register
0x032-0x033
0xA000
FS_RANGE_B
R/W
INB Full-Scale Range Adjust Register
0x034-0x037
Undefined
RESERVED
R
0x038
0x00
BG_BYPASS
R/W
0x039-0x03A
Undefined
RESERVED
R
0x03B
0x00
TMSTP_CTRL
R/W
0x03C-0x047
Undefined
RESERVED
R
RESERVED
Internal Reference Bypass Register
RESERVED
TMSTP± Control Register
RESERVED
SERIALIZER REGISTERS (0x048 to 0x05F)
0x048
0x00
SER_PE
R/W
0x049-0x05F
Undefined
RESERVED
R
Serializer Pre-Emphasis Control Register
RESERVED
CALIBRATION REGISTERS (0x060 to 0x0FF)
0x060
0x01
INPUT_MUX
R/W
Input Mux Control Register
0x061
0x01
CAL_EN
R/W
Calibration Enable Register
0x062
0x01
CAL_CFG0
R/W
Calibration Configuration 0 Register
0x063-0x069
Undefined
RESERVED
R
RESERVED
0x06A
Undefined
CAL_STATUS
R
Calibration Status Register
0x06B
0x00
CAL_PIN_CFG
R/W
Calibration Pin Configuration Register
0x06C
0x01
CAL_SOFT_TRIG
R/W
Calibration Software Trigger Register
0x06D
Undefined
RESERVED
R
0x06E
0x88
CAL_LP
R/W
0x06F
Undefined
RESERVED
R
0x070
0x00
CAL_DATA_EN
R/W
Calibration Data Enable Register
0x071
Undefined
CAL_DATA
R/W
Calibration Data Register
0x072-0x079
Undefined
RESERVED
R
0x07A
Undefined
GAIN_TRIM_A
R/W
Channel A Gain Trim Register
0x07B
Undefined
GAIN_TRIM_B
R/W
Channel B Gain Trim Register
0x07C
Undefined
BG_TRIM
R/W
Band-Gap Reference Trim Register
0x07D
Undefined
RESERVED
R
0x07E
Undefined
RTRIM_A
R/W
VINA Input Resistor Trim Register
0x07F
Undefined
RTRIM_B
R/W
VINB Input Resistor Trim Register
0x080
Undefined
TADJ_A_FG90
R/W
Timing Adjustment for A-ADC, Single-Channel Mode,
Foreground Calibration Register
0x081
Undefined
TADJ_B_FG0
R/W
Timing Adjustment for B-ADC, Single-Channel Mode,
Foreground Calibration Register
0x082
Undefined
TADJ_A_BG90
R/W
Timing Adjustment for A-ADC, Single-Channel Mode,
Background Calibration Register
0x083
Undefined
TADJ_C_BG0
R/W
Timing Adjustment for C-ADC, Single-Channel Mode,
Background Calibration Register
0x084
Undefined
TADJ_C_BG90
R/W
Timing Adjustment for C-ADC, Single-Channel Mode,
Background Calibration Register
RESERVED
Low-Power Background Calibration Register
RESERVED
RESERVED
RESERVED
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Register Maps (continued)
Memory Map (continued)
ADDRESS
RESET
ACRONYM
TYPE
REGISTER NAME
0x085
Undefined
TADJ_B_BG0
R/W
Timing Adjustment for B-ADC, Single-Channel Mode,
Background Calibration Register
0x086
Undefined
TADJ_A
R/W
Timing Adjustment for A-ADC, Dual-Channel Mode Register
0x087
Undefined
TADJ_CA
R/W
Timing Adjustment for C-ADC Acting for A-ADC, DualChannel Mode Register
0x088
Undefined
TADJ_CB
R/W
Timing Adjustment for C-ADC Acting for B-ADC, DualChannel Mode Register
0x089
Undefined
TADJ_B
R/W
Timing Adjustment for B-ADC, Dual-Channel Mode Register
0x08A-0x08B
Undefined
OADJ_A_INA
R/W
Offset Adjustment for A-ADC and INA Register
0x08C-0x08D
Undefined
OADJ_A_INB
R/W
Offset Adjustment for A-ADC and INB Register
0x08E-0x08F
Undefined
OADJ_C_INA
R/W
Offset Adjustment for C-ADC and INA Register
0x090-0x091
Undefined
OADJ_C_INB
R/W
Offset Adjustment for C-ADC and INB Register
0x092-0x093
Undefined
OADJ_B_INA
R/W
Offset Adjustment for B-ADC and INA Register
0x094-0x095
Undefined
OADJ_B_INB
R/W
Offset Adjustment for B-ADC and INB Register
0x096
Undefined
RESERVED
R
0x097
0x00
OSFILT0
R/W
Offset Filtering Control 0
0x098
0x33
OSFILT1
R/W
Offset Filtering Control 1
0x099-0x0FF
Undefined
RESERVED
R
RESERVED
RESERVED
RESERVED
ADC BANK REGISTERS (0x100 to 0x15F)
0x100-0x101
Undefined
RESERVED
R
0x102
Undefined
B0_TIME_0
R/W
Timing Adjustment for Bank 0 (0° Clock) Register
0x103
Undefined
B0_TIME_90
R/W
Timing Adjustment for Bank 0 (–90° Clock) Register
0x104-0x111
Undefined
RESERVED
R
0x112
Undefined
B1_TIME_0
R/W
Timing Adjustment for Bank 1 (0° Clock) Register
0x113
Undefined
B1_TIME_90
R/W
Timing Adjustment for Bank 1 (–90° Clock) Register
0x114-0x121
Undefined
RESERVED
R
0x122
Undefined
B2_TIME_0
R/W
Timing Adjustment for Bank 2 (0° Clock) Register
0x123
Undefined
B2_TIME_90
R/W
Timing Adjustment for Bank 2 (–90° Clock) Register
0x124-0x131
Undefined
RESERVED
R
0x132
Undefined
B3_TIME_0
R/W
Timing Adjustment for Bank 3 (0° Clock) Register
0x133
Undefined
B3_TIME_90
R/W
Timing Adjustment for Bank 3 (–90° Clock) Register
0x134-0x141
Undefined
RESERVED
R
0x142
Undefined
B4_TIME_0
R/W
Timing Adjustment for Bank 4 (0° Clock) Register
0x143
Undefined
B4_TIME_90
R/W
Timing Adjustment for Bank 4 (–90° Clock) Register
0x144-0x151
Undefined
RESERVED
R
0x152
Undefined
B5_TIME_0
R/W
Timing Adjustment for Bank 5 (0° Clock) Register
0x153
Undefined
B5_TIME_90
R/W
Timing Adjustment for Bank 5 (–90° Clock) Register
0x154-0x15F
Undefined
RESERVED
R
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
LSB CONTROL REGISTERS (0x160 to 0x1FF)
0x160
0x00
ENC_LSB
R/W
0x161-0x1FF
Undefined
RESERVED
R
LSB Control Bit Output Register
RESERVED
JESD204B REGISTERS (0x200 to 0x20F)
82
0x200
0x01
JESD_EN
R/W
JESD204B Enable Register
0x201
0x02
JMODE
R/W
JESD204B Mode (JMODE) Register
0x202
0x1F
KM1
R/W
JESD204B K Parameter Register
0x203
0x01
JSYNC_N
R/W
JESD204B Manual SYNC Request Register
0x204
0x02
JCTRL
R/W
JESD204B Control Register
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Register Maps (continued)
Memory Map (continued)
ADDRESS
RESET
ACRONYM
TYPE
0x205
0x00
JTEST
R/W
JESD204B Test Pattern Control Register
REGISTER NAME
0x206
0x00
DID
R/W
JESD204B DID Parameter Register
0x207
0x00
FCHAR
R/W
JESD204B Frame Character Register
0x208
Undefined
JESD_STATUS
R/W
JESD204B, System Status Register
0x209
0x00
PD_CH
R/W
JESD204B Channel Power-Down
0x20A
0x00
JEXTRA_A
R/W
JESD204B Extra Lane Enable (Link A)
0x20B
0x00
JEXTRA_B
R/W
JESD204B Extra Lane Enable (Link B)
0x20C-0x20F
Undefined
RESERVED
R
RESERVED
DIGITAL DOWN CONVERTER REGISTERS (0x210-0x2AF)
0x210
0x00
DDC_CFG
R/W
DDC Configuration Register
0x211
0xF2
OVR_T0
R/W
Overrange Threshold 0 Register
0x212
0xAB
OVR_T1
R/W
Overrange Threshold 1 Register
0x213
0x07
OVR_CFG
R/W
Overrange Configuration Register
0x214
0x00
CMODE
R/W
DDC Configuration Preset Mode Register
0x215
0x00
CSEL
R/W
DDC Configuration Preset Select Register
0x216
0x02
DIG_BIND
R/W
Digital Channel Binding Register
0x217-0x218
0x0000
NCO_RDIV
R/W
Rational NCO Reference Divisor Register
0x219
0x02
NCO_SYNC
R/W
NCO Synchronization Register
0x21A-0x21F
Undefined
RESERVED
R
0x220-0x223
0xC0000000
FREQA0
R/W
NCO Frequency (DDC A Preset 0)
0x224-0x225
0x0000
PHASEA0
R/W
NCO Phase (DDC A Preset 0)
RESERVED
0x226-0x227
Undefined
RESERVED
R
0x228-0x22B
0xC0000000
FREQA1
R/W
RESERVED
NCO Frequency (DDC A Preset 1)
0x22C-0x22D
0x0000
PHASEA1
R/W
NCO Phase (DDC A Preset 1)
0x22E-0x22F
Undefined
RESERVED
R
0x230-0x233
0xC0000000
FREQA2
R/W
NCO Frequency (DDC A Preset 2)
0x234-0x235
0x0000
PHASEA2
R/W
NCO Phase (DDC A Preset 2)
0x236-0x237
Undefined
RESERVED
R
RESERVED
RESERVED
0x238-0x23B
0xC0000000
FREQA3
R/W
NCO Frequency (DDC A Preset 3)
0x23C-0x23D
0x0000
PHASEA3
R/W
NCO Phase (DDC A Preset 3)
0x23E-0x23F
Undefined
RESERVED
R
0x240-0x243
0xC0000000
FREQB0
R/W
NCO Frequency (DDC B Preset 0)
0x244-0x245
0x0000
PHASEB0
R/W
NCO Phase (DDC B Preset 0)
0x246-0x247
Undefined
RESERVED
R
0x248-0x24B
0xC0000000
FREQB1
R/W
NCO Frequency (DDC B Preset 1)
NCO Phase (DDC B Preset 1)
RESERVED
RESERVED
0x24C-0x24D
0x0000
PHASEB1
R/W
0x24E-0x24F
Undefined
RESERVED
R
0x250-0x253
0xC0000000
FREQB2
R/W
NCO Frequency (DDC B Preset 2)
NCO Phase (DDC B Preset 2)
RESERVED
0x254-0x255
0x0000
PHASEB2
R/W
0x256-0x257
Undefined
RESERVED
R
0x258-0x25B
0xC0000000
FREQB3
R/W
NCO Frequency (DDC B Preset 3)
NCO Phase (DDC B Preset 3)
RESERVED
0x25C-0x25D
0x0000
PHASEB3
R/W
0x25E-0x296
Undefined
RESERVED
R
RESERVED
0x297
Undefined
SPIN_ID
R
Spin Identification Value
0x298-0x2AF
Undefined
RESERVED
R
RESERVED
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Register Maps (continued)
Memory Map (continued)
ADDRESS
RESET
ACRONYM
TYPE
REGISTER NAME
SYSREF CALIBRATION REGISTERS (0x2B0 to 0x2BF)
0x2B0
0x00
SRC_EN
R/W
SYSREF Calibration Enable Register
0x2B1
0x05
SRC_CFG
R/W
SYSREF Calibration Configuration Register
0x2B2-0x2B4
Undefined
SRC_STATUS
R
0x2B5-0x2B7
0x00
TAD
R/W
DEVCLK Aperture Delay Adjustment Register
DEVCLK Timing Adjust Ramp Control Register
SYSREF Calibration Status
0x2B8
0x00
TAD_RAMP
R/W
0x2B9-0x2BF
Undefined
RESERVED
R
RESERVED
Alarm Interrupt Status Register
ALARM REGISTERS (0x2C0 to 0x2C2)
84
0x2C0
Undefined
ALARM
R
0x2C1
0x1F
ALM_STATUS
R/W
Alarm Status Register
0x2C2
0x1F
ALM_MASK
R/W
Alarm Mask Register
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7.6.1 Register Descriptions
Table 45 lists the access codes for the ADC12DJ2700 registers.
Table 45. ADC12DJ2700 Access Type Codes
Access Type
Code
Description
R
R
Read
R-W
R/W
Read or write
W
W
Write
-n
Value after reset or the default
value
7.6.1.1 Standard SPI-3.0 (0x000 to 0x00F)
Table 46. Standard SPI-3.0 Registers
ADDRESS
RESET
ACRONYM
0x000
0x30
CONFIG_A
Configuration A Register
REGISTER NAME
0x001
Undefined
RESERVED
RESERVED
0x002
0x00
—
DEVICE_CONFIG Device Configuration Register
0x003
0x03
CHIP_TYPE
0x004-0x005
0x0020
CHIP_ID
SECTION
Configuration A Register (address = 0x000) [reset = 0x30]
Device Configuration Register (address = 0x002) [reset =
0x00]
Chip Type Register
Chip Type Register (address = 0x003) [reset = 0x03]
Chip ID Registers
Chip ID Register (address = 0x004 to 0x005) [reset =
0x0020]
0x006
0x0A
CHIP_VERSION
0x007-0x00B
Undefined
RESERVED
Chip Version Register
RESERVED
Chip Version Register (address = 0x006) [reset = 0x01]
0x00C-0x00D
0x0451
VENDOR_ID
Vendor Identification Register
0x00E-0x00F
Undefined
RESERVED
RESERVED
—
Vendor Identification Register (address = 0x00C to
0x00D) [reset = 0x0451]
—
7.6.1.1.1 Configuration A Register (address = 0x000) [reset = 0x30]
Figure 88. Configuration A Register (CONFIG_A)
7
SOFT_RESET
R/W-0
6
RESERVED
R-0
5
ADDR_ASC
R/W-1
4
SDO_ACTIVE
R-1
3
2
1
0
RESERVED
R-0000
Table 47. CONFIG_A Field Descriptions
Bit
Field
Type
Reset
Description
7
SOFT_RESET
R/W
0
Setting this bit results in a full reset of the device. This bit is selfclearing. After writing this bit, the device may take up to 750 ns
to reset. During this time, do not perform any SPI transactions.
6
RESERVED
R
0
RESERVED
5
ADDR_ASC
R/W
1
0: Descend – decrement address while streaming reads/writes
1: Ascend – increment address while streaming reads/writes
(default)
4
SDO_ACTIVE
R
1
Always returns 1, indicating that the device always uses 4-wire
SPI mode.
RESERVED
R
0000
RESERVED
3-0
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7.6.1.1.2 Device Configuration Register (address = 0x002) [reset = 0x00]
Figure 89. Device Configuration Register (DEVICE_CONFIG)
7
6
5
4
3
2
1
RESERVED
R-0000 00
0
MODE
R/W-00
Table 48. DEVICE_CONFIG Field Descriptions
Bit
Field
Type
Reset
Description
7-2
RESERVED
R
0000 00
RESERVED
1-0
MODE
R/W
00
The SPI 3.0 specification lists 1 as the low-power functional
mode, 2 as the low-power fast resume, and 3 as power-down.
This device does not support these modes.
0: Normal operation – full power and full performance (default)
1: Normal operation – full power and full performance
2: Power down - everything is powered down. Only use this
setting for brief periods of time to calibrate the on-chip
temperature diode measurement. See the Recommended
Operating Conditions table for more information.
3: Power down - everything is powered down. Only use this
setting for brief periods of time to calibrate the on-chip
temperature diode measurement. See the Recommended
Operating Conditions table for more information.
7.6.1.1.3 Chip Type Register (address = 0x003) [reset = 0x03]
Figure 90. Chip Type Register (CHIP_TYPE)
7
6
5
4
3
2
RESERVED
R-0000
1
0
CHIP_TYPE
R-0011
Table 49. CHIP_TYPE Field Descriptions
Bit
Field
Type
Reset
Description
7-4
RESERVED
R
0000
RESERVED
3-0
CHIP_TYPE
R
0011
Always returns 0x3, indicating that the device is a high-speed
ADC.
7.6.1.1.4 Chip ID Register (address = 0x004 to 0x005) [reset = 0x0020]
Figure 91. Chip ID Register (CHIP_ID)
15
14
13
12
11
10
9
8
3
2
1
0
CHIP_ID[15:8]
R-0x00h
7
6
5
4
CHIP_ID[7:0]
R-0x20h
Table 50. CHIP_ID Field Descriptions
Bit
15-0
86
Field
Type
Reset
Description
CHIP_ID
R
0x0020h
Always returns 0x0020, indicating that this device is part of the
ADC12DJxx00 family.
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7.6.1.1.5 Chip Version Register (address = 0x006) [reset = 0x01]
Figure 92. Chip Version Register (CHIP_VERSION)
7
6
5
4
3
CHIP_VERSION
R-0000 1010
2
1
0
Table 51. CHIP_VERSION Field Descriptions
Bit
Field
Type
Reset
7-0
CHIP_VERSION
R
0000 1010 Chip version, returns 0x0A.
Description
7.6.1.1.6 Vendor Identification Register (address = 0x00C to 0x00D) [reset = 0x0451]
Figure 93. Vendor Identification Register (VENDOR_ID)
15
14
13
12
11
VENDOR_ID[15:8]
R-0x04h
10
9
8
7
6
5
4
3
VENDOR_ID[7:0]
R-0x51h
2
1
0
Table 52. VENDOR_ID Field Descriptions
Bit
15-0
Field
Type
Reset
Description
VENDOR_ID
R
0x0451h
Always returns 0x0451 (TI vendor ID).
7.6.1.2 User SPI Configuration (0x010 to 0x01F)
Table 53. User SPI Configuration Registers
ADDRESS
RESET
ACRONYM
0x010
0x00
USR0
0x011-0x01F
Undefined
RESERVED
REGISTER NAME
User SPI Configuration Register
SECTION
User SPI Configuration Register (address = 0x010) [reset
= 0x00]
RESERVED
—
7.6.1.2.1 User SPI Configuration Register (address = 0x010) [reset = 0x00]
Figure 94. User SPI Configuration Register (USR0)
7
6
5
4
RESERVED
R-0000 000
3
2
1
0
ADDR_HOLD
R/W-0
Table 54. USR0 Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
ADDR_HOLD
R/W
0
0: Use the ADDR_ASC bit to define what happens to the
address during streaming (default)
1: Address remains static throughout streaming operation; this
setting is useful for reading/writing calibration vector information
at the CAL_DATA register
0
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7.6.1.3 Miscellaneous Analog Registers (0x020 to 0x047)
Table 55. Miscellaneous Analog Registers
ADDRESS
RESET
ACRONYM
0x020-0x028
Undefined
RESERVED
RESERVED
REGISTER NAME
SECTION
—
0x029
0x00
CLK_CTRL0
Clock Control Register 0
Clock Control Register 0 (address = 0x029) [reset = 0x00]
0x02A
0x20
CLK_CTRL1
Clock Control Register 1
Clock Control Register 1 (address = 0x02A) [reset = 0x00]
RESERVED
0x02B
Undefined
RESERVED
0x02C-0x02E
Undefined
SYSREF_POS
—
SYSREF Capture Position Register
SYSREF Capture Position Register (address = 0x02C0x02E) [reset = Undefined]
0x02F
Undefined
RESERVED
0x030-0x031
0xA000
FS_RANGE_A
RESERVED
INA Full-Scale Range Adjust Register
INA Full-Scale Range Adjust Register (address = 0x0300x031) [reset = 0xA000]
—
0x032-0x033
0xA000
FS_RANGE_B
INB Full-Scale Range Adjust Register
INB Full-Scale Range Adjust Register (address = 0x0320x033) [reset = 0xA000]
0x034-0x037
Undefined
RESERVED
RESERVED
0x038
0x00
BG_BYPASS
Internal Reference Bypass Register
0x039-0x03A
Undefined
RESERVED
RESERVED
0x03B
0x00
SYNC_CTRL
TMSTP± Control Register
0x03C-0x047
Undefined
RESERVED
RESERVED
—
Internal Reference Bypass Register (address = 0x038)
[reset = 0x00]
—
TMSTP± Control Register (address = 0x03B) [reset =
0x00]
—
7.6.1.3.1 Clock Control Register 0 (address = 0x029) [reset = 0x00]
Figure 95. Clock Control Register 0 (CLK_CTRL0)
7
RESERVED
R/W-0
6
SYSREF_PROC_EN
R/W-0
5
SYSREF_RECV_EN
R/W-0
4
SYSREF_ZOOM
R/W-0
3
2
1
SYSREF_SEL
R/W-0000
0
Table 56. CLK_CTRL0 Field Descriptions
Bit
Field
Type
Reset
Description
7
RESERVED
R/W
0
RESERVED
6
SYSREF_PROC_EN
R/W
0
This bit enables the SYSREF processor. This bit must be set to
allow the device to process SYSREF events.
SYSREF_RECV_EN must be set before setting
SYSREF_PROC_EN.
5
SYSREF_RECV_EN
R/W
0
Set this bit to enable the SYSREF receiver circuit.
4
SYSREF_ZOOM
R/W
0
Set this bit to zoom in the SYSREF strobe status (affects
SYSREF_POS).
SYSREF_SEL
R/W
0000
Set this field to select which SYSREF delay to use. Set this field
based on the results returned by SYSREF_POS. Set this field to
0 to use SYSREF calibration.
3-0
88
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7.6.1.3.2 Clock Control Register 1 (address = 0x02A) [reset = 0x00]
Figure 96. Clock Control Register 1 (CLK_CTRL1)
7
6
5
RESERVED
R/W-0010 0
4
3
2
DEVCLK_LVPECL_EN
R/W-0
1
SYSREF_LVPECL_EN
R/W-0
0
SYSREF_INVERTED
R/W-0
Table 57. CLK_CTRL1 Field Descriptions
Bit
Field
Type
Reset
Description
7-3
RESERVED
R/W
0010 0
RESERVED
2
DEVCLK_LVPECL_EN
R/W
0
Activate low-voltage PECL mode for DEVCLK.
1
SYSREF_LVPECL_EN
R/W
0
Activate low-voltage PECL mode for SYSREF.
0
SYSREF_INVERTED
R/W
0
Inverts the SYSREF signal used for alignment.
7.6.1.3.3 SYSREF Capture Position Register (address = 0x02C-0x02E) [reset = Undefined]
Figure 97. SYSREF Capture Position Register (SYSREF_POS)
23
22
21
15
14
13
7
6
5
20
19
SYSREF_POS[23:16]
R-Undefined
12
11
SYSREF_POS[15:8]
R-Undefined
4
3
SYSREF_POS[7:0]
R-Undefined
18
17
16
10
9
8
2
1
0
Table 58. SYSREF_POS Field Descriptions
Bit
23-0
Field
Type
Reset
Description
SYSREF_POS
R
Undefined
This field returns a 24-bit status value that indicates the position
of the SYSREF edge with respect to DEVCLK. Use this field to
program SYSREF_SEL.
7.6.1.3.4 INA Full-Scale Range Adjust Register (address = 0x030-0x031) [reset = 0xA000]
Figure 98. INA Full-Scale Range Adjust Register (FS_RANGE_A)
15
14
13
7
6
5
12
11
FS_RANGE_A[15:8]
R/W-0xA0h
4
3
FS_RANGE_A[7:0]
R/W-0x00h
10
9
8
2
1
0
Table 59. FS_RANGE_A Field Descriptions
Bit
15-0
Field
Type
Reset
Description
FS_RANGE_A
R/W
0xA000h
This field enables adjustment of the analog full-scale range for
INA.
0x0000: Settings below 0x2000 may result in degraded device
performance
0x2000: 500 mVPP - Recommended minimum setting
0xA000: 800 mVPP (default)
0xFFFF: 1000 mVPP
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7.6.1.3.5 INB Full-Scale Range Adjust Register (address = 0x032-0x033) [reset = 0xA000]
Figure 99. INB Full Scale Range Adjust Register (FS_RANGE_B)
15
14
13
7
6
5
12
11
FS_RANGE_B[15:8]
R/W-0xA0
4
3
FS_RANGE_B[7:0]
R/W-0x00
10
9
8
2
1
0
Table 60. FS_RANGE_B Field Descriptions
Bit
15-0
Field
Type
Reset
Description
FS_RANGE_B
R/W
0xA000h
This field enables adjustment of the analog full-scale range for
INB.
0x0000: Settings below 0x2000 may result in degraded device
performance
0x2000: 500 mVPP - Recommended minimum setting
0xA000: 800 mVPP (default)
0xFFFF: 1000 mVPP
7.6.1.3.6 Internal Reference Bypass Register (address = 0x038) [reset = 0x00]
Figure 100. Internal Reference Bypass Register (BG_BYPASS)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
BG_BYPASS
R/W-0
Table 61. BG_BYPASS Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
0
BG_BYPASS
R/W
0
When set, VA11 is used as the voltage reference instead of the
internal reference.
7.6.1.3.7 TMSTP± Control Register (address = 0x03B) [reset = 0x00]
Figure 101. TMSTP± Control Register (TMSTP_CTRL)
7
6
5
4
RESERVED
R/W-0000 00
3
2
1
TMSTP_LVPECL_EN
R/W-0
0
TMSTP_RECV_EN
R/W-0
Table 62. TMSTP_CTRL Field Descriptions
90
Bit
Field
Type
Reset
Description
7-2
RESERVED
R/W
0000 00
RESERVED
1
TMSTP_LVPECL_EN
R/W
0
When set, this bit activates the low-voltage PECL mode for the
differential TMSTP± input.
0
TMSTP_RECV_EN
R/W
0
This bit enables the differential TMSTP± input.
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7.6.1.4 Serializer Registers (0x048 to 0x05F)
Table 63. Serializer Registers
ADDRESS
RESET
ACRONYM
0x048
0x00
SER_PE
0x049-0x05F
Undefined
RESERVED
REGISTER NAME
Serializer Pre-Emphasis Control
Register
SECTION
Serializer Pre-Emphasis Control Register (address =
0x048) [reset = 0x00]
RESERVED
—
7.6.1.4.1 Serializer Pre-Emphasis Control Register (address = 0x048) [reset = 0x00]
Figure 102. Serializer Pre-Emphasis Control Register (SER_PE)
7
6
5
4
3
RESERVED
R/W-0000
2
1
0
SER_PE
R/W-0000
Table 64. SER_PE Field Descriptions
Bit
Field
Type
Reset
Description
7-4
RESERVED
R/W
0000
RESERVED
3-0
SER_PE
R/W
0000
This field sets the pre-emphasis for the serial lanes to
compensate for the low-pass response of the PCB trace. This
setting is a global setting that affects all 16 lanes.
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7.6.1.5 Calibration Registers (0x060 to 0x0FF)
Table 65. Calibration Registers
92
ADDRESS
RESET
ACRONYM
0x060
0x01
INPUT_MUX
Input Mux Control Register
REGISTER NAME
Input Mux Control Register (address = 0x060) [reset =
0x01]
0x061
0x01
CAL_EN
Calibration Enable Register
Calibration Enable Register (address = 0x061) [reset =
0x01]
0x062
0x01
CAL_CFG0
Calibration Configuration 0 Register
Calibration Configuration 0 Register (address = 0x062)
[reset = 0x01]
0x063-0x069
Undefined
RESERVED
RESERVED
0x06A
Undefined
CAL_STATUS
Calibration Status Register
0x06B
0x00
CAL_PIN_CFG
Calibration Pin Configuration
Register
0x06C
0x01
0x06D
Undefined
RESERVED
0x06E
0x88
CAL_LP
0x06F
Undefined
RESERVED
0x070
0x00
CAL_DATA_EN
0x071
Undefined
CAL_DATA
Calibration Data Register
0x072-0x079
Undefined
RESERVED
RESERVED
0x07A
Undefined
GAIN_TRIM_A
Channel A Gain Trim Register
Channel A Gain Trim Register (address = 0x07A) [reset =
Undefined]
0x07B
Undefined
GAIN_TRIM_B
Channel B Gain Trim Register
Channel B Gain Trim Register (address = 0x07B) [reset =
Undefined]
0x07C
Undefined
BG_TRIM
0x07D
Undefined
RESERVED
0x07E
Undefined
RTRIM_A
VINA Input Resistor Trim Register
VINA Input Resistor Trim Register (address = 0x07E)
[reset = Undefined]
0x07F
Undefined
RTRIM_B
VINB Input Resistor Trim Register
VINB Input Resistor Trim Register (address = 0x07F)
[reset = Undefined]
0x080
Undefined
TADJ_A_FG90
Timing Adjustment for A-ADC,
Single-Channel Mode, Foreground
Calibration Register
Timing Adjust for A-ADC, Single-Channel Mode,
Foreground Calibration Register (address = 0x080) [reset
= Undefined]
0x081
Undefined
TADJ_B_FG0
Timing Adjustment for B-ADC,
Single-Channel Mode, Foreground
Calibration Register
Timing Adjust for B-ADC, Single-Channel Mode,
Foreground Calibration Register (address = 0x081) [reset
= Undefined]
0x082
Undefined
TADJ_A_BG90
Timing Adjustment for A-ADC,
Single-Channel Mode, Background
Calibration Register
Timing Adjust for A-ADC, Single-Channel Mode,
Background Calibration Register (address = 0x082) [reset
= Undefined]
0x083
Undefined
TADJ_C_BG0
Timing Adjustment for C-ADC,
Single-Channel Mode, Background
Calibration Register
Timing Adjust for C-ADC, Single-Channel Mode,
Background Calibration Register (address = 0x084) [reset
= Undefined]
0x084
Undefined
TADJ_C_BG90
Timing Adjustment for C-ADC,
Single-Channel Mode, Background
Calibration Register
Timing Adjust for C-ADC, Single-Channel Mode,
Background Calibration Register (address = 0x084) [reset
= Undefined]
0x085
Undefined
TADJ_B_BG0
Timing Adjustment for B-ADC,
Single-Channel Mode, Background
Calibration Register
Timing Adjust for B-ADC, Single-Channel Mode,
Background Calibration Register (address = 0x085) [reset
= Undefined]
0x086
Undefined
TADJ_A
Timing Adjustment for A-ADC, DualChannel Mode Register
Timing Adjust for A-ADC, Dual-Channel Mode Register
(address = 0x086) [reset = Undefined]
0x087
Undefined
TADJ_CA
Timing Adjustment for C-ADC Acting
for A-ADC, Dual-Channel Mode
Register
Timing Adjust for C-ADC Acting for A-ADC, Dual-Channel
Mode Register (address = 0x087) [reset = Undefined]
0x088
Undefined
TADJ_CB
Timing Adjustment for C-ADC Acting
for B-ADC, Dual-Channel Mode
Register
Timing Adjust for C-ADC Acting for B-ADC, Dual-Channel
Mode Register (address = 0x088) [reset = Undefined]
CAL_SOFT_TRIG Calibration Software Trigger Register
RESERVED
Low-Power Background Calibration
Register
RESERVED
Calibration Data Enable Register
Band-Gap Reference Trim Register
RESERVED
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SECTION
—
Calibration Status Register (address = 0x06A) [reset =
Undefined]
Calibration Pin Configuration Register (address = 0x06B)
[reset = 0x00]
Calibration Software Trigger Register (address = 0x06C)
[reset = 0x01]
—
Low-Power Background Calibration Register (address =
0x06E) [reset = 0x88]
—
Calibration Data Enable Register (address = 0x070) [reset
= 0x00]
Calibration Data Register (address = 0x071) [reset =
Undefined]
—
Band-Gap Reference Trim Register (address = 0x07C)
[reset = Undefined]
—
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Table 65. Calibration Registers (continued)
ADDRESS
RESET
ACRONYM
0x089
Undefined
TADJ_B
REGISTER NAME
SECTION
0x08A-0x08B
Undefined
OADJ_A_INA
Offset Adjustment for A-ADC and INA Offset Adjustment for A-ADC and INA Register (address =
Register
0x08A-0x08B) [reset = Undefined]
0x08C-0x08D
Undefined
OADJ_A_INB
Offset Adjustment for A-ADC and INB Offset Adjustment for A-ADC and INB Register (address =
Register
0x08C-0x08D) [reset = Undefined]
0x08E-0x08F
Undefined
OADJ_C_INA
Offset Adjustment for C-ADC and
INA Register
Offset Adjustment for C-ADC and INA Register (address =
0x08E-0x08F) [reset = Undefined]
0x090-0x091
Undefined
OADJ_C_INB
Offset Adjustment for C-ADC and
INB Register
Offset Adjustment for C-ADC and INB Register (address =
0x090-0x091) [reset = Undefined]
0x092-0x093
Undefined
OADJ_B_INA
Offset Adjustment for B-ADC and INA Offset Adjustment for B-ADC and INA Register (address =
Register
0x092-0x093) [reset = Undefined]
0x094-0x095
Undefined
OADJ_B_INB
Offset Adjustment for B-ADC and INB Offset Adjustment for B-ADC and INB Register (address =
Register
0x094-0x095) [reset = Undefined]
0x096
Undefined
RESERVED
RESERVED
0x097
0x00
0SFILT0
Offset Filtering Control 0
Offset Filtering Control 0 Register (address = 0x097)
[reset = 0x00]
0x098
0x33
OSFILT1
Offset Filtering Control 1
Offset Filtering Control 1 Register (address = 0x098)
[reset = 0x33]
0x099-0x0FF
Undefined
RESERVED
Timing Adjustment for B-ADC, DualChannel Mode Register
Timing Adjust for B-ADC, Dual-Channel Mode Register
(address = 0x089) [reset = Undefined]
—
RESERVED
—
7.6.1.5.1 Input Mux Control Register (address = 0x060) [reset = 0x01]
Figure 103. Input Mux Control Register (INPUT_MUX)
7
6
RESERVED
R/W-000
5
4
DUAL_INPUT
R/W-0
3
2
RESERVED
R/W-00
1
0
SINGLE_INPUT
R/W-01
Table 66. INPUT_MUX Field Descriptions
Bit
Field
Type
Reset
Description
7-5
RESERVED
R/W
000
RESERVED
DUAL_INPUT
R/W
0
This bit selects inputs for dual-channel modes. If JMODE is
selecting a single-channel mode, this register has no effect.
0: A channel samples INA, B channel samples INB (no swap,
default)
1: A channel samples INB, B channel samples INA (swap)
3-2
RESERVED
R/W
00
RESERVED
1-0
SINGLE_INPUT
R/W
01
Thid field defines which input is sampled in single-channel
mode. If JMODE is not selecting a single-channel mode, this
register has no effect.
0: Reserved
1: INA is used (default)
2: INB is used
3: Reserved
4
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7.6.1.5.2 Calibration Enable Register (address = 0x061) [reset = 0x01]
Figure 104. Calibration Enable Register (CAL_EN)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
CAL_EN
R/W-1
Table 67. CAL_EN Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
CAL_EN
R/W
1
Calibration enable. Set this bit high to run calibration. Set this bit
low to hold the calibration in reset to program new calibration
settings. Clearing CAL_EN also resets the clock dividers that
clock the digital block and JESD204B interface.
Some calibration registers require clearing CAL_EN before
making any changes. All registers with this requirement contain
a note in their descriptions. After changing the registers, set
CAL_EN to re-run calibration with the new settings.
Always set CAL_EN before setting JESD_EN. Always clear
JESD_EN before clearing CAL_EN.
0
7.6.1.5.3 Calibration Configuration 0 Register (address = 0x062) [reset = 0x01]
Only change this register when CAL_EN is 0.
Figure 105. Calibration Configuration 0 Register (CAL_CFG0)
7
6
RESERVED
R/W-000
5
4
CAL_OSFILT
R/W-0
3
CAL_BGOS
R/W-0
2
CAL_OS
R/W-0
1
CAL_BG
R/W-0
0
CAL_FG
R/W-1
Table 68. CAL_CFG0 Field Descriptions
94
Bit
Field
Type
Reset
Description
7-5
RESERVED
R/W
0000
RESERVED
4
CAL_OSFILT
R/W
0
Enable offset filtering by setting this bit high.
3
CAL_BGOS
R/W
0
0 : Disables background offset calibration (default)
1: Enables background offset calibration (requires CAL_BG to
be set).
2
CAL_OS
R/W
0
0 : Disables foreground offset calibration (default)
1: Enables foreground offset calibration (requires CAL_FG to be
set)
1
CAL_BG
R/W
0
0 : Disables background calibration (default)
1: Enables background calibration
0
CAL_FG
R/W
1
0 : Resets calibration values, skips foreground calibration
1: Resets calibration values, then runs foreground calibration
(default)
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7.6.1.5.4 Calibration Status Register (address = 0x06A) [reset = Undefined]
Figure 106. Calibration Status Register (CAL_STATUS)
7
6
5
4
3
2
1
CAL_STOPPED
R
RESERVED
R
0
FG_DONE
R
Table 69. CAL_STATUS Field Descriptions
Bit
Field
Type
7-2
RESERVED
R
Reset
Description
RESERVED
1
CAL_STOPPED
R
This bit returns a 1 when the background calibration has
successfully stopped at the requested phase. This bit returns a 0
when calibration starts operating again. If background calibration
is disabled, this bit is set when foreground calibration is
completed or skipped.
0
FG_DONE
R
This bit is set high when the foreground calibration completes.
7.6.1.5.5 Calibration Pin Configuration Register (address = 0x06B) [reset = 0x00]
Figure 107. Calibration Pin Configuration Register (CAL_PIN_CFG)
7
6
5
RESERVED
R/W-0000 0
4
3
2
1
CAL_STATUS_SEL
R/W-00
0
CAL_TRIG_EN
R/W-0
Table 70. CAL_PIN_CFG Field Descriptions
Bit
Field
Type
Reset
Description
7-3
RESERVED
R/W
0000 0
RESERVED
2-1
CAL_STATUS_SEL
R/W
00
0: CALSTAT output pin matches FG_DONE
1: RESERVED
2: CALSTAT output pin matches ALARM
3: CALSTAT output pin is always low
CAL_TRIG_EN
R/W
0
Choose the hardware or software trigger source with this bit.
0: Use the CAL_SOFT_TRIG register for the calibration trigger;
the CAL_TRIG input is disabled (ignored)
1: Use the CAL_TRIG input for the calibration trigger; the
CAL_SOFT_TRIG register is ignored
0
7.6.1.5.6 Calibration Software Trigger Register (address = 0x06C) [reset = 0x01]
Figure 108. Calibration Software Trigger Register (CAL_SOFT_TRIG)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
CAL_SOFT_TRIG
R/W-1
Table 71. CAL_SOFT_TRIG Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
CAL_SOFT_TRIG
R/W
1
CAL_SOFT_TRIG is a software bit to provide functionality of the
CAL_TRIG input. Program CAL_TRIG_EN = 0 to use
CAL_SOFT_TRIG for the calibration trigger. If no calibration
trigger is needed, leave CAL_TRIG_EN = 0 and
CAL_SOFT_TRIG = 1 (trigger is set high).
0
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7.6.1.5.7 Low-Power Background Calibration Register (address = 0x06E) [reset = 0x88]
Figure 109. Low-Power Background Calibration Register (CAL_LP)
7
6
LP_SLEEP_DLY
R/W-010
5
4
3
2
RESERVED
R/W-0
LP_WAKE_DLY
R/W-01
1
LP_TRIG
R/W-0
0
LP_EN
R/W-0
Table 72. CAL_LP Field Descriptions
Bit
Field
Type
Reset
Description
7-5
LP_SLEEP_DLY
R/W
010
Adjust how long an ADC sleeps before waking up for calibration
(only applies when LP_EN = 1 and LP_TRIG = 0). Values below
4 are not recommended because of limited overall power
reduction benefits.
0: Sleep delay = (23 + 1) × 256 × tDEVCLK
1: Sleep delay = (215 + 1) × 256 × tDEVCLK
2: Sleep delay = (218 + 1) × 256 × tDEVCLK
3: Sleep delay = (221 + 1) × 256 × tDEVCLK
4: Sleep delay = (224 + 1) × 256 × tDEVCLK : default is
approximately 1338 ms with a 3.2-GHz clock
5: Sleep delay = (227 + 1) × 256 × tDEVCLK
6: Sleep delay = (230 + 1) × 256 × tDEVCLK
7: Sleep delay = (233 + 1) × 256 × tDEVCLK
4-3
LP_WAKE_DLY
R/W
01
Adjust how much time is given up for settling before calibrating
an ADC after wake-up (only applies when LP_EN = 1). Values
lower than 1 are not recommended because there is insufficient
time for the core to stabilize before calibration begins.
0:Wake Delay = (23 + 1) × 256 × tDEVCLK
1: Wake Delay = (218 + 1) × 256 × tDEVCLK : default is
approximately 21 ms with a 3.2-GHz clock
2: Wake Delay = (221 + 1) × 256 × tDEVCLK
3: Wake Delay = (224 + 1) × 256 × tDEVCLK
2
RESERVED
R/W
0
RESERVED
1
LP_TRIG
R/W
0
0: ADC sleep duration is set by LP_SLEEP_DLY (autonomous
mode)
1: ADCs sleep until woken by a trigger; an ADC is awoken when
the calibration trigger (CAL_SOFT_TRIG bit or CAL_TRIG input)
is low
0
LP_EN
R/W
0
0: Disables low-power background calibration (default)
1: Enables low-power background calibration (only applies when
CAL_BG = 1)
7.6.1.5.8 Calibration Data Enable Register (address = 0x070) [reset = 0x00]
Figure 110. Calibration Data Enable Register (CAL_DATA_EN)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
CAL_DATA_EN
R/W-0
Table 73. CAL_DATA_EN Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
CAL_DATA_EN
R/W
0
Set this bit to enable the CAL_DATA register to enable reading
and writing of calibration data; see the calibration data register
for more information.
0
96
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7.6.1.5.9 Calibration Data Register (address = 0x071) [reset = Undefined]
Figure 111. Calibration Data Register (CAL_DATA)
7
6
5
4
3
2
1
0
CAL_DATA
R/W
Table 74. CAL_DATA Field Descriptions
Bit
Field
Type
Reset
Description
7-0
CAL_DATA
R/W
Undefined
After setting CAL_DATA_EN, repeated reads of this register
return all calibration values for the ADCs. Repeated writes of this
register input all calibration values for the ADCs. To read the
calibration data, read the register 673 times. To write the vector,
write the register 673 times with previously stored calibration
data.
To speed up the read/write operation, set ADDR_HOLD = 1 and
use the streaming read or write process.
Accessing the CAL_DATA register when CAL_STOPPED = 0
corrupts the calibration. Also, stopping the process before
reading or writing 673 times leaved the calibration data in an
invalid state.
7.6.1.5.10 Channel A Gain Trim Register (address = 0x07A) [reset = Undefined]
Figure 112. Channel A Gain Trim Register (GAIN_TRIM_A)
7
6
5
4
3
2
1
0
GAIN_TRIM_A
R/W
Table 75. GAIN_TRIM_A Field Descriptions
Bit
Field
Type
Reset
Description
7-0
GAIN_TRIM_A
R/W
Undefined
This register enables gain trim of channel A. After reset, the
factory-trimmed value can be read and adjusted as required.
7.6.1.5.11 Channel B Gain Trim Register (address = 0x07B) [reset = Undefined]
Figure 113. Channel B Gain Trim Register (GAIN_TRIM_B)
7
6
5
4
3
2
1
0
GAIN_TRIM_B
R/W
Table 76. GAIN_TRIM_B Field Descriptions
Bit
Field
Type
Reset
Description
7-0
GAIN_TRIM_B
R/W
Undefined
This register enables gain trim of channel B. After reset, the
factory-trimmed value can be read and adjusted as required.
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7.6.1.5.12 Band-Gap Reference Trim Register (address = 0x07C) [reset = Undefined]
Figure 114. Band-Gap Reference Trim Register (BG_TRIM)
7
6
5
4
3
2
RESERVED
R/W-0000
1
0
BG_TRIM
R/W
Table 77. BG_TRIM Field Descriptions
Bit
Field
Type
Reset
Description
7-4
RESERVED
R/W
0000
RESERVED
3-0
BG_TRIM
R/W
Undefined
This register enables the internal band-gap reference to be
trimmed. After reset, the factory-trimmed value can be read and
adjusted as required.
7.6.1.5.13 VINA Input Resistor Trim Register (address = 0x07E) [reset = Undefined]
Figure 115. VINA Input Resistor Trim Register (RTRIM_A)
7
6
5
4
3
2
1
0
RTRIM
R/W
Table 78. RTRIM_A Field Descriptions
Bit
Field
Type
Reset
Description
7-0
RTRIM_A
R/W
Undefined
This register controls the VINA ADC input termination trim. After
reset, the factory-trimmed value can be read and adjusted as
required.
7.6.1.5.14 VINB Input Resistor Trim Register (address = 0x07F) [reset = Undefined]
Figure 116. VINB Input Resistor Trim Register (RTRIM_B)
7
6
5
4
3
2
1
0
RTRIM
R/W
Table 79. RTRIM_B Field Descriptions
98
Bit
Field
Type
Reset
Description
7-0
RTRIM_B
R/W
Undefined
This register controls the VINB ADC input termination trim. After
reset, the factory-trimmed value can be read and adjusted as
required.
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7.6.1.5.15 Timing Adjust for A-ADC, Single-Channel Mode, Foreground Calibration Register (address = 0x080) [reset
= Undefined]
Figure 117. Register (TADJ_A_FG90)
7
6
5
4
3
2
1
0
TADJ_A_FG90
R/W
Table 80. TADJ_A_FG90 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_A_FG90
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
7.6.1.5.16 Timing Adjust for B-ADC, Single-Channel Mode, Foreground Calibration Register (address = 0x081) [reset
= Undefined]
Figure 118. Register (TADJ_B_FG0)
7
6
5
4
3
2
1
0
TADJ_B_FG0
R/W
Table 81. TADJ_B_FG0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_B_FG0
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
7.6.1.5.17 Timing Adjust for A-ADC, Single-Channel Mode, Background Calibration Register (address = 0x082)
[reset = Undefined]
Figure 119. Register (TADJ_A_BG90)
7
6
5
4
3
2
1
0
TADJ_A_BG90
R/W
Table 82. TADJ_B_FG0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_A_BG90
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
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7.6.1.5.18 Timing Adjust for C-ADC, Single-Channel Mode, Background Calibration Register (address = 0x083)
[reset = Undefined]
Figure 120. Timing Adjust for C-ADC, Single-Channel Mode, Background Calibration Register
(TADJ_C_BG0)
7
6
5
4
3
2
1
0
TADJ_C_BG0
R/W
Table 83. TADJ_B_FG0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_C_BG0
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
7.6.1.5.19 Timing Adjust for C-ADC, Single-Channel Mode, Background Calibration Register (address = 0x084)
[reset = Undefined]
Figure 121. Timing Adjust for C-ADC, Single-Channel Mode, Background Calibration Register
(TADJ_C_BG90)
7
6
5
4
3
2
1
0
TADJ_C_BG90
R/W
Table 84. TADJ_B_FG0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_C_BG90
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
7.6.1.5.20 Timing Adjust for B-ADC, Single-Channel Mode, Background Calibration Register (address = 0x085)
[reset = Undefined]
Figure 122. Timing Adjust for B-ADC, Single-Channel Mode, Background Calibration Register
(TADJ_B_BG0)
7
6
5
4
3
2
1
0
TADJ_B_BG0
R/W
Table 85. TADJ_B_FG0 Field Descriptions
100
Bit
Field
Type
Reset
Description
7-0
TADJ_B_BG0
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
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7.6.1.5.21 Timing Adjust for A-ADC, Dual-Channel Mode Register (address = 0x086) [reset = Undefined]
Figure 123. Timing Adjust for A-ADC, Dual-Channel Mode Register (TADJ_A)
7
6
5
4
3
2
1
0
TADJ_A
R/W
Table 86. TADJ_A Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_A
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
7.6.1.5.22 Timing Adjust for C-ADC Acting for A-ADC, Dual-Channel Mode Register (address = 0x087) [reset =
Undefined]
Figure 124. Timing Adjust for C-ADC Acting for A-ADC, Dual-Channel Mode Register (TADJ_CA)
7
6
5
4
3
2
1
0
TADJ_CA
R/W
Table 87. TADJ_CA Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_CA
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
7.6.1.5.23 Timing Adjust for C-ADC Acting for B-ADC, Dual-Channel Mode Register (address = 0x088) [reset =
Undefined]
Figure 125. Timing Adjust for C-ADC Acting for B-ADC, Dual-Channel Mode Register (TADJ_CB)
7
6
5
4
3
2
1
0
TADJ_CB
R/W
Table 88. TADJ_CB Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_CB
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
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7.6.1.5.24 Timing Adjust for B-ADC, Dual-Channel Mode Register (address = 0x089) [reset = Undefined]
Figure 126. Timing Adjust for B-ADC, Dual-Channel Mode Register (TADJ_B)
7
6
5
4
3
2
1
0
TADJ_B
R/W
Table 89. TADJ_B Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TADJ_B
R/W
Undefined
This register (and other subsequent TADJ* registers) are used
to adjust the sampling instant of each ADC core. Different TADJ
registers apply to different ADCs under different modes or
phases of background calibration. After reset, the factorytrimmed value can be read and adjusted as required.
7.6.1.5.25 Offset Adjustment for A-ADC and INA Register (address = 0x08A-0x08B) [reset = Undefined]
Figure 127. Offset Adjustment for A-ADC and INA Register (OADJ_A_INA)
15
14
13
12
11
5
4
3
OADJ_A_INA[7:0]
R/W
RESERVED
R/W-0000
7
6
10
9
OADJ_A_INA[11:8]
R/W
2
1
8
0
Table 90. OADJ_A_INA Field Descriptions
Field
Type
Reset
Description
15-12
Bit
RESERVED
R/W
0000
RESERVED
11-0
OADJ_A_INA
R/W
Undefined
Offset adjustment value for ADC0 (A-ADC) applied when ADC0
samples INA. The format is unsigned. After reset, the factorytrimmed value can be read and adjusted as required.
Important notes:
•
Never write OADJ* registers while foreground calibration is
underway
•
Never write OADJ* registers if CAL_BG and CAL_BGOS
are set
•
If CAL_OS = 1 and CAL_BGOS = 0, only read OADJ*
registers if FG_DONE = 1
•
If CAL_BG = 1 and CAL_BGOS = 1, only read OADJ*
register if CAL_STOPPED = 1
102
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7.6.1.5.26 Offset Adjustment for A-ADC and INB Register (address = 0x08C-0x08D) [reset = Undefined]
Figure 128. Offset Adjustment for A-ADC and INB Register (OADJ_A_INB)
15
14
13
12
11
5
4
3
OADJ_A_INB[7:0]
R/W
RESERVED
R/W-0000
7
6
10
9
OADJ_A_INB[11:8]
R/W
2
1
8
0
Table 91. OADJ_A_INB Field Descriptions
Field
Type
Reset
Description
15-12
Bit
RESERVED
R/W
0000
RESERVED
11-0
OADJ_A_INB
R/W
Undefined
Offset adjustment value for ADC0 (A-ADC) applied when ADC0
samples INB. The format is unsigned. After reset, the factorytrimmed value can be read and adjusted as required.
Important notes:
•
Never write OADJ* registers while foreground calibration is
underway
•
Never write OADJ* registers if CAL_BG and CAL_BGOS
are set
•
If CAL_OS = 1 and CAL_BGOS = 0, only read OADJ*
registers if FG_DONE = 1
•
If CAL_BG = 1 and CAL_BGOS = 1, only read OADJ*
register if CAL_STOPPED = 1
7.6.1.5.27 Offset Adjustment for C-ADC and INA Register (address = 0x08E-0x08F) [reset = Undefined]
Figure 129. Offset Adjustment for C-ADC and INA Register (OADJ_C_INA)
15
14
13
12
11
5
4
3
OADJ_C_INA[7:0]
R/W
RESERVED
R/W-0000
7
6
10
9
OADJ_C_INA[11:8]
R/W
2
1
8
0
Table 92. OADJ_C_INA Field Descriptions
Bit
Field
Type
Reset
Description
15-12
RESERVED
R/W
0000
RESERVED
11-0
OADJ_C_INA
R/W
Undefined
Offset adjustment value for ADC1 (A-ADC) applied when ADC1
samples INA. The format is unsigned. After reset, the factorytrimmed value can be read and adjusted as required.
Important notes:
•
Never write OADJ* registers while foreground calibration is
underway
•
Never write OADJ* registers if CAL_BG and CAL_BGOS
are set
•
If CAL_OS = 1 and CAL_BGOS = 0, only read OADJ*
registers if FG_DONE = 1
•
If CAL_BG = 1 and CAL_BGOS = 1, only read OADJ*
register if CAL_STOPPED = 1
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7.6.1.5.28 Offset Adjustment for C-ADC and INB Register (address = 0x090-0x091) [reset = Undefined]
Figure 130. Offset Adjustment for C-ADC and INB Register (OADJ_C_INB)
15
14
13
12
11
5
4
3
OADJ_C_INB[7:0]
R/W
RESERVED
R/W-0000
7
6
10
9
OADJ_C_INB[11:8]
R/W
2
1
8
0
Table 93. OADJ_C_INB Field Descriptions
Field
Type
Reset
Description
15-12
Bit
RESERVED
R/W
0000
RESERVED
11-0
OADJ_C_INB
R/W
Undefined
Offset adjustment value for ADC1 (A-ADC) applied when ADC1
samples INB. The format is unsigned. After reset, the factorytrimmed value can be read and adjusted as required.
Important notes:
•
Never write OADJ* registers while foreground calibration is
underway
•
Never write OADJ* registers if CAL_BG and CAL_BGOS
are set
•
If CAL_OS = 1 and CAL_BGOS = 0, only read OADJ*
registers if FG_DONE = 1
•
If CAL_BG = 1 and CAL_BGOS = 1, only read OADJ*
register if CAL_STOPPED = 1
7.6.1.5.29 Offset Adjustment for B-ADC and INA Register (address = 0x092-0x093) [reset = Undefined]
Figure 131. Offset Adjustment for B-ADC and INA Register (OADJ_B_INA)
15
14
13
12
11
5
4
3
OADJ_B_INA[7:0]
R/W
RESERVED
R/W-0000
7
6
10
9
OADJ_B_INA[11:8]
R/W
2
1
8
0
Table 94. OADJ_B_INA Field Descriptions
Bit
Field
Type
Reset
Description
15-12
RESERVED
R/W
0000
RESERVED
11-0
OADJ_B_INA
R/W
Undefined
Offset adjustment value for ADC2 (B-ADC) applied when ADC2
samples INA. The format is unsigned. After reset, the factorytrimmed value can be read and adjusted as required.
Important notes:
•
Never write OADJ* registers while foreground calibration is
underway
•
Never write OADJ* registers if CAL_BG and CAL_BGOS
are set
•
If CAL_OS = 1 and CAL_BGOS = 0, only read OADJ*
registers if FG_DONE = 1
•
If CAL_BG = 1 and CAL_BGOS = 1, only read OADJ*
register if CAL_STOPPED = 1
104
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7.6.1.5.30 Offset Adjustment for B-ADC and INB Register (address = 0x094-0x095) [reset = Undefined]
Figure 132. Offset Adjustment for B-ADC and INB Register (OADJ_B_INB)
15
14
13
12
11
5
4
3
OADJ_B_INB[7:0]
R/W
10
9
OADJ_B_INB[11:8]
R/W
2
1
RESERVED
R/W-0000
7
6
8
0
Table 95. OADJ_B_INB Field Descriptions
Field
Type
Reset
Description
15-12
Bit
RESERVED
R/W
0000
RESERVED
11-0
OADJ_B_INB
R/W
Undefined
Offset adjustment value for ADC2 (B-ADC) applied when ADC2
samples INB. The format is unsigned. After reset, the factorytrimmed value can be read and adjusted as required.
Important notes:
•
Never write OADJ* registers while foreground calibration is
underway
•
Never write OADJ* registers if CAL_BG and CAL_BGOS
are set
•
If CAL_OS = 1 and CAL_BGOS=0, only read OADJ*
registers if FG_DONE = 1
•
If CAL_BG = 1 and CAL_BGOS=1, only read OADJ*
register if CAL_STOPPED = 1
7.6.1.5.31 Offset Filtering Control 0 Register (address = 0x097) [reset = 0x00]
Figure 133. Offset Filtering Control 0 Register (OSFILT0)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
DC_RESTORE
R/W
Table 96. OSFILT0 Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
DC_RESTORE
R/W
0
When set, the offset filtering feature (enabled by CAL_OSFILT)
filters only the offset mismatch across ADC banks and does not
remove the frequency content near DC. When cleared, the
feature filters all offsets from all banks, thus filtering all DC
content in the signal; see the Offset Filtering section.
0
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7.6.1.5.32 Offset Filtering Control 1 Register (address = 0x098) [reset = 0x33]
Figure 134. Offset Filtering Control 1 Register (OSFILT1)
7
6
5
4
3
2
OSFILT_BW
R/W-0011
1
0
OSFILT_SOAK
R/W-0011
Table 97. OSFILT1 Field Descriptions
106
Bit
Field
Type
Reset
Description
7-4
OSFILT_BW
R/W
0011
This field adjusts the IIR filter bandwidth for the offset filtering
feature (enabled by CAL_OSFILT). More bandwidth suppresses
more flicker noise from the ADCs and reduces the offset spurs.
Less bandwidth minimizes the impact of the filters on the
mission mode signal.
OSFILT_BW: IIR coefficient: –3-dB bandwidth (single sided)
0: Reserved
1: 2-10 : 609e-9 × FDEVCLK
2: 2-11 : 305e-9 × FDEVCLK
3: 2-12 : 152e-9 × FDEVCLK
4: 2-13 : 76e-9 × FDEVCLK
5: 2-14 : 38e-9 × FDEVCLK
6-15: Reserved
3-0
OSFILT_SOAK
R/W
0011
This field adjusts the IIR soak time for the offset filtering feature.
This field applies when offset filtering and background calibration
are both enabled. This field determines how long the IIR filter is
allowed to settle when first connected to an ADC after the ADC
is calibrated. After the soak time completes, the ADC is placed
online using the IIR filter. Set OSFILT_SOAK = OSFILT_BW.
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7.6.1.6 ADC Bank Registers (0x100 to 0x15F)
Table 98. ADC Bank Registers
ADDRESS
RESET
ACRONYM
0x100-0x101
Undefined
RESERVED
RESERVED
REGISTER NAME
0x102
Undefined
B0_TIME_0
Timing Adjustment for Bank 0 (0°
Clock) Register
0x103
Undefined
B0_TIME_90
Timing Adjustment for Bank 0 (–90°
Clock) Register
0x104-0x111
Undefined
RESERVED
RESERVED
0x112
Undefined
B1_TIME_0
Timing Adjustment for Bank 1 (0°
Clock) Register
0x113
Undefined
B1_TIME_90
Timing Adjustment for Bank 1 (–90°
Clock) Register
0x114-0x121
Undefined
RESERVED
RESERVED
0x122
Undefined
B2_TIME_0
Timing Adjustment for Bank 2 (0°
Clock) Register
0x123
Undefined
B2_TIME_90
Timing Adjustment for Bank 2 (–90°
Clock) Register
0x124-0x131
Undefined
RESERVED
RESERVED
0x132
Undefined
B3_TIME_0
Timing Adjustment for Bank 3 (0°
Clock) Register
0x133
Undefined
B3_TIME_90
Timing Adjustment for Bank 3 (–90°
Clock) Register
0x134-0x141
Undefined
RESERVED
RESERVED
0x142
Undefined
B4_TIME_0
Timing Adjustment for Bank 4 (0°
Clock) Register
0x143
Undefined
B4_TIME_90
Timing Adjustment for Bank 4 (–90°
Clock) Register
0x144-0x151
Undefined
RESERVED
RESERVED
0x152
Undefined
B5_TIME_0
Timing Adjustment for Bank 5 (0°
Clock) Register
0x153
Undefined
B5_TIME_90
Timing Adjustment for Bank 5 (–90°
Clock) Register
0x154-0x15F
Undefined
RESERVED
RESERVED
SECTION
—
Timing Adjustment for Bank 0 (0° Clock) Register
(address = 0x102) [reset = Undefined]
Timing Adjustment for Bank 0 (–90° Clock) Register
(address = 0x103) [reset = Undefined]
—
Timing Adjustment for Bank 1 (0° Clock) Register
(address = 0x112) [reset = Undefined]
Timing Adjustment for Bank 1 (–90° Clock) Register
(address = 0x113) [reset = Undefined]
—
Timing Adjustment for Bank 2 (0° Clock) Register
(address = 0x122) [reset = Undefined]
Timing Adjustment for Bank 2 (–90° Clock) Register
(address = 0x123) [reset = Undefined]
—
Timing Adjustment for Bank 3 (0° Clock) Register
(address = 0x132) [reset = Undefined]
Timing Adjustment for Bank 3 (–90° Clock) Register
(address = 0x133) [reset = Undefined]
—
Timing Adjustment for Bank 4 (0° Clock) Register
(address = 0x142) [reset = Undefined]
Timing Adjustment for Bank 4 (–90° Clock) Register
(address = 0x143) [reset = Undefined]
—
Timing Adjustment for Bank 5 (0° Clock) Register
(address = 0x152) [reset = Undefined]
Timing Adjustment for Bank 5 (–90° Clock) Register
(address = 0x153) [reset = Undefined]
—
7.6.1.6.1 Timing Adjustment for Bank 0 (0° Clock) Register (address = 0x102) [reset = Undefined]
Figure 135. Timing Adjustment for Bank 0 (0° Clock) Register (B0_TIME_0)
7
6
5
4
3
2
1
0
B0_TIME_0
R/W
Table 99. B0_TIME_0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B0_TIME_0
R/W
Undefined
Time adjustment for bank 0 (applied when the ADC is configured
for 0° clock phase). After reset, the factory-trimmed value can be
read and adjusted as required.
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7.6.1.6.2 Timing Adjustment for Bank 0 (–90° Clock) Register (address = 0x103) [reset = Undefined]
Figure 136. Timing Adjustment for Bank 0 (–90° Clock) Register (B0_TIME_90)
7
6
5
4
3
2
1
0
B0_TIME_90
R/W
Table 100. B0_TIME_90 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B0_TIME_90
R/W
Undefined
Time adjustment for bank 0 (applied when the ADC is configured
for –90° clock phase). After reset, the factory-trimmed value can
be read and adjusted as required.
7.6.1.6.3 Timing Adjustment for Bank 1 (0° Clock) Register (address = 0x112) [reset = Undefined]
Figure 137. Timing Adjustment for Bank 1 (0° Clock) Register (B1_TIME_0)
7
6
5
4
3
2
1
0
B1_TIME_0
R/W
Table 101. B1_TIME_0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B1_TIME_0
R/W
Undefined
Time adjustment for bank 1 (applied when the ADC is configured
for 0° clock phase). After reset, the factory-trimmed value can be
read and adjusted as required.
7.6.1.6.4 Timing Adjustment for Bank 1 (–90° Clock) Register (address = 0x113) [reset = Undefined]
Figure 138. Timing Adjustment for Bank 1 (–90° Clock) Register (B1_TIME_90)
7
6
5
4
3
2
1
0
B1_TIME_90
R/W
Table 102. B1_TIME_90 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B1_TIME_90
R/W
Undefined
Time adjustment for bank 1 (applied when the ADC is configured
for –90° clock phase). After reset, the factory-trimmed value can
be read and adjusted as required.
7.6.1.6.5 Timing Adjustment for Bank 2 (0° Clock) Register (address = 0x122) [reset = Undefined]
Figure 139. Timing Adjustment for Bank 2 (0° Clock) Register (B2_TIME_0)
7
6
5
4
3
2
1
0
B2_TIME_0
R/W
Table 103. B2_TIME_0 Field Descriptions
108
Bit
Field
Type
Reset
Description
7-0
B2_TIME_0
R/W
Undefined
Time adjustment for bank 2 (applied when the ADC is configured
for 0° clock phase). After reset, the factory-trimmed value can be
read and adjusted as required.
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7.6.1.6.6 Timing Adjustment for Bank 2 (–90° Clock) Register (address = 0x123) [reset = Undefined]
Figure 140. Timing Adjustment for Bank 2 (–90° Clock) Register (B2_TIME_90)
7
6
5
4
3
2
1
0
B2_TIME_90
R/W
Table 104. B2_TIME_90 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B2_TIME_90
R/W
Undefined
Time adjustment for bank 2 (applied when the ADC is configured
for –90° clock phase). After reset, the factory-trimmed value can
be read and adjusted as required.
7.6.1.6.7 Timing Adjustment for Bank 3 (0° Clock) Register (address = 0x132) [reset = Undefined]
Figure 141. Timing Adjustment for Bank 3 (0° Clock) Register (B3_TIME_0)
7
6
5
4
3
2
1
0
B3_TIME_0
R/W
Table 105. B3_TIME_0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B3_TIME_0
R/W
Undefined
Time adjustment for bank 3 (applied when the ADC is configured
for 0° clock phase). After reset, the factory-trimmed value can be
read and adjusted as required.
7.6.1.6.8 Timing Adjustment for Bank 3 (–90° Clock) Register (address = 0x133) [reset = Undefined]
Figure 142. Timing Adjustment for Bank 3 (–90° Clock) Register (B3_TIME_90)
7
6
5
4
3
2
1
0
B3_TIME_90
R/W
Table 106. B3_TIME_90 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B3_TIME_90
R/W
Undefined
Time adjustment for bank 3 (applied when the ADC is configured
for –90° clock phase). After reset, the factory-trimmed value can
be read and adjusted as required.
7.6.1.6.9 Timing Adjustment for Bank 4 (0° Clock) Register (address = 0x142) [reset = Undefined]
Figure 143. Timing Adjustment for Bank 4 (0° Clock) Register (B4_TIME_0)
7
6
5
4
3
2
1
0
B4_TIME_0
R/W
Table 107. B4_TIME_0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B4_TIME_0
R/W
Undefined
Time adjustment for bank 4 (applied when the ADC is configured
for 0° clock phase). After reset, the factory-trimmed value can be
read and adjusted as required.
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7.6.1.6.10 Timing Adjustment for Bank 4 (–90° Clock) Register (address = 0x143) [reset = Undefined]
Figure 144. Timing Adjustment for Bank 4 (–90° Clock) Register (B4_TIME_90)
7
6
5
4
3
2
1
0
B4_TIME_90
R/W
Table 108. B4_TIME_90 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B4_TIME_90
R/W
Undefined
Time adjustment for bank 4 (applied when the ADC is configured
for –90° clock phase). After reset, the factory-trimmed value can
be read and adjusted as required.
7.6.1.6.11 Timing Adjustment for Bank 5 (0° Clock) Register (address = 0x152) [reset = Undefined]
Figure 145. Timing Adjustment for Bank 5 (0° Clock) Register (B5_TIME_0)
7
6
5
4
3
2
1
0
B5_TIME_0
R/W
Table 109. B5_TIME_0 Field Descriptions
Bit
Field
Type
Reset
Description
7-0
B5_TIME_0
R/W
Undefined
Time adjustment for bank 5 (applied when the ADC is configured
for 0° clock phase). After reset, the factory-trimmed value can be
read and adjusted as required.
7.6.1.6.12 Timing Adjustment for Bank 5 (–90° Clock) Register (address = 0x153) [reset = Undefined]
Figure 146. Timing Adjustment for Bank 5 (–90° Clock) Register (B5_TIME_90)
7
6
5
4
3
2
1
0
B5_TIME_90
R/W
Table 110. B5_TIME_90 Field Descriptions
110
Bit
Field
Type
Reset
Description
7-0
B5_TIME_90
R/W
Undefined
Time adjustment for bank 5 (applied when the ADC is configured
for –90° clock phase). After reset, the factory-trimmed value can
be read and adjusted as required.
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7.6.1.7 LSB Control Registers (0x160 to 0x1FF)
Table 111. LSB Control Registers
ADDRESS
RESET
ACRONYM
0x160
0x00
ENC_LSB
0x161-0x1FF
Undefined
RESERVED
REGISTER NAME
SECTION
LSB Control Bit Output Register
LSB Control Bit Output Register (address = 0x160) [reset
= 0x00]
RESERVED
—
7.6.1.7.1 LSB Control Bit Output Register (address = 0x160) [reset = 0x00]
Figure 147. LSB Control Bit Output Register (ENC_LSB)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
TIMESTAMP_EN
R/W-0
Table 112. ENC_LSB Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
TIMESTAMP_EN
R/W
0
When set, the transport layer transmits the timestamp signal on
the LSB of the output samples. Only supported in decimate-by-1
(DDC bypass) modes. TIMESTAMP_EN has priority over
CAL_STATE_EN. TMSTP_RECV_EN must also be set high
when using timestamp. The latency of the timestamp signal
(through the entire device) matches the latency of the analog
ADC inputs.
In 8-bit modes, the control bit is placed on the LSB of the 8-bit
samples (leaving 7 bits of sample data). If the device is
configured for 12-bit data, the control bit is placed on the LSB of
the 12-bit data (leaving 11 bits of sample data).
The control bit enabled by this register is never advertised in the
ILA (the CS field is 0 in the ILA).
0
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7.6.1.8 JESD204B Registers (0x200 to 0x20F)
Table 113. JESD204B Registers
ADDRESS
RESET
ACRONYM
0x200
0x01
JESD_EN
0x201
0x02
JMODE
0x202
0x1F
KM1
0x203
0x01
JSYNC_N
0x204
0x02
0x205
REGISTER NAME
JESD204B Enable Register
SECTION
JESD204B Enable Register (address = 0x200) [reset =
0x01]
JESD204B Mode Register
JESD204B Mode Register (address = 0x201) [reset =
0x02]
JESD204B K Parameter Register
JESD204B K Parameter Register (address = 0x202)
[reset = 0x1F]
JESD204B Manual SYNC Request
Register
JESD204B Manual SYNC Request Register (address =
0x203) [reset = 0x01]
JCTRL
JESD204B Control Register
JESD204B Control Register (address = 0x204) [reset =
0x02]
0x00
JTEST
JESD204B Test Pattern Control
Register
0x206
0x00
DID
0x207
0x00
FCHAR
0x208
Undefined
JESD_STATUS
0x209
0x00
PD_CH
0x20A
0x00
JEXTRA_A
JESD204B Extra Lane Enable (Link
A)
JESD204B Extra Lane Enable (Link A) Register (address
= 0x20A) [reset = 0x00]
0x20B
0x00
JEXTRA_B
JESD204B Extra Lane Enable (Link
B)
JESD204B Extra Lane Enable (Link B) Register (address
= 0x20B) [reset = 0x00]
0x20C-0x20F
Undefined
RESERVED
RESERVED
JESD204B DID Parameter Register
JESD204B Frame Character
Register
JESD204B Test Pattern Control Register (address =
0x205) [reset = 0x00]
JESD204B DID Parameter Register (address = 0x206)
[reset = 0x00]
JESD204B Frame Character Register (address = 0x207)
[reset = 0x00]
JESD204B, System Status Register
JESD204B, System Status Register (address = 0x208)
[reset = Undefined]
JESD204B Channel Power-Down
JESD204B Channel Power-Down Register (address =
0x209) [reset = 0x00]
—
7.6.1.8.1 JESD204B Enable Register (address = 0x200) [reset = 0x01]
Figure 148. JESD204B Enable Register (JESD_EN)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
JESD_EN
R/W-1
Table 114. JESD_EN Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
JESD_EN
R/W
1
0 : Disables JESD204B interface
1 : Enables JESD204B interface
Before altering other JESD204B registers, JESD_EN must be
cleared. When JESD_EN is 0, the block is held in reset and the
serializers are powered down. The clocks are gated off to save
power. The LMFC counter is also held in reset, so SYSREF
does not align the LMFC.
Always set CAL_EN before setting JESD_EN.
Always clear JESD_EN before clearing CAL_EN.
0
112
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7.6.1.8.2 JESD204B Mode Register (address = 0x201) [reset = 0x02]
Figure 149. JESD204B Mode Register (JMODE)
7
6
RESERVED
R/W-000
5
4
3
2
JMODE
R/W-0001 0
1
0
Table 115. JMODE Field Descriptions
Bit
Field
Type
Reset
Description
7-5
RESERVED
R/W
000
RESERVED
4-0
JMODE
R/W
0001 0
Specify the JESD204B output mode (including DDC decimation
factor).
Only change this register when JESD_EN = 0 and CAL_EN = 0.
7.6.1.8.3 JESD204B K Parameter Register (address = 0x202) [reset = 0x1F]
Figure 150. JESD204B K Parameter Register (KM1)
7
6
RESERVED
R/W-000
5
4
3
2
KM1
R/W-1111 1
1
0
Table 116. KM1 Field Descriptions
Bit
Field
Type
Reset
Description
7-5
RESERVED
R/W
000
RESERVED
4-0
KM1
R/W
1111 1
K is the number of frames per multiframe and this register must
be programmed as K-1. Depending on the JMODE setting, there
are constraints on the legal values of K. (default: KM1 = 31, K =
32).
Only change this register when JESD_EN is 0.
7.6.1.8.4 JESD204B Manual SYNC Request Register (address = 0x203) [reset = 0x01]
Figure 151. JESD204B Manual SYNC Request Register (JSYNC_N)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
JSYNC_N
R/W-1
Table 117. JSYNC_N Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
JSYNC_N
R/W
1
Set this bit to 0 to request JESD204B synchronization
(equivalent to the SYNCSE pin being asserted). For normal
operation, leave this bit set to 1.
The JSYNC_N register can always generate a synchronization
request, regardless of the SYNC_SEL register. However, if the
selected sync pin is stuck low, the synchronization request
cannot be de-asserted unless SYNC_SEL = 2 is programmed.
0
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7.6.1.8.5 JESD204B Control Register (address = 0x204) [reset = 0x02]
Figure 152. JESD204B Control Register (JCTRL)
7
6
5
4
3
RESERVED
R/W-0000
2
SYNC_SEL
R/W-00
1
SFORMAT
R/W-1
0
SCR
R/W-0
Table 118. JCTRL Field Descriptions
Bit
Field
Type
Reset
Description
7-4
RESERVED
R/W
0000
RESERVED
3-2
SYNC_SEL
R/W
00
0: Use the SYNCSE input for the SYNC~ function (default)
1: Use the TMSTP± differential input for the SYNC~ function;
TMSTP_RECV_EN must also be set
2: Do not use any sync input signal (use software SYNC~
through JSYNC_N)
1
SFORMAT
R/W
1
Output sample format for JESD204B samples.
0: Offset binary
1: Signed 2’s complement (default)
0
SCR
R/W
0
0: Scrambler disabled (default)
1: Scrambler enabled
Only change this register when JESD_EN is 0.
7.6.1.8.6 JESD204B Test Pattern Control Register (address = 0x205) [reset = 0x00]
Figure 153. JESD204B Test Pattern Control Register (JTEST)
7
6
5
4
3
2
RESERVED
R/W-0000
1
0
JTEST
R/W-0000
Table 119. JTEST Field Descriptions
114
Bit
Field
Type
Reset
Description
7-4
RESERVED
R/W
0000
RESERVED
3-0
JTEST
R/W
0000
0: Test mode disabled; normal operation (default)
1: PRBS7 test mode
2: PRBS15 test mode
3: PRBS23 test mode
4: Ramp test mode
5: Transport layer test mode
6: D21.5 test mode
7: K28.5 test mode
8: Repeated ILA test mode
9: Modified RPAT test mode
10: Serial outputs held low
11: Serial outputs held high
12–15: Reserved
Only change this register when JESD_EN is 0.
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7.6.1.8.7 JESD204B DID Parameter Register (address = 0x206) [reset = 0x00]
Figure 154. JESD204B DID Parameter Register (DID)
7
6
5
4
3
2
1
0
DID
R/W-0000 0000
Table 120. DID Field Descriptions
Bit
Field
Type
Reset
7-0
DID
R/W
0000 0000 Specifies the device ID (DID) value that is transmitted during the
second multiframe of the JESD204B ILA. Link A transmits DID,
and link B transmits DID+1. Bit 0 is ignored and always returns 0
(if an odd number is programmed, that number is decremented
to an even number).
Only change this register when JESD_EN is 0.
Description
7.6.1.8.8 JESD204B Frame Character Register (address = 0x207) [reset = 0x00]
Figure 155. JESD204B Frame Character Register (FCHAR)
7
6
5
4
3
RESERVED
R/W-0000 00
2
1
0
FCHAR
R/W-00
Table 121. FCHAR Field Descriptions
Bit
Field
Type
Reset
Description
7-2
RESERVED
R/W
0000 00
RESERVED
1-0
FCHAR
R/W
00
Specify which comma character is used to denote end-of-frame.
This character is transmitted opportunistically (see the Frame
and Multiframe Monitoring section).
0: Use K28.7 (default, JESD204B compliant)
1: Use K28.1 (not JESD204B compliant)
2: Use K28.5 (not JESD204B compliant)
3: Reserved
When using a JESD204B receiver, always use FCHAR = 0.
When using a general-purpose 8b, 10b receiver, the K28.7
character may cause issues. When K28.7 is combined with
certain data characters, a false, misaligned comma character
can result, and some receivers realign to the false comma. To
avoid this condition, program FCHAR to 1 or 2.
Only change this register when JESD_EN is 0.
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7.6.1.8.9 JESD204B, System Status Register (address = 0x208) [reset = Undefined]
Figure 156. JESD204B, System Status Register (JESD_STATUS)
7
RESERVED
R
6
LINK_UP
R
5
SYNC_STATUS
R
4
REALIGNED
R/W
3
ALIGNED
R/W
2
PLL_LOCKED
R
1
0
RESERVED
R
Table 122. JESD_STATUS Field Descriptions
Bit
Field
Type
Reset
Description
7
RESERVED
R
Undefined
RESERVED
6
LINK_UP
R
Undefined
When set, this bit indicates that the JESD204B link is up.
5
SYNC_STATUS
R
Undefined
Returns the state of the JESD204B SYNC~ signal.
0: SYNC~ asserted
1: SYNC~ de-asserted
4
REALIGNED
R/W
Undefined
When high, this bit indicates that an internal digital clock, frame
clock, or multiframe (LMFC) clock phase was realigned by
SYSREF. Write a 1 to clear this bit.
3
ALIGNED
R/W
Undefined
When high, this bit indicates that the multiframe (LMFC) clock
phase has been established by SYSREF. The first SYSREF
event after enabling the JESD204B encoder will set this bit.
Write a 1 to clear this bit.
2
PLL_LOCKED
R
Undefined
When high, this bit indicates that the PLL is locked.
RESERVED
R
Undefined
RESERVED
1-0
7.6.1.8.10 JESD204B Channel Power-Down Register (address = 0x209) [reset = 0x00]
Figure 157. JESD204B Channel Power-Down Register (PD_CH)
7
6
5
4
3
2
RESERVED
R/W-0000 00
1
PD_BCH
R/W-0
0
PD_ACH
R/W-0
Table 123. PD_CH Field Descriptions
116
Bit
Field
Type
Reset
Description
7-2
RESERVED
R/W
0000 00
RESERVED
1
PD_BCH
R/W
0
When set, the B ADC channel is powered down. The digital
channels that are bound to the B ADC channel are also powered
down (see the digital channel binding register).
Important notes:
Set JESD_EN = 0 before changing PD_CH.
To power-down both ADC channels, use MODE.
If both channels are powered down, then the entire JESD204B
subsystem (including the PLL and LMFC) are powered down
If the selected JESD204B mode transmits A and B data on link
A, and the B digital channel is disabled, link A remains
operational, but the B-channel samples are undefined.
0
PD_ACH
R/W
0
When set, the A ADC channel is powered down. The digital
channels that are bound to the A ADC channel are also powered
down (digital channel binding register).
Important notes:
Set JESD_EN = 0 before changing PD_CH.
To power-down both ADC channels, use MODE.
If both channels are powered down, then the entire JESD204B
subsystem (including the PLL and LMFC) are powered down
If the selected JESD204B mode transmits A and B data on link
A, and the B digital channel is disabled, link A remains
operational, but the B-channel samples are undefined.
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7.6.1.8.11 JESD204B Extra Lane Enable (Link A) Register (address = 0x20A) [reset = 0x00]
Figure 158. JESD204B Extra Lane Enable (Link A) Register (JEXTRA_A)
7
6
5
4
EXTRA_LANE_A
R/W-0000 000
3
2
1
0
EXTRA_SER_A
R/W-0
Table 124. JESD204B Extra Lane Enable (Link A) Field Descriptions
Bit
Field
Type
Reset
Description
7-1
EXTRA_LANE_A
R/W
0000 000
Program these register bits to enable extra lanes (even if the
selected JMODE does not require the lanes to be enabled).
EXTRA_LANE_A(n) enables An (n = 1 to 7). This register
enables the link layer clocks for the affected lanes. To also
enable the extra serializes set EXTRA_SER_A = 1.
0
EXTRA_SER_A
R/W
0
0: Only the link layer clocks for extra lanes are enabled.
1: Serializers for extra lanes are also enabled. Use this mode to
transmit data from the extra lanes.
Important notes:
Only change this register when JESD_EN = 0.
The bit-rate and mode of the extra lanes are set by the JMODE
and JTEST parameters.
This register does not override the PD_CH register, so ensure
that the link is enabled to use this feature.
To enable serializer n, the lower number lanes 0 to n-1 must
also be enabled, otherwise serializer n does not receive a clock.
7.6.1.8.12 JESD204B Extra Lane Enable (Link B) Register (address = 0x20B) [reset = 0x00]
Figure 159. JESD204B Extra Lane Enable (Link B) Register (JEXTRA_B)
7
6
5
4
EXTRA_LANE_B
R/W-0000 000
3
2
1
0
EXTRA_SER_B
R/W-0
Table 125. JESD204B Extra Lane Enable (Link B) Field Descriptions
Bit
Field
Type
Reset
Description
7-1
EXTRA_LANE_B
R/W
0000 000
Program these register bits to enable extra lanes (even if the
selected JMODE does not require the lanes to be enabled).
EXTRA_LANE_B(n) enables Bn (n = 1 to 7). This register
enables the link layer clocks for the affected lanes. To also
enable the extra serializes set EXTRA_SER_B = 1.
0
EXTRA_SER_B
R/W
0
0: Only the link layer clocks for extra lanes are enabled.
1: Serializers for extra lanes are also enabled. Use this mode to
transmit data from the extra lanes.
Important notes:
Only change this register when JESD_EN = 0.
The bit-rate and mode of the extra lanes are set by the JMODE
and JTEST parameters.
This register does not override the PD_CH register, so ensure
that the link is enabled to use this feature.
To enable serializer n, the lower number lanes 0 to n-1 must
also be enabled, otherwise serializer n does not receive a clock.
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7.6.1.9 Digital Down Converter Registers (0x210-0x2AF)
Table 126. Digital Down Converter and Overrange Registers
ADDRESS
RESET
ACRONYM
REGISTER NAME
0x210
0x00
DDC_CFG
DDC Configuration Register
0x211
0xF2
OVR_T0
Overrange Threshold 0 Register
Overrange Threshold 0 Register (address = 0x211) [reset
= 0xF2]
0x212
0xAB
OVR_T1
Overrange Threshold 1 Register
Overrange Threshold 1 Register (address = 0x212) [reset
= 0xAB]
0x213
0x07
OVR_CFG
Overrange Configuration Register
Overrange Configuration Register (address = 0x213)
[reset = 0x07]
0x214
0x00
CMODE
DDC Configuration Preset Mode
Register
DDC Configuration Preset Mode Register (address =
0x214) [reset = 0x00]
0x215
0x00
CSEL
DDC Configuration Preset Select
Register
DDC Configuration Preset Select Register (address =
0x215) [reset = 0x00]
0x216
0x02
DIG_BIND
Digital Channel Binding Register
Digital Channel Binding Register (address = 0x216) [reset
= 0x02]
0x217-0x218
0x0000
NCO_RDIV
Rational NCO Reference Divisor
Register
Rational NCO Reference Divisor Register (address =
0x217 to 0x218) [reset = 0x0000]
0x219
0x02
NCO_SYNC
NCO Synchronization Register
0x21A-0x21F
Undefined
RESERVED
RESERVED
0x220-0x223
0xC0000000
FREQA0
0x224-0x225
0x0000
PHASEA0
0x226-0x227
Undefined
RESERVED
0x228-0x22B
0xC0000000
FREQA1
0x22C-0x22D
0x0000
PHASEA1
0x22E-0x22F
Undefined
RESERVED
0x230-0x233
0xC0000000
FREQA2
0x234-0x235
0x0000
PHASEA2
0x236-0x237
Undefined
RESERVED
0x238-0x23B
0xC0000000
FREQA3
0x23C-0x23D
0x0000
PHASEA3
0x23E-0x23F
Undefined
RESERVED
0x240-0x243
0xC0000000
FREQB0
0x244-0x245
0x0000
PHASEB0
0x246-0x247
Undefined
RESERVED
0x248-0x24B
0xC0000000
FREQB1
0x24C-0x24D
0x0000
PHASEB1
0x24E-0x24F
Undefined
RESERVED
0x250-0x253
0xC0000000
FREQB2
0x254-0x255
0x0000
PHASEB2
0x256-0x257
Undefined
RESERVED
0x258-0x25B
0xC0000000
FREQB3
0x25C-0x25D
0x0000
PHASEB3
118
NCO Frequency (DDC A Preset 0)
NCO Phase (DDC A Preset 0)
RESERVED
NCO Frequency (DDC A Preset 1)
NCO Phase (DDC A Preset 1)
RESERVED
NCO Frequency (DDC A Preset 2)
NCO Phase (DDC A Preset 2)
RESERVED
NCO Frequency (DDC A Preset 3)
NCO Phase (DDC A Preset 3)
RESERVED
NCO Frequency (DDC B Preset 0)
NCO Phase (DDC B Preset 0)
RESERVED
NCO Frequency (DDC B Preset 1)
NCO Phase (DDC B Preset 1)
RESERVED
NCO Frequency (DDC B Preset 2)
NCO Phase (DDC B Preset 2)
RESERVED
NCO Frequency (DDC B Preset 3)
NCO Phase (DDC B Preset 3)
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SECTION
DDC Configuration Register (address = 0x210) [reset =
0x00]
NCO Synchronization Register (address = 0x219) [reset =
0x02]
—
NCO Frequency (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
NCO Phase (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
—
NCO Frequency (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
NCO Phase (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
—
NCO Frequency (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
NCO Phase (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
—
NCO Frequency (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
NCO Phase (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
—
NCO Frequency (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
NCO Phase (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
—
NCO Frequency (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
NCO Phase (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
—
NCO Frequency (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
NCO Phase (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
—
NCO Frequency (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
NCO Phase (DDC A or DDC B and Preset x) Register
(address = see Table 126) [reset = see Table 126]
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Table 126. Digital Down Converter and Overrange Registers (continued)
ADDRESS
RESET
ACRONYM
0x25E-0x296
Undefined
RESERVED
0x297
Undefined
SPIN_ID
0x298-0x2AF
Undefined
RESERVED
REGISTER NAME
SECTION
RESERVED
—
Spin Identification Value
Spin Identification Register (address = 0x297) [reset =
Undefined]
RESERVED
—
7.6.1.9.1 DDC Configuration Register (address = 0x210) [reset = 0x00]
Figure 160. DDC Configuration Register (DDC_CFG)
7
6
5
RESERVED
R/W-0000
4
3
D4_AP87
R/W-0
2
D2_HIGH_PASS
R/W-0
1
INVERT_SPECTRUM
R/W-0
0
BOOST
R/W-0
Table 127. DDC_CFG Field Descriptions
Bit
Field
Type
Reset
Description
7-4
RESERVED
R/W
0000
RESERVED
3
D4_AP87
R/W
0
0: Decimate-by-4 mode uses 80% alias protection, > 80-dB
suppression
1: Decimate-by-4 mode uses 87.5% alias protection, > 60-dB
suppression
2
D2_HIGH_PASS
R/W
0
0: Decimate-by-2 mode uses a low-pass filter
1: Decimate-by-2 mode uses a high-pass filter. Decimating the
high-pass signal causes spectral inversion. This inversion can
be undone by setting INVERT_SPECTRUM.
1
INVERT_SPECTRUM
R/W
0
0: No inversion applied to output spectrum
1: Output spectrum is inverted
This register only applies when the DDC is enabled and is
producing a real output (not complex). The spectrum is inverted
by mixing the signal with FSOUT / 2 (for example, invert all odd
samples).
0
BOOST
R/W
0
DDC gain control. Only applies to DDC modes with complex
decimation.
0: Final filter has 0-dB gain (default)
1: Final filter has 6.02-dB gain. Only use this setting when
certain that the negative image of the input signal is filtered out
by the DDC, otherwise digital clipping may occur.
7.6.1.9.2 Overrange Threshold 0 Register (address = 0x211) [reset = 0xF2]
Figure 161. Overrange Threshold 0 Register (OVR_T0)
7
6
5
4
3
2
1
0
OVR_T0
R/W-1111 0010
Table 128. OVR_T0 Field Descriptions
Bit
Field
Type
Reset
7-0
OVR_T0
R/W
1111 0010 Overrange threshold 0. This parameter defines the absolute
sample level that causes control bit 0 to be set. The detection
level in dBFS (peak) is:
20log10(OVR_T0 / 256)
Default: 0xF2 = 242 → –0.5 dBFS.
Description
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7.6.1.9.3 Overrange Threshold 1 Register (address = 0x212) [reset = 0xAB]
Figure 162. Overrange Threshold 1 Register (OVR_T1)
7
6
5
4
3
2
1
0
OVR_T1
R/W-1010 1011
Table 129. OVR_T1 Field Descriptions
Bit
Field
Type
Reset
7-0
OVR_T1
R/W
1010 1011 Overrange threshold 1. This parameter defines the absolute
sample level that causes control bit 1 to be set. The detection
level in dBFS (peak) is:
20log10(OVR_T1 / 256)
Default: 0xAB = 171 → –3.5 dBFS.
Description
7.6.1.9.4 Overrange Configuration Register (address = 0x213) [reset = 0x07]
Figure 163. Overrange Configuration Register (OVR_CFG)
7
6
5
4
3
OVR_EN
R/W-0
RESERVED
R/W-0000
2
1
OVR_N
R/W-111
0
Table 130. OVR_CFG Field Descriptions
(1)
120
Bit
Field
Type
Reset
Description
7-4
RESERVED
R/W
0000 0
RESERVED
3
OVR_EN
R/W
0
Enables overrange status output pins when set high. The ORA0,
ORA1, ORB0, and ORB1 outputs are held low when OVR_EN is
set low. This register only effects the overrange output pins
(ORxx) and not the overrange status embedded in the data
samples.
2-0
OVR_N (1)
R/W
111
Program this register to adjust the pulse extension for the ORA0,
ORA1 and ORB0, ORB1 outputs. The minimum pulse duration
of the overrange outputs is 8 × 2OVR_N DEVCLK cycles.
Incrementing this field doubles the monitoring period.
Changing the OVR_N setting while JESD_EN=1 may cause the phase of the monitoring period to change.
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7.6.1.9.5 DDC Configuration Preset Mode Register (address = 0x214) [reset = 0x00]
Figure 164. DDC Configuration Preset Mode Register (CMODE)
7
6
5
4
3
2
1
RESERVED
R/W-0000 00
0
CMODE
R/W-00
Table 131. CMODE Field Descriptions
Bit
Field
Type
Reset
Description
7-2
RESERVED
R/W
0000 00
RESERVED
1-0
CMODE
R/W
00
The NCO frequency and phase for DDC A are set by the
FREQAx and PHASEAx registers and the NCO frequency and
phase for DDC B are set by the FREQBx and PHASEBx
registers, where x is the configuration preset (0 through 3).
0: Use CSEL register to select the active NCO configuration
preset for DDC A and DDC B
1: Use NCOA[1:0] pins to select the active NCO configuration
preset for DDC A and use NCOB[1:0] pins to select the active
NCO configuration preset for DDC B
2: Use NCOA[1:0] pins to select the active NCO configuration
preset for both DDC A and DDC B
3: Reserved
7.6.1.9.6 DDC Configuration Preset Select Register (address = 0x215) [reset = 0x00]
Figure 165. DDC Configuration Preset Select Register (CSEL)
7
6
5
4
3
RESERVED
R/W-0000
2
CSELB
R/W-00
1
0
CSELA
R/W-00
Table 132. CSEL Field Descriptions
Bit
Field
Type
Reset
Description
7-4
RESERVED
R/W
0000
RESERVED
3-2
CSELB
R/W
00
When CMODE = 0, this register is used to select the active NCO
configuration preset for DDC B.
1-0
CSELA
R/W
00
When CMODE = 0, this register is used to select the active NCO
configuration preset for DDC A.
Example: If CSELA = 0, then FREQA0 and PHASEA0 are the
active settings. If CSELA = 1, then FREQA1 and PHASEA1 are
the active settings.
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7.6.1.9.7 Digital Channel Binding Register (address = 0x216) [reset = 0x02]
Figure 166. Digital Channel Binding Register (DIG_BIND)
7
6
5
4
3
2
RESERVED
R/W-0000 00
1
DIG_BIND_B
R/W-1
0
DIG_BIND_A
R/W-0
Table 133. DIG_BIND Field Descriptions
Bit
Field
Type
Reset
Description
7-2
RESERVED
R/W
0000 00
RESERVED
1
DIG_BIND_B
R/W
0
Digital channel B input select:
0: Digital channel B receives data from ADC channel A
1: Digital channel B receives data from ADC channel B (default)
0
DIG_BIND_A
R/W
0
Digital channel A input select:
0: Digital channel A receives data from ADC channel A (default)
1: Digital channel A receives data from ADC channel B
When using single-channel mode, always use the default setting
for DIG_BIND or the device does not work.
Set JESD_EN = 0 and CAL_EN = 0 before changing DIG_BIND.
The DIG_BIND setting is combined with PD_ACH, PD_BCH to
determine if a digital channel is powered down. Each digital
channel (and link) is powered down when the ADC channel it is
bound to is powered down (by PD_ACH, PD_BCH).
7.6.1.9.8 Rational NCO Reference Divisor Register (address = 0x217 to 0x218) [reset = 0x0000]
Figure 167. Rational NCO Reference Divisor Register (NCO_RDIV)
15
14
13
12
11
NCO_RDIV[15:8]
R/W-0000 0000
10
9
8
7
6
5
4
2
1
0
3
NCO_RDIV[7:0]
R/W-0000 0000
Table 134. NCO_RDIV Field Descriptions
Bit
15-0
122
Field
Type
Reset
Description
NCO_RDIV
R/W
0x0000h
Sometimes the 32-bit NCO frequency word does not provide the
desired frequency step size and can only approximate the
desired frequency. This condition results in a frequency error.
Use this register to eliminate the frequency error. This register is
used for all configuration presets; see the Rational NCO
Frequency Setting Mode section.
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7.6.1.9.9 NCO Synchronization Register (address = 0x219) [reset = 0x02]
Figure 168. NCO Synchronization Register (NCO_SYNC)
7
6
5
4
RESERVED
R/W-0000 00
3
2
1
NCO_SYNC_ILA
R/W-1
0
NCO_SYNC_NEXT
R/W-0
Table 135. NCO_SYNC Field Descriptions
Bit
Field
Type
Reset
Description
7-2
RESERVED
R/W
0000 00
RESERVED
1
NCO_SYNC_ILA
R/W
0
When this bit is set, the NCO phase is initialized by the LMFC
edge that starts the ILA sequence (default).
0
NCO_SYNC_NEXT
R/W
0
After writing a 0 and then a 1 to this bit, the next SYSREF rising
edge initializes the NCO phase. When the NCO phase is
initialized by SYSREF, the NCO does not reinitialize on future
SYSREF edges unless a 0 and a 1 is written to this bit again.
Follow these steps to align the NCO in multiple parts:
•
Ensure the device is powered up, JESD_EN is set, and the
device clock is running.
•
Ensure that SYSREF is disabled (not toggling).
•
Program NCO_SYNC_ILA = 0 on all devices.
•
Write NCO_SYNC_NEXT = 0 on all devices.
•
Write NCO_SYNC_NEXT = 1 on all devices. NCO sync is
armed.
•
Instruct the SYSREF source to generate 1 or more SYSREF
pulses.
•
All devices initialize their NCO using the first SYSREF rising
edge.
7.6.1.9.10 NCO Frequency (DDC A or DDC B and Preset x) Register (address = see Table 126) [reset = see
Table 126]
Figure 169. NCO Frequency (DDC A or DDC B and Preset x) Register (FREQAx or FREQBx)
31
30
29
28
27
FREQAx[31:24] or FREQBx[31:24]
R/W-0xC0
26
25
24
23
22
21
20
19
FREQAx[23:16] or FREQBx[23:16]
R/W-0x00
18
17
16
15
14
13
12
11
FREQAx[15:8] or FREQBx[15:8]
R/W-0x00
10
9
8
7
6
5
4
3
FREQAx[7:0] or FREQBx[7:0]
R/W-0x00
2
1
0
Table 136. FREQAx or FREQBx Field Descriptions
Bit
31-0
Field
Type
Reset
Description
FREQAx or FREQBx
R/W
See
Table 126
Changing this register after the JESD204B interface is running
results in non-deterministic NCO phase. If deterministic phase is
required, the JESD204B interface must be re-initialized after
changing this register. This register can be interpreted as signed
or unsigned; see the Basic NCO Frequency Setting Mode
section.
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7.6.1.9.11 NCO Phase (DDC A or DDC B and Preset x) Register (address = see Table 126) [reset = see Table 126]
Figure 170. NCO Phase (DDC A or DDC B and Preset x) Register (PHASEAx or PHASEBx)
15
14
13
12
11
PHASEAx[15:8] or PHASEBx[15:8]
R/W-0x00
10
9
8
7
6
5
4
3
PHASEAx[7:0] or PHASEBx[7:0]
R/W-0x00
2
1
0
Table 137. PHASEAx or PHASEBx Field Descriptions
Bit
15-0
Field
Type
Reset
Description
PHASEAx or PHASEBx
R/W
See
Table 126
This value is MSB-justified into a 32-bit field and then added to
the phase accumulator. This register can be interpreted as
signed or unsigned; see the NCO Phase Offset Setting section.
7.6.1.10 Spin Identification Register (address = 0x297) [reset = Undefined]
Figure 171. Spin Identification Register (SPIN_ID)
7
6
RESERVED
R-000
5
4
3
2
SPIN_ID
R
1
0
Table 138. SPIN_ID Field Descriptions
124
Bit
Field
Type
Reset
Description
7-5
RESERVED
R
000
RESERVED
4-0
SPIN_ID
R
1
Spin identification value.
1 : ADC12DJ2700
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7.6.2 SYSREF Calibration Registers (0x2B0 to 0x2BF)
Table 139. SYSREF Calibration Registers
ADDRESS
RESET
ACRONYM
REGISTER NAME
SECTION
0x2B0
0x00
SRC_EN
SYSREF Calibration Enable Register
SYSREF Calibration Enable Register (address = 0x2B0)
[reset = 0x00]
0x2B1
0x05
SRC_CFG
0x2B2-0x2B4
Undefined
SRC_STATUS
0x2B5-0x2B7
0x00
TAD
0x2B8
0x00
0x2B9-0x2BF
Undefined
SYSREF Calibration Configuration
Register
SYSREF Calibration Configuration Register (address =
0x2B1) [reset = 0x05]
SYSREF Calibration Status
SYSREF Calibration Status Register (address = 0x2B2 to
0x2B4) [reset = Undefined]
DEVCLK Aperture Delay Adjustment
Register
DEVCLK Aperture Delay Adjustment Register (address =
0x2B5 to 0x2B7) [reset = 0x000000]
TAD_RAMP
DEVCLK Timing Adjust Ramp
Control Register
DEVCLK Timing Adjust Ramp Control Register (address
= 0x2B8) [reset = 0x00]
RESERVED
RESERVED
—
7.6.2.1 SYSREF Calibration Enable Register (address = 0x2B0) [reset = 0x00]
Figure 172. SYSREF Calibration Enable Register (SRC_EN)
7
6
5
4
RESERVED
R/W-0000 000
3
2
1
0
SRC_EN
R/W-0
Table 140. SRC_EN Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R/W
0000 000
RESERVED
SRC_EN
R/W
0
0: SYSREF calibration disabled; use the TAD register to
manually control the TAD[16:0] output and adjust the DEVCLK
delay (default)
1: SYSREF calibration enabled; the DEVCLK delay is
automatically calibrated; the TAD register is ignored
A 0-to-1 transition on SRC_EN starts the SYSREF calibration
sequence. Program SRC_CFG before setting SRC_EN. Ensure
that ADC calibration is not currently running before setting
SRC_EN.
0
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7.6.2.2 SYSREF Calibration Configuration Register (address = 0x2B1) [reset = 0x05]
Figure 173. SYSREF Calibration Configuration Register (SRC_CFG)
7
6
5
4
3
RESERVED
R/W-0000
2
1
SRC_AVG
R/W-01
0
SRC_HDUR
R/W-01
Table 141. SRC_CFG Field Descriptions
Bit
Field
Type
Reset
Description
7-4
RESERVED
R/W
0000 00
RESERVED
3-2
SRC_AVG
R/W
01
Specifies the amount of averaging used for SYSREF calibration.
Larger values increase calibration time and reduce the variance
of the calibrated value.
0: 4 averages
1: 16 averages
2: 64 averages
3: 256 averages
1-0
SRC_HDUR
R/W
01
Specifies the duration of each high-speed accumulation for
SYSREF Calibration. If the SYSREF period exceeds the
supported value, the calibration fails. Larger values increase
calibration time and support longer SYSREF periods. For a
given SYSREF period, larger values also reduce the variance of
the calibrated value.
0: 4 cycles per accumulation, max SYSREF period of 85
DEVCLK cycles
1: 16 cycles per accumulation, max SYSREF period of 1100
DEVCLK cycles
2: 64 cycles per accumulation, max SYSREF period of 5200
DEVCLK cycles
3: 256 cycles per accumulation, max SYSREF period of 21580
DEVCLK cycles
Max duration of SYSREF calibration is bounded by:
TSYSREFCAL (in DEVCLK cycles) = 256 × 19 × 4(SRC_AVG +
SRC_HDUR + 2)
7.6.2.3 SYSREF Calibration Status Register (address = 0x2B2 to 0x2B4) [reset = Undefined]
Figure 174. SYSREF Calibration Status Register (SRC_STATUS)
23
22
21
20
19
18
17
SRC_DONE
R
16
SRC_TAD[16]
R
RESERVED
R
15
14
13
12
11
SRC_TAD[15:8]
R
10
9
8
7
6
5
4
2
1
0
3
SRC_TAD[7:0]
R
Table 142. SRC_STATUS Field Descriptions
Field
Type
Reset
Description
23-18
Bit
RESERVED
R
Undefined
RESERVED
17
SRC_DONE
R
Undefined
This bit returns a 1 when SRC_EN = 1 and SYSREF calibration
is complete.
SRC_TAD
R
Undefined
This field returns the value for TAD[16:0] computed by the
SYSREF calibration. This field is only valid if SRC_DONE = 1.
16-0
126
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7.6.2.4 DEVCLK Aperture Delay Adjustment Register (address = 0x2B5 to 0x2B7) [reset = 0x000000]
Figure 175. DEVCLK Aperture Delay Adjustment Register (TAD)
23
22
21
15
14
7
6
20
RESERVED
R/W-0000 000
19
18
17
16
TAD_INV
R/W-0
13
12
11
TAD_COARSE
R/W-0000 0000
10
9
8
5
4
2
1
0
3
TAD_FINE
R/W-0000 0000
Table 143. TAD Field Descriptions
Bit
Field
Type
Reset
Description
RESERVED
R/W
0000 000
RESERVED
TAD_INV
R/W
0
Invert DEVCLK by setting this bit equal to 1.
15-8
TAD_COARSE
R/W
0000 0000 This register controls the DEVCLK aperture delay adjustment
when SRC_EN = 0. Use this register to manually control the
DEVCLK aperture delay when SYSREF calibration is disabled. If
ADC calibration or JESD204B is running, TI recommends
gradually increasing or decreasing this value (1 code at a time)
to avoid clock glitches. See the Switching Characteristics table
for TAD_COARSE resolution.
7-0
TAD_FINE
R/W
0000 0000 See the Switching Characteristics table for TAD_FINE
resolution.
23-17
16
7.6.2.5 DEVCLK Timing Adjust Ramp Control Register (address = 0x2B8) [reset = 0x00]
Figure 176. DEVCLK Timing Adjust Ramp Control Register (TAD_RAMP)
7
6
5
4
RESERVED
R/W-0000 00
3
2
1
TAD_RAMP_RATE
R/W-0
0
TAD_RAMP_EN
R/W-0
Table 144. TAD_RAMP Field Descriptions
Bit
Field
Type
Reset
Description
7-2
RESERVED
R/W
0000 00
RESERVED
1
TAD_RAMP_RATE
R/W
0
Specifies the ramp rate for the TAD[15:8] output when the
TAD[15:8] register is written when TAD_RAMP_EN = 1.
0: TAD[15:8] ramps up or down one code per 256 DEVCLK
cycles.
1: TAD[15:8] ramps up or down 4 codes per 256 DEVCLK
cycles.
0
TAD_RAMP_EN
R/W
0
TAD ramp enable. Set this bit if coarse TAD adjustments are
desired to ramp up or down instead of changing abruptly.
0: After writing the TAD[15:8] register the aperture delay is
updated within 1024 DEVCLK cycles
1: After writing the TAD[15:8] register the aperture delay ramps
up or down until the aperture delay matches the TAD[15:8]
register
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7.6.3 Alarm Registers (0x2C0 to 0x2C2)
Table 145. Alarm Registers
ADDRESS
RESET
ACRONYM
0x2C0
Undefined
ALARM
REGISTER NAME
0x2C1
0x1F
ALM_STATUS
Alarm Status Register
Alarm Status Register (address = 0x2C1) [reset = 0x1F]
0x2C2
0x1F
ALM_MASK
Alarm Mask Register
Alarm Mask Register (address = 0x2C2) [reset = 0x1F]
Alarm Interrupt Status Register
SECTION
Alarm Interrupt Register (address = 0x2C0) [reset =
Undefined]
7.6.3.1 Alarm Interrupt Register (address = 0x2C0) [reset = Undefined]
Figure 177. Alarm Interrupt Register (ALARM)
7
6
5
4
RESERVED
R
3
2
1
0
ALARM
R
Table 146. ALARM Field Descriptions
Bit
Field
Type
Reset
Description
7-1
RESERVED
R
Undefined
RESERVED
ALARM
R
Undefined
This bit returns a 1 whenever any alarm occurs that is
unmasked in the ALM_STATUS register. Use ALM_MASK to
mask (disable) individual alarms. CAL_STATUS_SEL can be
used to drive the ALARM bit onto the CALSTAT output pin to
provide a hardware alarm interrupt signal.
0
7.6.3.2 Alarm Status Register (address = 0x2C1) [reset = 0x1F]
Figure 178. Alarm Status Register (ALM_STATUS)
7
6
RESERVED
R/W-000
5
4
PLL_ALM
R/W-1
3
LINK_ALM
R/W-1
2
REALIGNED_ALM
R/W-1
1
NCO_ALM
R/W-1
0
CLK_ALM
R/W-1
Table 147. ALM_STATUS Field Descriptions
128
Bit
Field
Type
Reset
Description
7-5
RESERVED
R/W
000
RESERVED
4
PLL_ALM
R/W
1
PLL lock lost alarm. This bit is set whenever the PLL is not
locked. Write a 1 to clear this bit.
3
LINK_ALM
R/W
1
Link alarm. This bit is set whenever the JESD204B link is
enabled, but is not in the DATA_ENC state. Write a 1 to clear
this bit.
2
REALIGNED_ALM
R/W
1
Realigned alarm. This bit is set whenever SYSREF causes the
internal clocks (including the LMFC) to be realigned. Write a 1 to
clear this bit.
1
NCO_ALM
R/W
1
NCO alarm. This bit can be used to detect an upset to the NCO
phase. This bit is set when any of the following occur:
•
The NCOs are disabled (JESD_EN = 0)
•
The NCOs are synchronized (intentionally or unintentionally)
•
Any phase accumulators in channel A do not match channel
B
Write a 1 to clear this bit.
0
CLK_ALM
R/W
1
Clock alarm. This bit can be used to detect an upset to the
digital block and JESD204B clocks. This bit is set whenever the
internal clock dividers for the A and B channels do not match.
Write a 1 to clear this bit.
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7.6.3.3 Alarm Mask Register (address = 0x2C2) [reset = 0x1F]
Figure 179. Alarm Mask Register (ALM_MASK)
7
6
5
4
3
RESERVED
MASK_PLL_ALM
MASK_LINK_ALM
R/W-000
R/W-1
R/W-1
2
MASK_REALIGNED_
ALM
R/W-1
1
0
MASK_NCO_ALM
MASK_CLK_ALM
R/W-1
R/W-1
Table 148. ALM_MASK Field Descriptions
Bit
Field
Type
Reset
Description
7-5
RESERVED
R/W
000
RESERVED
4
MASK_PLL_ALM
R/W
1
When set, PLL_ALM is masked and does not impact the ALARM
register bit.
3
MASK_LINK_ALM
R/W
1
When set, LINK_ALM is masked and does not impact the
ALARM register bit.
2
MASK_REALIGNED_ALM
R/W
1
When set, REALIGNED_ALM is masked and does not impact
the ALARM register bit.
1
MASK_NCO_ALM
R/W
1
When set, NCO_ALM is masked and does not impact the
ALARM register bit.
0
MASK_CLK_ALM
R/W
1
When set, CLK_ALM is masked and does not impact the
ALARM register bit.
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The ADC12DJ2700 can be used in a wide range of applications including radar, satellite communications, test
equipment (communications testers and oscilloscopes), and software-defined radios (SDRs). The wide input
bandwidth enables direct RF sampling to at least 8 GHz and the high sampling rate allows signal bandwidths of
greater than 2 GHz. The Typical Applications section describes one configuration that meets the needs of a
number of these applications.
8.2 Typical Applications
8.2.1 Wideband RF Sampling Receiver
LNA
LNA
Up to 16 Lanes
JESD204B
Antialias BPF
ADC A
JESD
204B
DDC
SYNC~
LNA
LNA
Antialias BPF
ADC B
JESD
204B
DDC
FPGA or ASIC
Clocking
Subsystem
User Control
Logic
SPI
LMK04832
Device Clock
÷
SYSREF
N÷
R÷
PFD
10-MHz
Reference
÷
Device Clock
÷
÷
SYSREF
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Figure 180. Typical Configuration for Wideband RF Sampling
8.2.1.1 Design Requirements
8.2.1.1.1 Input Signal Path
Use appropriate band-limiting filters to reject unwanted frequencies in the input signal path.
A 1:2 balun transformer is needed to convert the 50-Ω, single-ended signal to 100-Ω differential for input to the
ADC. The balun outputs can be either AC-coupled, or directly connected to the ADC differential inputs, which are
terminated internally to GND.
130
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Typical Applications (continued)
Drivers must be selected to provide any needed signal gain and that have the necessary bandwidth capabilities.
Baluns must be selected to cover the needed frequency range, have a 1:2 impedance ratio, and have acceptable
gain and phase balance over the frequency range of interest. Table 149 lists a number of recommended baluns
for different frequency ranges.
Table 149. Recommended Baluns
(1)
PART NUMBER
MANUFACTURER (1)
MINIMUM FREQUENCY (MHz)
MAXIMUM FREQUENCY (MHz)
BAL-0009SMG
Marki Microwave
0.5
9000
BAL-0208SMG
Marki Microwave
2000
8000
TCM2-43X+
Mini-Circuits
10
4000
TCM2-33WX+
Mini-Circuits
10
3000
B0430J50100AHF
Anaren
400
3000
See the Third-Party Products Disclaimer section.
8.2.1.1.2 Clocking
The ADC12DJ2700 clock inputs must be AC-coupled to the device to ensure rated performance. The clock
source must have extremely low jitter (integrated phase noise) to enable rated performance. Recommended
clock synthesizers include the LMX2594, LMX2592, and LMX2582.
The JESD204B data converter system (ADC plus FPGA) requires additional SYSREF and device clocks. The
LMK04828, LMK04826, and LMK04821 devices are suitable to generate these clocks. Depending on the ADC
clock frequency and jitter requirements, this device may also be used as the system clock synthesizer or as a
device clock and SYSREF distribution device when multiple ADC12DJ2700 devices are used in a system.
8.2.1.2 Detailed Design Procedure
Certain component values used in conjunction with the ADC12DJ2700 must be calculated based on system
parameters. Those items are covered in this section.
8.2.1.2.1 Calculating Values of AC-Coupling Capacitors
AC-coupling capacitors are used in the input CLK± and JESD204B output data pairs. The capacitor values must
be large enough to address the lowest frequency signals of interest, but not so large as to cause excessively
long startup biasing times, or unwanted parasitic inductance.
The minimum capacitor value can be calculated based on the lowest frequency signal that is transferred through
the capacitor. Given a 50-Ω single-ended clock or data path impedance, good practice is to set the capacitor
impedance to be
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