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DAC5682Z
SLLS853F – AUGUST 2007 – REVISED JANUARY 2015
DAC5682Z 16-Bit, 1.0 GSPS 2x-4x Interpolating Dual-Channel
Digital-to-Analog Converter (DAC)
1 Features
3 Description
•
•
•
The DAC5682Z is a dual-channel 16-bit 1.0 GSPS
DAC with wideband LVDS data input, integrated
2x/4x interpolation filters, onboard clock multiplier,
and internal voltage reference. The DAC5682Z offers
superior linearity, noise, crosstalk, and PLL phase
noise performance.
1
•
•
•
•
•
•
•
16-Bit Digital-to-Analog Converter (DAC)
1.0 GSPS Update Rate
16-Bit Wideband Input LVDS Data Bus
– 8 Sample Input FIFO
– Interleaved I/Q Data for Dual-DAC Mode
High Performance
– 73-dBc ACLR WCDMA TM1 at 180 MHz
2x-32x Clock Multiplying PLL/VCO
2x or 4x Interpolation Filters
– Stopband Transition 0.4 to 0.6 Fdata
– Filters Configurable in Either Low-Pass or
High-Pass Mode
– Allows Selection of Higher Order Image
Fs/4 Coarse Mixer
On-Chip 1.2-V Reference
Differential Scalable Output: 2 to 20 mA
Package: 64-Pin 9-mm × 9-mm QFN
2 Applications
•
•
•
•
•
The DAC5682Z integrates a wideband LVDS port
with on-chip termination. Full-rate input data can be
transferred to a single DAC channel, or half-rate and
1/4-rate input data can be interpolated by onboard 2x
or 4x FIR filters. Each interpolation FIR is
configurable in either low-pass or high-pass mode,
allowing selection of a higher order output spectral
image. An on-chip delay lock loop (DLL) simplifies
LVDS interfacing by providing skew control for the
LVDS input data clock.
Device Information(1)
PART NUMBER
DAC5682Z
PACKAGE
VQFN (64)
BODY SIZE (NOM)
9.00 mm × 9.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
3-Carrier WCDMA TM1 With a Gap
Cellular Base Stations
Broadband Wireless Access (BWA)
WiMAX 802.16
Fixed Wireless Backhaul
Cable Modem Termination System (CMTS)
-20 Carrier Power: -15.20 dBm,
ACLR (5 MHz): 71.18 dB,
-30 ACLR (10 MHz): 72.26 dB,
Fdata = 491.52 MSPS,
IF = 184.32 MHz,
-40 x2 Interpolation
PLL Off
Power - dBm
-50
-60
-70
-80
-90
-100
-110
-120
160 165 170 175 180 185 190 195 200 205 210
f - Frequency - MHz
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.
DAC5682Z
SLLS853F – AUGUST 2007 – REVISED JANUARY 2015
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Description (continued).........................................
Pin Configuration and Functions .........................
Specifications.........................................................
7.1
7.2
7.3
7.4
7.5
7.6
7.7
7.8
8
1
1
1
2
4
5
7
Absolute Maximum Ratings ...................................... 7
ESD Ratings.............................................................. 7
Recommended Operating Conditions....................... 7
Thermal Information .................................................. 8
Electrical Characteristics — DC Specification ......... 8
Electrical Characteristics — AC Specification ....... 10
Electrical Characteristics (Digital Specifications) ... 11
Typical Characteristics ............................................ 15
Detailed Description ............................................ 19
8.1 Overview ................................................................. 19
8.2 Functional Block Diagram ....................................... 19
8.3 Feature Description................................................. 20
8.4 Device Functional Modes........................................ 33
8.5 Programming........................................................... 36
8.6 Register Maps ......................................................... 39
9
Application and Implementation ........................ 49
9.1
9.2
9.3
9.4
Application Information............................................
Typical Application ..................................................
System Examples ...................................................
Initialization Set Up .................................................
49
49
51
55
10 Power Supply Recommendations ..................... 55
11 Layout................................................................... 56
11.1 Layout Guidelines ................................................. 56
11.2 Layout Example .................................................... 56
12 Device and Documentation Support ................. 57
12.1
12.2
12.3
12.4
Device Support......................................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
57
57
57
58
13 Mechanical, Packaging, and Orderable
Information ........................................................... 58
4 Revision History
Changes from Revision E (August 2012) to Revision F
•
Page
Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation
section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and
Mechanical, Packaging, and Orderable Information section .................................................................................................. 1
Changes from Revision D (February 2011) to Revision E
Page
•
Changed the Revision to E, August 2012 .............................................................................................................................. 1
•
Changed the graphic entity of Figure 30 for clarification...................................................................................................... 23
•
Changed the first paragraph of ANALOG CURRENT OUTPUTS section for clarification. .................................................. 29
Changes from Revision C (November 2008) to Revision D
Page
•
Changed "defined by individual control bits in registers CONFIG1, CONFIG5 and CONFIG6." to "defined by
individual control bits in registers CONFIG1 and CONFIG5." .............................................................................................. 26
•
Changed wording in second sentence of RECOMMENED....PROCEDURE section from CONFIG5 clkdiv_sync_dis
and FIFO_sync_dis bits as well to CONFIG5 clkdiv_sync_dis as well ............................................................................ 35
•
Deleted list items in first and second ordered list in RECOMMENED....PROCEDURE section ......................................... 35
•
Changed CONFIG5 Bit4 from "FIFO_ sync_dis" to "Reserved" in Register Map ................................................................ 39
•
Changed CONFIG6 Bit 7 from "Hold_ sync_dis" to "Reserved" in Register Map ................................................................ 39
•
Deleted - unless-----CONFIG5 register. in FIFO_offset(2:0): on page 21 ............................................................................ 40
•
Changed Bit 4 in CONFIG5 table from FIFO_sync_dis to Reserved ................................................................................... 43
•
Changed "FIFO_sync_sis: Disables the FIFO offset sync........ CONFIG1 register" to "Reserved (Bit 4): Set to 0 for
proper operation." ................................................................................................................................................................. 43
•
Changed Hold_sync _dis to Reserved ................................................................................................................................. 43
•
Changed from Hold_sync_dis: When set, disables the sync to the FIFO .....control bit in CONFIG5." to " Reserved
(Bit 7): Set to 0 for proper operation." .................................................................................................................................. 43
2
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SLLS853F – AUGUST 2007 – REVISED JANUARY 2015
Changes from Revision B (April 2008) to Revision C
Page
•
Changed Thermal Conductivity θJA (still air) from 22 to 20 .................................................................................................... 8
•
Changed θJC from 7 to 0.2...................................................................................................................................................... 8
•
Changed θJP from 0.2 to 3.5 ................................................................................................................................................... 8
•
Changed DC Spec - Analog Output test condition from "without internal reference" ............................................................ 8
•
Changed DC spec. REFERENCE INPUT, Small signal bandwidth conditions...................................................................... 9
•
Changed Power Supply DVDD MIN from 1.71 to 1.7 and MAX from 2.15 to 1.9 .................................................................. 9
•
Changed Power Supply CLKVDD MIN from 1.71 to 1.7 and MAX from 2.15 to 1.9.............................................................. 9
•
Added "DC tested" to PSRR spec........................................................................................................................................ 10
•
Added Digital latency spec. .................................................................................................................................................. 10
•
Added Power-up time spec .................................................................................................................................................. 10
•
Added D[15:0]P/N................................................................................................................................................................. 11
•
Changed VITH+ spec .............................................................................................................................................................. 11
•
Changed VITH– spec .............................................................................................................................................................. 11
•
Changed IIH and IIL spec from –40 MIN and +40 MAX to ±20 TYP...................................................................................... 12
•
Changed t(SCLK) term to t(SCLKL) for Low time of SCLK .......................................................................................................... 13
•
Changed Clock Input Differential voltage from 0.5V to 0.4V MIN and added footnote ........................................................ 13
•
Added explanatory paragraph for LVDS Inputs; prior to Figure 33 ..................................................................................... 25
•
Changed Figure 34 waveform label VA,B callout .................................................................................................................. 26
•
Added explanatory paragraph for Figure 35......................................................................................................................... 26
•
Changed calculation for C2 Designing the PLL Loop Filter................................................................................................ 31
•
Added URL link to calculator file. ......................................................................................................................................... 32
•
Changed last sentence of Dual-Channel Real Upconversion paragraph............................................................................. 33
•
Added modes to Dual-Channel Real Upconversion Options ............................................................................................... 33
•
Added references to CDCE62005 (3 places) ...................................................................................................................... 33
•
Added Multi-DAC Synchronization Procedure...................................................................................................................... 35
•
Changed Recommended DAC Startup Sequence ............................................................................................................... 55
Changes from Revision A (September 2007) to Revision B
Page
•
Changed tr(IOUT) spec. output rise time 10% to 90% typical value from 2 ns to 220 ps........................................................ 10
•
Changed tf(IOUT) spec. output fall time 10% to 90% typical value from 2 ns to 220 ps ......................................................... 10
•
Changed ZT spec. internal termination from 100 Ω min, 120 Ω max; to 85 Ω min, 135 Ω max........................................... 12
•
Deleted temperature deratings for fDATA specifications......................................................................................................... 12
•
Added DLL operating frequency range specifications.......................................................................................................... 12
•
Changed In-Band SFDR vs IF, Figure 6 ............................................................................................................................. 15
•
Changed CAC values from 0.1 to 0.01μF, Figure 30............................................................................................................. 23
•
Changed capacitor values from 0.1 to 0.01μF, Figure 35 ................................................................................................... 26
Changes from Original (August 2007) to Revision A
•
Page
Changed from product preview to production data ................................................................................................................ 1
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DAC5682Z
SLLS853F – AUGUST 2007 – REVISED JANUARY 2015
www.ti.com
5 Description (continued)
The DAC5682Z allows both complex or real output. An optional Fs/4 coarse mixer in complex mode provides
coarse frequency upconversion and the dual DAC output produces a complex Hilbert Transform pair. An external
RF quadrature modulator then performs the final single sideband up-conversion. The interpolation filters and
complex coarse mixers efficiently provide frequency plan flexibility while enabling higher output DAC rates to
simplify image rejection filtering.
The DAC5682Z is characterized for operation over the industrial temperature range of –40°C to 85°C and is
available in a 64-pin QFN package. Other single-channel members of the family include the interpolating
DAC5681Z and the noninterpolating DAC5681.
4
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SLLS853F – AUGUST 2007 – REVISED JANUARY 2015
6 Pin Configuration and Functions
RESETB
AVDD
54
49
AVDD
DVDD
EXTIO
56
55
50
BIASJ
57
51
AVDD
EXTLO
IOUTA2
IOUTB2
60
59
IOUTA1
AVDD
IOUTB1
61
53
AVDD
62
52
DVDD
63
58
LPF
64
RGC Package
64 Pins
Top View
CLKVDD
1
48
SDENB
CLKIN
2
47
SCLK
CLKINC
3
46
SDIO
GND
4
45
SDO
SYNCP
5
44
VFUSE
SYNCN
D15P
6
43
D0N
7
42
D0P
41
D1N
40
D1P
D15N
8
IOVDD
9
DVDD
10
39
DVDD
D14P
11
38
D2N
D14N
12
37
D2P
D13P
13
36
D3N
D13N
14
35
D3P
D12P
15
34
D4N
D12N
16
33
D4P
31
D5P
32
30
D6N
D5N
28
29
D6P
27
D7P
D7N
25
26
DCLKP
DCLKN
23
24
D8P
D8N
21
20
D10N
22
19
D10P
D9P
18
D11N
D9N
17
D11P
DAC5682Z
Pin Functions
PIN
I/O
DESCRIPTION
NAME
NO.
AVDD
51, 54, 55,
59, 62
I
BIASJ
57
O
Full-scale output current bias. For 20-mA full-scale output current, connect a 960-Ω resistor to GND.
CLKIN
2
I
Positive external clock input with a self-bias of approximately CLKVDD/2. With the clock multiplier PLL
enabled, CLKIN provides lower frequency reference clock. If the PLL is disabled, CLKIN directly provides
clock for DAC up to 1 GHz.
CLKINC
3
I
Complementary external clock input. (See the CLKIN description)
CLKVDD
1
I
Internal clock buffer supply voltage. (1.8 V)
D[15..0]P
7, 11, 13,
15, 17, 19,
21, 23, 27,
29, 31, 33,
35, 37, 40,
42
I
LVDS positive input data bits 0 through 15. Each positive/negative LVDS pair has an internal 100 Ω
termination resistor. Order of bus can be reversed via rev_bus bit in CONFIG5 register. Data format relative
to DCLKP/N clock is Double Data Rate (DDR) with two data samples input per DCLKP/N clock. In dualchannel mode, data for the A-channel is input while DCLKP is high.
Analog supply voltage. (3.3 V)
D15P is most significant data bit (MSB) – pin 7
D0P is least significant data bit (LSB) – pin 42
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DAC5682Z
SLLS853F – AUGUST 2007 – REVISED JANUARY 2015
www.ti.com
Pin Functions (continued)
PIN
NAME
NO.
D[15..0]N
8, 12, 14,
16, 18, 20,
22, 24, 28,
30, 32, 34,
36, 38, 41,
43
I/O
DESCRIPTION
LVDS negative input data bits 0 through 15. (See D[15:0]P description above)
D15N is most significant data bit (MSB) – pin 8
D0N is least significant data bit (LSB) – pin 43
I
25
I
LVDS positive input clock. Unlike the other LVDS inputs, the DCLKP/N pair is self-biased to approximately
DVDD/2 and does not have an internal termination resistor in order to optimize operation of the DLL circuit.
See DLL Operation. For proper external termination, connect a 100 Ω resistor across LVDS clock source
lines followed by series 0.01 μF capacitors connected to each of DCLKP and DCLKN pins (see ). For best
performance, the resistor and capacitors should be placed as close as possible to these pins.
DCLKN
26
I
LVDS negative input clock. (See the DCLKP description)
DVDD
10, 39, 50,
63
I
EXTIO
56
Used as external reference input when internal reference is disabled (i.e., EXTLO connected to AVDD).
I/O Used as 1.2-V internal reference output when EXTLO = GND, requires a 0.1 μF decoupling capacitor to
AGND when used as reference output.
EXTLO
58
O
Connect to GND for internal reference, or AVDD for external reference.
4, Thermal
Pad
I
Pin 4 and the Thermal Pad located on the bottom of the QFN package is ground for AVDD, DVDD and
IOVDD supplies.
IOUTA1
52
O
A-Channel DAC current output. An offset binary data pattern of 0x0000 at the DAC input results in a full
scale current sink and the least positive voltage on the IOUTA1 pin. Similarly, a 0xFFFF data input results in
a 0 mA current sink and the most positive voltage on the IOUTA1 pin. In single DAC mode, outputs appear
on the IOUTA1/A2 pair only.
IOUTA2
53
O
A-Channel DAC complementary current output. The IOUTA2 has the opposite behavior of the IOUTA1
described above. An input data value of 0x0000 results in a 0-mA sink and the most positive voltage on the
IOUTA2 pin.
IOUTB1
61
O
B-Channel DAC current output. See the IOUTA1 description above.
IOUTB2
60
O
B-Channel DAC complementary current output. See the IOUTA2 description above.
IOVDD
9
I
Digital I/O supply voltage (3.3 V) for pins RESETB, SCLK, SDENB, SDIO, SDO.
LPF
64
I
PLL loop filter connection. If not using the clock multiplying PLL, the LPF pin may be left open. Set both
PLL_bypass and PLL_sleep control bits for reduced power dissipation.
RESETB
49
I
Resets the chip when low. Internal pullup.
SCLK
47
I
Serial interface clock. Internal pulldown.
SDENB
48
I
Active low serial data enable, always an input to the DAC5682Z. Internal pullup.
SDIO
46
I/O
Bi-directional serial interface data in 3-pin mode (default). In 4-pin interface mode (CONFIG5 sif4), the SDIO
pin is an input only. Internal pulldown.
SDO
45
O
Uni-directional serial interface data in 4-pin mode (CONFIG5 sif4). The SDO pin is in high-impedance state
in 3-pin interface mode (default), but can optionally be used as a status output pin via CONFIG14
SDO_func_sel(2:0). Internal pulldown.
SYNCP
5
I
LVDS SYNC positive input data. The SYNCP/N LVDS pair has an internal 100 Ω termination resistor. By
default, the SYNCP/N input must be logic ‘1’ to enable a DAC analog output. See the LVDS SYNCP/N
Operation paragraph for a detailed description.
SYNCN
6
I
LVDS SYNC negative input data.
VFUSE
44
I
Digital supply voltage. (1.8 V) Connect to DVDD pins for normal operation. This supply pin is also used
for factory fuse programming.
DCLKP
GND
6
Digital supply voltage. (1.8 V)
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7 Specifications
7.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)
(1)
DVDD (2)
VFUSE
Supply voltage
(2)
MIN
MAX
UNIT
–0.5
2.3
V
–0.5
2.3
V
CLKVDD (2)
–0.5
2.3
V
AVDD (2)
–0.5
4
V
(2)
–0.5
4
V
AVDD to DVDD
–2
2.6
V
–0.5
0.5
V
–0.5
0.5
V
–0.5
DVDD +
0.5
V
DCLKP, DCLKN (2)
–0.3
2.1
V
(2)
–0.5
CLKVDD
+ 0.5
V
–0.5
IOVDD +
0.5
V
–0.5
AVDD +
0.5
V
–0.5
AVDD +
0.5
V
Peak input current (any input)
20
mA
Peak total input current (all inputs)
–30
mA
IOVDD
CLKVDD to DVDD
IOVDD to AVDD
D[15..0]P ,D[15..0]N, SYNCP, SYNCN
Supply voltage
CLKIN, CLKINC
SDO, SDIO, SCLK, SDENB, RESETB
IOUTA1/B1, IOUTA2/B2
(2)
(2)
(2)
LPF, EXTIO, EXTLO, BIASJ (2)
Operating free-air temperature, TA: DAC5682Z
–40
85
°C
Storage temperature, Tstg
–65
150
°C
(1)
(2)
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of these or any other conditions beyond those indicated under Recommended Operating Conditions is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
Measured with respect to GND.
7.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
Electrostatic discharge
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1)
±2000
Charged-device model (CDM), per JEDEC specification JESD22C101 (2)
±500
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.
7.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
UNIT
AVDD
3
3.3
3.6
V
DVDD
1.7
1.8
1.9
V
CLKVDD
1.7
1.8
1.9
V
3
3.3
3.6
V
0
20
20
mA
SUPPLIES
IOVDD
ANALOG OUTPUT
IOUTA1, IOUTA2, IOUTB1, IOUTB2
V IOUTA1, IOUTA2, IOUTB1, IOUTB2 Compliance voltage
AVDD-0.5
AVDD+0.5
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7
DAC5682Z
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www.ti.com
Recommended Operating Conditions (continued)
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
UNIT
1000
MHz
0.4
1
CLKVDD
CLOCK INPUT
CLKIN ECL/PECL Frequency
CLKIN Amplitude Differential
CLKIN Duty Cycle
V
50%
CLKIN common mode voltage
CLKDVDD
/2
V
DCLK LVDS Frequency
500
MHz
DIGITAL INPUTS
SYNC LVDS
1
1.2
1.4
V
D15..D0 LVDS
1
1.2
1.4
V
LVDS Common mode
1.2
LVDS Differential Swing
0.4
SCLK, SDIO, SDENB, SDO CMOS SPI
V
V
GND
IOVDD
V
7.4 Thermal Information
DAC5682Z
THERMAL METRIC (1)
QFN
UNIT
64 PINS
TJ
Maximum junction temperature
(2)
125
°C
Theta junction-to-ambient (still air)
22
Theta junction-to-ambient (150 lfm)
16
RθJC
Theta junction-to-case
0.2
°C/W
RθJP
Theta junction-to-pad
3.5
°C/W
RθJA
(1)
(2)
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
Air flow or heat sinking reduces θJA and may be required for sustained operation at 85° under maximum operating conditions.
7.5
Electrical Characteristics — DC Specification
over operating free-air temperature range , AVDD = 3.3 V, CLKVDD = 1.8 V, IOVDD = 3.3 V, DVDD = 1.8 V, IoutFS = 20 mA
(unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
Resolution
DC ACCURACY
TYP
MAX
16
UNIT
Bits
(1)
INL
Integral nonlinearity
DNL
Differential nonlinearity
1 LSB = IOUTFS/216
±4
LSB
±2
ANALOG OUTPUT
Course gain linearity
(1)
(2)
8
Offset error
Mid code offset
Gain error
With external reference
Gain error
With internal reference
Gain mismatch
With internal reference, dual DAC
±0.04
LSB
0.01
%FSR
1
%FSR
0.7
–2
%FSR
2
Minimum full scale output current (2)
2
Maximum full scale output current (2)
20
%FSR
mA
Measured differential across IOUTA1 and IOUTA2 or IOUTB1 and IOUTB2 with 25 Ω each to AVDD.
Nominal full-scale current, IoutFS, equals 16 × IBIAS current.
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Electrical Characteristics — DC Specification (continued)
over operating free-air temperature range , AVDD = 3.3 V, CLKVDD = 1.8 V, IOVDD = 3.3 V, DVDD = 1.8 V, IoutFS = 20 mA
(unless otherwise noted)
PARAMETER
Output Compliance range (3)
TEST CONDITIONS
IOUTFS = 20 mA
MIN
TYP
AVDD
–0.5V
Output resistance
Output capacitance
MAX
UNIT
AVDD
+ 0.5V
V
300
kΩ
5
pF
REFERENCE OUTPUT
Vref
Reference voltage
1.14
Reference output current (4)
1.2
1.26
V
100
nA
REFERENCE INPUT
VEXTIO
Input voltage range
0.1
Input resistance
Small signal bandwidth
1.25
V
1
CONFIG6: BiasLPF_A and BiasLPF_B = 0
95
CONFIG6: BiasLPF_A and BiasLPF_B = 1
472
Input capacitance
MΩ
kHz
100
pF
±1
ppm of
FSR/°C
TEMPERATURE COEFFICIENTS
Offset drift
Gain drift
With external reference
±15
With internal reference
±30
ppm of
FSR/°C
±8
ppm/°C
Reference voltage drift
POWER SUPPLY
Analog supply voltage, AVDD
3.0
3.3
3.6
V
Digital supply voltage, DVDD
1.7
1.8
1.9
V
Clock supply voltage, CLKVDD
1.7
1.8
1.9
V
I/O supply voltage, IOVDD
3.0
3.3
3.6
I(AVDD)
Analog supply current
I(DVDD)
Digital supply current
I(CLKVDD)
Clock supply current
I(IOVDD)
V
133
mA
455
mA
45
mA
IO supply current
12
mA
I(AVDD)
Sleep mode, AVDD supply current
1.0
mA
I(DVDD)
Sleep mode, DVDD supply current
1.5
mA
I(CLKVDD)
Sleep mode, CLKVDD supply
current
2.5
mA
I(IOVDD)
Sleep mode, IOVDD supply current
2.0
mA
(3)
(4)
Mode 4 (below)
Mode 6 (below)
The lower limit of the output compliance is determined by the CMOS process. Exceeding this limit may result in transistor breakdown,
resulting in reduced reliability of the DAC5682Z device. The upper limit of the output compliance is determined by the load resistors and
full-scale output current. Exceeding the upper limit adversely affects distortion performance and integral nonlinearity.
Use an external buffer amplifier with high impedance input to drive any external load.
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Electrical Characteristics — DC Specification (continued)
over operating free-air temperature range , AVDD = 3.3 V, CLKVDD = 1.8 V, IOVDD = 3.3 V, DVDD = 1.8 V, IoutFS = 20 mA
(unless otherwise noted)
PARAMETER
TEST CONDITIONS
AVDD + IOVDD current, 3.3 V
DVDD + CLKVDD current, 1.8 V
MIN
Mode 1: 2X2, PLL = OFF, CLKIN = 983.04 MHz
FDAC = 983.04 MHz, IF = 184.32 MHz
DACA and DACB ON, 4 carrier WCDMA
DVDD + CLKVDD current, 1.8 V
Power Dissipation
AVDD + IOVDD current, 3.3 V
DVDD + CLKVDD current, 1.8 V
Power Dissipation
P
AVDD + IOVDD current, 3.3 V
DVDD + CLKVDD current, 1.8 V
Power Dissipation
AVDD + IOVDD current, 3.3 V
DVDD + CLKVDD current, 1.8 V
Power Dissipation
AVDD + IOVDD current, 3.3 V
DVDD + CLKVDD current, 1.8 V
Mode 2: 2X2, PLL = ON (8X), CLKIN = 122.88
MHz
FDAC = 983.04 MHz, IF = 184.32 MHz
DACA and DACB ON, 4 carrier WCDMA
Mode 3: 2X4, CMIX0 = Fs/4, PLL = OFF, CLKIN =
983.04 MHz
FDAC = 983.04 MHz, IF = 215.04 MHz
DACA and DACB ON, 4 carrier WCDMA
Mode 4: 2X4, CMIX0 = Fs/4, PLL = ON (8X),
CLKIN = 122.88 MHz
FDAC = 983.04 MHz, IF = 215.04 MHz
DACA and DACB ON, 4 carrier WCDMA
Power supply rejection ratio
T
Operating range
450
mA
mW
145
mA
485
mA
1350
mW
135
mA
480
mA
1310
mW
145
mA
mA
1600
5
Mode 6: 2X4, PLL = OFF, CLKIN = OFF
FDAC = OFF, Digital Logic Disabled
DACA and DACB = SLEEP, Static Data Pattern
mW
mA
185
mA
350
mW
3.0
mA
4.0
17.0
DC tested
mA
505
Mode 5: 2X2, CMIX0 = Fs/4, PLL = OFF, CLKIN =
983.04 MHz
FDAC = 983.04 MHz, Digital Logic Disabled
DACA and DACB SLEEP, Static Data Pattern
UNIT
1255
1400
Power Dissipation
PSRR
MAX
135
Power Dissipation
AVDD + IOVDD current, 3.3 V
TYP
mA
30.0
mW
–0.2
0.2 %FSR/V
–40
85
°C
Electrical Characteristics — AC Specification (1)
7.6
Over recommended operating free-air temperature range, AVDD, IOVDD = 3.3 V, CLKVDD, DVDD = 1.8 V, IOUTFS = 20 mA,
4:1 transformer output termination, 50Ω doubly terminated load (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
ANALOG OUTPUT
fCLK
Maximum output update
rate
ts(DAC)
Output settling time to
0.1%
tpd
1000
Transition: Code 0x0000 to 0xFFFF
MSPS
10.4
ns
Output propagation delay
2.5
ns
tr(IOUT)
Output rise time 10% to
90%
220
ps
tf(IOUT)
Output fall time 90% to
10%
220
ps
Digital latency
Powerup time
No interpolation, PLL Off
78
x2 interpolation, PLL Off
163
x4 interpolation, PLL Off
308
DAC wake-up time
IOUT current settling to 1% of IOUTFS.
Measured from SDENB; Register 0x06, toggle Bit 4 from 1 to 0.
80
DAC sleep time
IOUT current settling to 1% of IOUTFS.
Measured from SDENB; Register 0x06, toggle Bit 4 from 0 to 1.
80
(1)
Measured single-ended into 50 Ω load.
10
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Electrical Characteristics — AC Specification(1) (continued)
Over recommended operating free-air temperature range, AVDD, IOVDD = 3.3 V, CLKVDD, DVDD = 1.8 V, IOUTFS = 20 mA,
4:1 transformer output termination, 50Ω doubly terminated load (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
AC PERFORMANCE
Spurious free dynamic
range
SFDR
SNR
Signal-to-noise ratio
Third-order two-tone
intermodulation
(each tone at –6 dBFS)
IMD3
Four-tone intermodulation
(each tone at –12 dBFS)
IMD
1X1, PLL off, CLKIN = 500 MHz, DACA on, IF = 5.1 MHz,
First Nyquist Zone < fDATA/2
81
2X2, PLL off, CLKIN = 1000 MHz, DACA and DACB on,
IF = 5.1 MHz, First Nyquist Zone < fDATA/2
80
2X2, PLL off, CLKIN = 1000 MHz, DACA and DACB on,
IF = 20.1 MHz, First Nyquist Zone < fDATA/2
77
2X2, PLL off, CLKIN = 500 MHZ, DACA and DACB on, Single
tone, 0 dBFS, IF = 20.1 MHz
75
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on, Single
tone, 0 dBFS, IF = 20.1 MHz
70
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on, Single
tone, 0 dBFS, IF = 70.1 MHz
66
2X4, PLL off, CLKIN = 1000 MHZ, DACA and DACB on, Single
tone, 0 dBFS, IF = 180 MHz
60
2X2 CMIX, PLL off, CLKIN = 1000 MHZ, DACA and DACB on,
Single tone, 0 dBFS, IF = 300.2 MHz
60
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on, Four
tone, each -12 dBFS, IF = 24.7, 24.9, 25.1 and 25.3 MHz
73
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on,
IF = 20.1 and 21.1 MHz
88
2X2, PLL off, CLKIN = 1000 MHZ, DACA and DACB on,
IF = 70.1 and 71.1 MHz
75
2X2 CMIX, PLL off, CLKIN = 1000 MHZ, DACA and DACB on,
IF = 150.1 and 151.1 MHz
67
2X2 CMIX, PLL off, CLKIN = 1000 MHz, DACA and DACB on,
fOUT = 298.4, 299.2, 300.8 and 301.6 MHz
64
dBc
Single carrier, baseband, 2X2, PLL off, CLKIN = 983.04 MHz,
DACA and DACB on
ACLR
(2)
Adjacent channel leakage
ratio
Noise floor
(2)
(3)
(3)
dBc
80
dBc
dBc
83
Single carrier, IF = 180 MHz, 2X2, PLL off,
CLKIN = 983.04 MHz, DACA and DACB on
73
Four carrier, IF = 180 MHz, 2X2 CMIX, PLL off,
CLKIN = 983.04 MHz, DACA and DACB on
68
Four carrier, IF = 275 MHz, 2X2 CMIX, PLL off,
CLKIN = 983.04 MHz, DACA and DACB on
66
50-MHz offset, 1-MHz BW, Single Carrier, baseband, 2X2, PLL
off, CLKIN = 983.04
93
50-MHz offset, 1-MHz BW, Four Carrier, baseband, 2X2, PLL off,
CLKIN = 983.04.
85
dBc
dBc
W-CDMA with 3.84 MHz BW, 5-MHz spacing, centered at IF. TESTMODEL 1, 10 ms
Carrier power measured in 3.84 MHz BW.
7.7
Electrical Characteristics (Digital Specifications)
over recommended operating free-air temperature range, AVDD, IOVDD = 3.3 V, CLKVDD, DVDD = 1.8 V.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
LVDS INTERFACE: D[15:0]P/N, SYNCP/N, DCLKP/N (1)
VA,B+
Logic high differential
input voltage threshold
VA,B–
Logic low differential input
voltage threshold
VCOM1
Input Common Mode
(1)
SYNCP/N, D[15:0]P/N only
175
mV
–175
mV
1.0
V
See LVDS Inputs for terminology.
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Electrical Characteristics (Digital Specifications) (continued)
over recommended operating free-air temperature range, AVDD, IOVDD = 3.3 V, CLKVDD, DVDD = 1.8 V.
PARAMETER
VCOM2
Input Common Mode
ZT
Internal termination
CL
LVDS Input capacitance
tS, tH
DCLK to Data
TEST CONDITIONS
DCLKP/N only
SYNCP/N, D[15:0]P/N only
DCLKP/N: 0 to 125 MHz (see Figure 43)
DLL Disabled, CONFIG5 DLL_bypass = 1,
CONFIG10 = '00000000'
DCLKP/N = 250 MHz
DLL Enabled,
CONFIG5
DLL_bypass = 0,
DDR format
DCLKP/N = 300 MHz
DCLKP/N = 350 MHz
DCLKP/N = 400 MHz
DCLKP/N = 450 MHz
DCLKP/N = 500 MHz
Input
data rate supported
fDATA
DLL Operating Frequency
(DCLKP/N Frequency)
MAX
85
110
Setup_min
1100
Hold_min
–600
Positive
1000
Negative
–1800
Positive
135
ps
–1300
Positive
600
Negative
–1000
Positive
450
Negative
–800
Positive
400
Negative
–700
Positive
300
Negative
–600
Positive
300
Negative
–500
Positive
350
Negative
–300
DLL Disabled, CONFIG5 DLL_bypass = 1, DDR format,
DCLKP frequency: 1'
(transition)
TXEnable=’1'
CMIX1
47t 76dB HBF
FIR1
x2
[Modes = LP, HP, Fs/4, -Fs/4]
CMIX0
FIR0
[Modes = LP, HP, Fs/8, -Fs/8]
47t 76dB HBF
x2
47t 76dB HBF
2
13
2
FIR1 Enable
100
SYNCP
16
16
8 Sample FIFO
D0N
DDR De-interleave
100
D0P
(x1 Bypass)
CM0 Mode
16
D15N
x2
FIR0 Enable
100
D15P
4
A-Offset
13
B
A
EXTLO
DACA_gain
Mode Control
CM1 Mode
DCLKN
PLL Enable
DLL Control
DAC Delay (0-3)
Delay Lock
Loop (DLL)
EXTIO
BIASJ
16bit
DAC
IOUTA1
16bit
DAC
IOUTB1
IOUTA2
IOUTB2
2
Delay Value
DCLKP
1.2V
Reference
FDAC/2
FDAC/4
B-Offset
CLKINC
FDAC
Clock
Distribution
4
DACB_gain
Sync & Control
SW_Sync
GND
(3.3V)
IOVDD
RESETB
SCLK
SDENB
SDO
SDIO
FIFO Sync Disable
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8.3 Feature Description
8.3.1 FIR Filters
Figure 24 shows the magnitude spectrum response for the identical 47-tap FIR0 and FIR1 filters. The transition
band is from 0.4 to 0.6 × FIN (the input data rate for the FIR filter) with 300 kΩ in parallel with an output
capacitance of 5 pF.
The external output resistors are referred to an external ground. The minimum output compliance at nodes
IOUT1 and IOUT2 is limited to AVDD – 0.5 V, determined by the CMOS process. Beyond this value, transistor
breakdown may occur resulting in reduced reliability of the DAC5682Z device. The maximum output compliance
voltage at nodes IOUT1 and IOUT2 equals AVDD + 0.5 V. Exceeding the minimum output compliance voltage
adversely affects distortion performance and integral non-linearity. The optimum distortion performance for a
single-ended or differential output is achieved when the maximum full-scale signal at IOUT1 and IOUT2 does not
exceed 0.5 V.
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AVDD
R LOAD
R LOAD
IOUT1
IOUT2
S(1)
S(N)
S(2)
S(2)C
S(1)C
S(N)C
...
Figure 38. Equivalent Analog Current Output
The DAC5682Z can be easily configured to drive a doubly terminated 50Ω cable using a properly selected RF
transformer. Figure 39 and Figure 40 show the 50Ω doubly terminated transformer configuration with 1:1 and 4:1
impedance ratio, respectively. The center tap of the primary input of the transformer must be connected to AVDD
to enable a dc current flow. Applying a 20-mA full-scale output current would lead to a 0.5 VPP for a 1:1
transformer and a 1 VPP output for a 4:1 transformer. The low dc-impedance between IOUT1 or IOUT2 and the
transformer center tap sets the center of the ac-signal at AVDD, so the 1 VPP output for the 4:1 transformer
results in an output between AVDD + 0.5 V and AVDD – 0.5 V.
AVDD
(3.3 V)
50 W
1:1
IOUT1
RLOAD
100 W
50 W
IOUT2
50 W
AVDD (3.3 V)
Figure 39. Driving a Doubly Terminated 50-Ω Cable Using a 1:1 Impedance Ratio Transformer
30
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AVDD (3.3 V)
100 W
4:1
IOUT1
RLOAD
50 W
IOUT2
100 W
AVDD (3.3 V)
Figure 40. Driving a Doubly Terminated 50-Ω Cable Using a 4:1 Impedance Ratio Transformer
8.3.13 Designing the PLL Loop Filter
To minimize phase noise given for a given fDAC and M/N, the values of PLL_gain and PLL_range are selected
so that GVCO is minimized and within the MIN and MAX frequency for a given setting.
The external loop filter components C1, C2, and R1 are set by the GVCO, M/N, the loop phase margin φd and the
loop bandwidth ωd. Except for applications where abrupt clock frequency changes require a fast PLL lock time, it
is suggested that φd be set to at least 80 degrees for stable locking and suppression of the phase noise side
lobes. Phase margins of 60 degrees or less can be sensitive to board layout and decoupling details.
See Figure 41, the recommend external loop filter topology. C1, C2, and R1 are calculated by the following
equations:
t2 ö
æ
C1 = t1ç 1 t3 ÷ø
è
C2 =
t1 ´ t2
t3
R1 =
t32
t1(t3 - t2 )
(12)
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where,
t1 =
K dK VCO
w2
d
(tan Φd + sec Φd )
t2 =
1
wd (tan Φd + sec Φd )
t3 =
tan Φd + sec Φd
wd
(13)
charge pump current: iqp = 1 mA
vco gain: KVCO = 2π × GVCO rad/V
PFD Frequency: ωd ≤160 MHz
phase detector gain: Kd = iqp ÷ (2 × π × M) A/rad
An Excel spreadsheet is available from Texas Instruments for automatically calculating the values for C1, R1 and
C2 in the DAC5682 LPF Caluclator (SLAC169).
DAC5682Z PLL
LPF
R1
(Pin 64)
PLL
C2
External
Loop
Filter
C1
Figure 41. Recommended External Loop Filter Topology
8.3.14 Test Methodology
Typical AC specifications were characterized with the DAC5682ZEVM using the test configuration shown in
Figure 42. A sinusoidal master clock frequency is generated by an HP8665B signal generator and into a splitter.
One output drives an Agilent 8133A pulse generator, and the other drives the CDCM7005 clock driver. The
8133A converts the sinusoidal frequency into a square wave output clock and drives an Agilent ParBERT
81250A pattern-generator clock. On the EVM, the DAC5682Z CLKIN/C input clock is driven by an CDCM7005
clock distribution chip that is configured to simply buffer the external 8665B clock or divide it down for PLL test
configurations.
The DAC5682Z output is characterized with a Rohde and Schwarz FSU spectrum analyzer. For WCDMA signal
characterization, it is important to use a spectrum analyzer with high IP3 and noise subtraction capability so that
the spectrum analyzer does not limit the ACPR measurement. For all specifications, both DACA and DACB are
measured and the lowest value used as the specification.
DAC5682ZEVM SMA Adapter Board
P
N
DCLK
P
N
100
CMIX1
I-FIR1
Opt.
Clock
Divider
Splitter
3.3 V
100
3.3 V
Rohde &
Schwartz
FSU
Spectrum
Analyzer
DAC-B
DLL
CDCM7005
Agilent 8133A
Pulse Generator
100
3.3 V
100
100
36 each
SMA-SMA cables
Optional
Divider
DAC-A
opt.
PLL
CLKIN
CLKINC
SYNC
Q-FIR1
Pattern
Memory
100
CMIX0
P
N
I-FIR0
D0
3.3 V
100
100
FIFO & Demux
N
3.3 V
DAC5682Z DAC
P
Stacking Interface Connector
D15
Q-FIR0
Agilent 81205A
ParBERT
3.3 V
Swap Cable
For DAC-B
measurements
Loop
Filter
100
DAC5682ZEVM
HP8665B
Synthesized
Signal
Generator
Figure 42. DAC5682Z Test Configuration for Normal Clock Mode
32
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8.4 Device Functional Modes
8.4.1 Dual-Channel Real Upconversion
The DAC5682Z can be used in a dual channel mode with real upconversion by mixing with a 1, –1, … sequence
in the signal chain to invert the spectrum. This mixing mode maintains isolation of the A and B channels. The two
points of mixing, CMIX0 and CMIX1, follow each FIR filter. The mixing modes for each CMIX block are controlled
by CMIX0_mode(1:0) and CMIX1(1:0) in register CONFIG2. The wide bandwidths of both FIR0 and FIR1 (40%
passband) provide options for setting the frequency ranges listed in Table 5. With the High Pass (2x2 HP mode),
High Pass/Low Pass (2X4 HP/LP mode) and Low Pass/High Pass (2X4 LP/HP mode) settings, the upconverted
signal is spectrally inverted.
Table 5. Dual-Channel Real Upconversion Options
MODE NAME
INTERP.
FACTOR
FIR0,
CMIX0
MODE
(1)
FIR1,
CMIX1
MODE
INPUT
FREQUENCY (1)
OUTPUT
FREQUENCY (1)
SIGNAL
BANDWIDTH (1)
SPECTRUM
INVERTED?
2X2
X2
--
LP
0.0 to 0.4 × fDATA
0.0 to 0.4 × fDATA
0.4 × fDATA
No
2X2 HP
X2
--
HP
0.0 to 0.4 × fDATA
0.6 to 1.0 × fDATA
0.4 × fDATA
Yes
1X4
X4
LP
LP
0.0 to 0.4 × fDATA
0.0 to 0.4 × fDATA
0.4 × fDATA
No
2X4
X4
LP
LP
0.0 to 0.4 × fDATA
0.0 to 0.4 × fDATA
0.4 × fDATA
No
2X4 HP/LP
X4
HP
LP
0.2 to 0.4 × fDATA
0.6 to 0.8 × fDATA
0.2 × fDATA
Yes
2X4 HP/HP
X4
HP
HP
0.2 to 0.4 × fDATA
1.2 to 1.4 × fDATA
0.2 × fDATA
No
2X4 LP/HP
X4
LP
HP
0.0 to 0.4 × fDATA
1.6 to 2.0 × fDATA
0.4 × fDATA
Yes
fDATA is the input data rate of each channel after de-interleaving.
8.4.2 Clock and Data Modes
There are two modes of operation to drive the internal clocks on the DAC5682Z. Timing diagrams for both
modes are shown in Figure 43. EXTERNAL CLOCK MODE accepts an external full-rate clock input on the
CLKIN/CLKINC pins to drive the DACs and final logic stages while distributing an internally divided down clock
for lower speed logic such as the interpolating FIRs. PLL CLOCK MODE uses an internal clock multiplying PLL
to derive the full-rate clock from an external lower rate reference frequency on the CLKIN/CLKINC pins. In both
modes, an LVDS half-rate data clock (DCLKP/DCLKN) is provided by the user and is typically generated by a
toggling data bit to maintain LVDS data to DCLK timing alignment. LVDS data relative to DCLK is input using
Double Data Rate (DDR) switching using both rising and falling edges as shown in the both figures below. The
CONFIG10 register contains user controlled settings for the DLL to adjust for the DCLK input frequency and
various tSKEW timing offsets between the LVDS data and DCLK. The CDCM7005 and CDCE62005 from Texas
Instruments are recommended for providing phase aligned clocks at different frequencies for device-to-device
clock distribution and multiple DAC synchronization.
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CLKINC
PLL = 4X
CLKIN
Two Clock Mode Shown: PLL = 4X and EXTERNAL (PLL = OFF)
CLKIN
EXTERNAL
CLKINC
DACCLK
(Internal)
DCLKN
DCLKP
tSKEW(A)
tSKEW(B)
Valid Data (A)
tS
tH
Valid Data (B)
SYNCN
Transmit Enable / Synchronization Event
SYNCP
D[15:0]N
D[15:0]P
Single DAC Mode (1X1)
A0
A1
A2
A3
AN
AN+1
Dual DAC Mode (2X2)
A0
B0
A1
B1
AN-2
BN-2
Figure 43. Clock and Data Timing Diagram
8.4.3 PLL Clock Mode
In PLL Clock Mode, the user provides an external reference clock to the CLKIN/C input pins. Refer to Figure 44.
An internal clock multiplying PLL uses the lower-rate reference clock to generate a high-rate clock for the DAC.
This function is very useful when a high-rate clock is not already available at the system level; however, the
internal VCO phase noise in PLL Clock Mode may degrade the quality of the DAC output signal when compared
to an external low jitter clock source.
The internal PLL has a type four phase-frequency detector (PFD) comparing the CLKIN/C reference clock with a
feedback clock to drive a charge pump controlling the VCO operating voltage and maintaining synchronization
between the two clocks. An external low-pass filter is required to control the loop response of the PLL. See
Designing the PLL Loop Filter for the filter setting calculations. This is the only mode where the LPF filter applies.
The input reference clock N-Divider is selected by CONFIG9 PLL_n(2:0) for values of ÷1, ÷2, ÷4 or ÷8. The VCO
feedback clock M-Divider is selected by CONFIG9 PLL_m(4:0) for values of ÷1, ÷2, ÷4, ÷8, ÷16 or ÷32. The
combination of M-Divider and N-Divider form the clock multiplying ratio of M/N. If the reference clock frequency is
greater than 160 MHz, use a N-Divider of ÷2, ÷4 or ÷8 to avoid exceeding the maximum PFD operating
frequency.
For DAC sample rates less than 500MHz, the phase noise of DAC clock signal can be improved by programming
the PLL for twice the desired DAC clock frequency, and setting the CONFIG11 VCO_div2 bit. If not using the
PLL, set CONFIG5 PLL_bypass and CONFIG6 PLL_sleep to reduce power consumption. In some cases, it
may be useful to reset the VCO control voltage by toggling CONFIG11 PLL_LPF_reset.
34
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External
Loop
Filter
(Pin 64)
LPF
(3.3V, Pin 9)
IOVDD
(1.8V, Pin 1)
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CLKVDD
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PLL Bypass
Clock Multiplying PLL
CLKIN
CLKINC
FREF
To internal
DAC clock
distribution
FREF/N
N–Divider
(1, 2, 4, 8)
PFD
FVCO/M
FVCO
VCO
Charge
Pump
FPLL
M-Divider
( 1,2,4,8,16,32)
FVCO
÷2
FVCO/2
PLL Sleep
PLL_sleep
(CONFIG 6)
PLL_n(2:0)
(CONFIG9)
PLL_m(4:0)
(CONFIG9)
PLL_LPF_reset
(CONFIG11)
VCO_div2
(CONFIG11)
PLL_bypass
via CONFIG5
PLL_gain(1:0),
PLL_range(3:0)
(CONFIG11)
Figure 44. Functional Block Diagram for PLL
8.4.4 Recommended Multi-DAC Synchronization Procedure
The DAC5682Z provides a mechanism to synchronize multiple DAC devices in a system. The procedure has two
steps involving control of the CONFIG5 clkdiv_sync_dis as well as external control of the LVDS SYNCP/N
input. (All DACs involved need to be configured to accept the external SYNCP/N input and not "software" sync
mode).
1. Synchronize Clock Dividers (for each DAC):
(a) Set CONFIG5 clkdiv_sync_dis = 0.
(b) Toggle SYNCP/N input to all DACs simultaneously (same input to all DACs).
2. Synchronize FIFO pointers (for each DAC):
(a) Set CONFIG5 clkdiv_sync_dis = 1 (Disable clock divider re-sync).
(b) Wait a minimum of 50 CLKIN cycles from previous SYNCP/N toggle. In practice, the time required to
write the above register value will typically occupy more than 50 cycles.
(c) Assert SYNCP/N input and hold at 1 to all DACs simultaneously. Holding this at 1 is effectively the
TXENABLE for the chip so data will be output on the analog pins.
3. After the normal pipeline delay of the device, the outputs of all DACs will be synchronized to within ±1 DAC
clock cycle.
8.4.5 Digital Self Test Mode
The DAC5682Z has a Digital Self Test (SLFTST) mode to designed to enable board level testing without
requiring specific input data test patterns. The SLFTST mode is enabled via the CONFIG1 SLFTST_ena bit and
results are only valid when CONFIG3 SLFTST_err_mask bit is cleared. An internal Linear Feedback Shift
Register (LFSR) is used to generate the input test patterns for the full test cycle while a checksum result is
computed on the digital signal chain outputs. The LVDS input data bus is ignored in SLFTST mode. After the test
cycle completes, if the checksum result does not match a hardwired comparison value, the STATUS4
SLFTST_err bit is set and will remain set until cleared by writing a ‘0’ to the SLFTST_err bit. A full self test cycle
requires no more than 400,000 CLKIN/C clock cycles to complete and will automatically repeat until the
SLFTEST_ena bit is cleared.
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To
1.
2.
3.
4.
5.
6.
7.
8.
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initiate a the Digital Self Test:
Provide a normal CLKIN/C input clock. (The PLL is not used in SLFTST mode)
Provide a RESETB pulse to perform a hardware reset on device.
Program the registers with the values shown in Table 6. These register values contain the settings to
properly configure the SLFTST including SLFTST_ena and SLFTST_err_mask bits
Provide a ‘1’ on the SYNCP/N input to initiate TXENABLE.
Wait at a minimum of 400,000 CLKIN/C cycles for the SLFTST to complete. Example: If CLKIN = 1GHz, then
the wait period is 400,000 × 1 / 1GHz = 400 μSec.
Read STATUS4 SLFTST_err bit. If set, a self test error has occurred. The SLFTST_err status may
optionally be programmed to output on the SDO pin if using the 3-bit SIF interface. See Table 6 Note (1).
(Optional) The SLFTST function automatically repeats until SLFTST_ena bit is cleared. To the loop the test,
write a ‘0’ to STATUS4 SLFTST_err to clear previous errors and continue at step 5 above.
To continue normal operating mode, provide another RESETB pulse and reprogram registers to the desired
normal settings.
Table 6. Digital Self Test (SLFTST) Register Values
(1)
REGISTER
ADDRESS (hex)
VALUE (Binary)
VALUE (Hex)
CONFIG1
01
00011000
18
CONFIG2
02
11101010
EA
CONFIG3
03
10110000
B0
STATUS4
04
00000000
00
CONFIG5
05
00000110
06
CONFIG6
06
00001111
0F
CONFIG12
0C
00001010
0A
CONFIG13
0D
01010101
55
CONFIG14 (1)
0E
00001010
0A
CONFIG15
0F
10101010
AA
All others
–
Default
Default
If using a 3-bit SIF interface, the SDO pin can be programmed to report SLFTST_err status via the SDO_fun_sel(2:0) bits. In this case,
set CONFIG14 = ‘10101010’ or AA hex.
8.5 Programming
8.5.1 Serial Interface
The serial port of the DAC5682Z is a flexible serial interface which communicates with industry standard
microprocessors and microcontrollers. The interface provides read/write access to all registers used to define the
operating modes of DAC5682Z. It is compatible with most synchronous transfer formats and can be configured
as a 3 or 4 pin interface by SIF4 in register CONFIG5. In both configurations, SCLK is the serial interface input
clock and SDENB is serial interface enable. For 3 pin configuration, SDIO is a bidirectional pin for both data in
and data out. For 4 pin configuration, SDIO is data in only and SDO is data out only. Data is input into the device
with the rising edge of SCLK. Data is output from the device on the falling edge of SCLK.
Each read/write operation is framed by signal SDENB (Serial Data Enable Bar) asserted low for 2 to 5 bytes,
depending on the data length to be transferred (1–4 bytes). The first frame byte is the instruction cycle which
identifies the following data transfer cycle as read or write, how many bytes to transfer, and what address to
transfer the data. indicates the function of each bit in the instruction cycle and is followed by a detailed
description of each bit. Frame bytes 2 to 5 comprise the data transfer cycle.
Bit
Description
36
MSB
7
R/W
6
N1
5
N0
4
A4
3
A3
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2
A2
1
A1
LSB
0
A0
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R/W
Identifies the following data transfer cycle as a read or write operation. A high indicates a read
operation from DAC5682Z and a low indicates a write operation to DAC5682Z.
[N1 : N0]
Identifies the number of data bytes to be transferred per Table 5 below. Data is transferred MSB
first.
Table 7. Number of Transferred Bytes Within One
Communication Frame
[A4 : A0]
N1
N0
Description
0
0
Transfer 1 Byte
0
1
Transfer 2 Bytes
1
0
Transfer 3 Bytes
1
1
Transfer 4 Bytes
Identifies the address of the register to be accessed during the read or write operation. For multibyte transfers, this address is the starting address. Note that the address is written to the
DAC5682Z MSB first and counts down for each byte.
Figure 45 shows the serial interface timing diagram for a DAC5682Z write operation. SCLK is the serial interface
clock input to DAC5682Z. Serial data enable SDENB is an active low input to DAC5682Z. SDIO is serial data in.
Input data to DAC5682Z is clocked on the rising edges of SCLK.
Instruction Cycle
Data Transfer Cycle (s)
SDENB
SCLK
SDIO
r/w
N1
N0
A4
A3
A2
A1
A0
D7
tS (SDENB)
D6
D5
D4
D3
D2
D1
D0
tSCLK
SDENB
SCLK
SDIO
th (SDIO)
tS (SDIO)
tSCLKL
tSCLKH
Figure 45. Serial Interface Write Timing Diagram
Figure 46 shows the serial interface timing diagram for a DAC5682Z read operation. SCLK is the serial interface
clock input to DAC5682Z. Serial data enable SDENB is an active low input to DAC5682Z. SDIO is serial data in
during the instruction cycle. In 3 pin configuration, SDIO is data out from DAC5682Z during the data transfer
cycle(s), while SDO is in a high-impedance state. In 4 pin configuration, SDO is data out from DAC5682Z during
the data transfer cycle(s). At the end of the data transfer, SDO will output low on the final falling edge of SCLK
until the rising edge of SDENB when it will 3-state.
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Instruction Cycle
Data Transfer Cycle(s)
SDENB
SCLK
SDIO
r/w
N1
N0
-
A3
A2
A1
SDO
A0
D7
D6
D5
D4
D3
D2
D1
D0
0
D7
D6
D5
D4
D3
D2
D1
D0
0
3 pin Configuration Output
4 pin Configuration Output
SDENB
SCLK
SDIO
SDO
Data n
Data n-1
td (Data)
Figure 46. Serial Interface Read Timing Diagram
38
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8.6 Register Maps
The primary modes of operation, listed in Table 8, are selected by registers CONFIG1, CONFIG2, and
CONFIG3.
Table 8. DAC5682Z Modes of Operation
Device
Config.
LVDS
Input
Data
Mode
Max CLKIN
Freq (MHz) (1)
Max DCLK
Freq [DDR]
(MHz)
Max Total
Input Bus
Rate
(MSPS)
Max Input Data
Rate Per Chan
(#Ch @ MSPS)
Max Signal
BW Per DAC
(MHz) (2)
–
Single Real
A
1000
500
1000
1 at 1000
500
–
LP
–
HP
Single Real
A
1000
250
500
1 at 500
200
Single Real
A
1000
250
500
1 at 500
X4
LP
200
LP
Single Real
A
1000
125
250
1 at 250
1
X4
100
LP
HP
Single Real
A
1000
125
250
1 at 250
1X4 HP/LP
1
100
X4
HP
LP
Single Real
A
1000
125
250
1 at 250
1X4 HP/HP
50
1
X4
HP
HP
Single Real
A
1000
125
250
1 at 250
50
2X1
2
X1
–
–
Dual Real
A/B
500
500
1000
2 at 500
250
2X2
2
X2
–
LP
Dual Real
A/B
1000
500
1000
2 at 500
200
2X2 HP
2
X2
–
HP
Dual Real
A/B
1000
500
1000
2 at 500
200
2X2 CMIX
2
X2
–
LP,
Fs/4
Complex
A/B
1000
500
1000
2 at 500
200
2X4
2
X4
LP
LP
Dual Real
A/B
1000
250
500
2 at 250
100
2X4 LP/HP
2
X4
LP
HP
Dual Real
A/B
1000
250
500
2 at 250
100
2X4 CMIX
2
X4
LP
LP,
Fs/4
Complex
A/B
1000
250
500
2 at 250
100
2X4 HP/LP
2
X4
HP
LP
Dual Real
A/B
1000
250
500
2 at 250
50
2X4 HP/HP
2
X4
HP
HP
Dual Real
A/B
1000
250
500
2 at 250
50
No. of
DACs
Out
Interp.
Factor
FIR0,
CMIX0
Mode
FIR1,
CMIX1
Mode
1X1
(Bypass)
1
X1
–
1X2
1
X2
1X2 HP
1
X2
1X4
1
1X4 LP/HP
Mode
Name
(1)
(2)
Also the final DAC sample rate in MSPS.
Assumes a 40% passband for FIR0 and/or FIR1 filters in all modes except 1X1 and 2X1 where simple Nyquist frequency is listed.
Slightly wider bandwidths may be achievable depending on filtering requirements. Refer to FIR Filters section for more detail on filter
characteristics. Also refer to Table 5 for IF placement and upconversion considerations.
Table 9. Register Map
Name
Address
Default
(MSB)
Bit 7
Bit 6
Bit 5
STATUS0
0x00
0x03
PLL_lock
DLL_lock
Unused
CONFIG1
0x01
0x10
CONFIG2
0x02
0xC0
Twos_ comp
dual_DAC
FIR2x4x
Unused
CONFIG3
0x03
0x70
DAC_offset _ena
SLFTST_err
_mask
FIFO_err_ mask
Pattern_err
_mask
SwapAB_ out
B_equals _A
SW_sync
SW_sync _sel
STATUS4
0x04
0x00
Unused
SLFTST_err
FIFO_err
Pattern_ err
Unused
Unused
Unused
Unused
Reserved
DLL_ sleep
DAC_delay(1:0)
Unused
Bit 4
Bit 3
fir_ena
SLFTST _ena
Bit 2
(LSB)
Bit 0
Bit 1
device_ID(2:0)
version(1:0)
FIFO_offset(2:0)
CMIX1_mode(1:0)
CMIX0_mode(1:0)
CONFIG5
0x05
0x00
SIF4
rev_bus
clkdiv_ sync_dis
Reserved
Reserved
DLL_ bypass
PLL_
bypass
CONFIG6
0x06
0x0C
Reserved
Unused
Sleep_B
Sleep_A
BiasLPF_A
BiasLPF_B
PLL_ sleep
CONFIG7
0x07
0xFF
CONFIG8
0x08
0x00
Reserved
CONFIG9
0x09
0x00
PLL_m(4:0)
CONFIG10
0x0A
0x00
CONFIG11
0x0B
0x00
CONFIG12
0x0C
0x00
CONFIG13
0x0D
0x00
CONFIG14
0x0E
0x00
CONFIG15
0x0F
0x00
DACA_gain(3:0)
DACB_gain(3:0)
DLL_ restart
DLL_delay(3:0)
PLL_LPF _reset
VCO_div2
Reserved(1:0)
Reserved
PLL_n(2:0)
DLL_invclk
PLL_gain(1:0)
DLL_ifixed(2:0)
PLL_range(3:0)
Offset_sync
OffsetA(12:8)
OffsetA(7:0)
SDO_func_sel(2:0)
OffsetB(12:8)
OffsetB(7:0)
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8.6.1 Register Name: STATUS0 – Address: 0x00, Default = 0x03
7
PLL_lock
0
6
DLL_lock
0
5
Unused
0
4
0
3
device_ID(2:0)
0
2
1
0
version(1:0)
0
1
1
PLL_lock:
Asserted when the internal PLL is locked. (Read Only)
DLL_lock:
Asserted when the internal DLL is locked. Once the DLL is locked, this bit should remain a
‘1’ unless the DCLK input clock is removed or abruptly changes frequency causing the DLL
to fall out of lock. (Read Only)
device_ID(2:0):
Returns ‘000’ for DAC5682Z Device_ID code. (ReadOnly)
version(1:0):
A hardwired register that contains the register set version of the chip. (ReadOnly)
version (1:0)
Identification
‘01’
‘10’
‘11'
PG1.0 Initial Register Set
PG1.1 Register Set
Production Register Set
8.6.2 Register Name: CONFIG1 – Address: 0x01, Default = 0x10
7
6
DAC_delay(1:0)
0
0
5
Unused
0
4
FIR_ena
1
3
SLFTST_ena
0
2
0
1
FIFO_offset(2:0)
0
0
0
DAC_delay(1:0):
DAC data delay adjustment. (0–3 periods of the DAC clock) This can be used to adjust
system level output timing. The same delay is applied to both DACA and DACB data paths.
FIR_ena:
When set, the interpolation filters are enabled.
SLFTST_ena:
When set, a Digital Self Test (SLFTST) of the core logic is enabled. Refer to Digital Self
Test Mode for details on SLFTST operation.
FIFO_offset(2:0):
Programs the output pointer location of the FIFO, allowing the input pointer to be shifted –4
to +3 positions upon SYNC. Default offset is 0 and is updated upon each sync event.
40
FIFO_offset(2:0)
Offset
011
+3
010
+2
001
+1
000
0
111
–1
110
–2
101
–3
100
–4
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8.6.3 Register Name: CONFIG2 – Address: 0x02, Default = 0xC0
7
Twos_comp
1
6
dual_DAC
1
5
FIR2x4x
0
4
Unused
0
3
2
CMIX1_mode(1:0)
0
0
1
0
CMIX0_mode(1:0)
0
0
Twos_comp:
When set (default) the input data format is expected to be 2’s complement, otherwise
offset binary format is expected.
dual_DAC:
Selects between dual DAC mode (default) and single DAC mode. This bit is also used
to select input interleaved data.
FIR2x4x:
When set, 4X interpolation of the input data is performed, otherwise 2X interpolation.
CMIX1_mode(1:0):
Determines the mode of FIR1 and final CMIX1 blocks. Settings apply to both A and B
channels. Refer to Table 3 for a detailed description of CMIX1 modes.
CMIX1_mode(1)
CMIX1_mode(0)
Normal (Low Pass)
Mode
0
0
High Pass
0
1
+FDAC /4
1
0
–FDAC/4
1
1
CMIX0_mode(1:0): Determines the mode of FIR0 and CMIX0 blocks. Because CMIX0 is located between
FIR0 and FIR1, its output is half-rate. Refer to Table 2 for a detailed description of CMIX0
modes. The table below shows the effective Fs/4 or ±Fs/8 mixing with respect to the final
DAC sample rate. Settings apply to both A and B channels.
CMIX1_mode(1)
CMIX1_mode(0)
Normal (Low Pass)
Mode
0
0
High Pass
0
1
+FDAC /8
1
0
–FDAC/8
1
1
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8.6.4 Register Name: CONFIG3 – Address: 0x03, Default = 0x70
7
DAC_offset
_ena
0
6
SLFTST_err
_mask
5
FIFO_err_
mask
4
Pattern_err_
mask
3
SwapAB_out
2
B_equals_A
1
SW_sync
0
SW_sync_sel
1
1
1
0
0
0
0
DAC_offset_ena:
When set, the values of OffsetA(12:0) and OffsetB(12:0) in CONFIG12 through
CONFIG15 registers are summed into the DAC-A and DAC-B data paths. This provides
a system-level offset adjustment capability that is independent of the input data.
SLFTST_err_mask:
When set, masks out the SLFTST_err bit in STATUS4 register. Refer to Digital Self
Test Mode for details on SLFTST operation.
FIFO_err_mask:
When set, masks out the FIFO_err bit in STATUS4 register.
Pattern_err_mask:
When set, masks out the Pattern err bit in STATUS4 register.
SwapAB_out:
When set, the A/B data paths are swapped prior to routing to the DAC-A and DAC-B
outputs.
B_equals_A:
When set, the data routed to DAC-A is also routed to DAC-B. This allows wire OR’ing of
the two DAC outputs together at the board level to create a 2X drive strength single
DAC output.
SW_sync:
This bit can be used as a substitute for the LVDS external SYNC input pins for both
synchronization and transmit enable control.
SW_sync_sel:
When set, the SW_sync bit is used as the only synchronization input and the LVDS
external SYNC input pins are ignored.
8.6.5 Register Name: STATUS4 – Address: 0x04, Default = 0x00
7
Unused
0
6
SLFTST_err
0
5
FIFO_err
0
4
Pattern_err
0
3
Unused
0
2
Unused
0
1
Unused
0
0
Unused
0
SLFTST_err:
Asserted when the Digital Self Test (SLFTST) fails. To clear the error, write a ‘0’ to this
register bit. This bit is also output on the SDO pin when the Self Test is enabled via
SLFTST_ena control bit in CONFIG1. Refer to Digital Self Test Mode for details on
SLFTST operation.
FIFO_err:
Asserted when the FIFO pointers over run each other causing a sample to be missed. To
clear the error, write a ‘0’ to this register bit.
Pattern_err:
A digital checkerboard pattern compare function is provided for board level confidence
testing and DLL limit checks. If the Pattern_err_mask bit via CONFIG3 is cleared, logic is
enabled to continuously monitor input FIFO data. Any received data pattern other than
0xAAAA or 0x5555 causes this bit to be set. To clear the error, flush out the previous
pattern error by inputting at least 8 samples of the 0xAAAA and/or 0x5555, then write a ‘0’
to this register bit.
42
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8.6.6 Register Name: CONFIG5 – Address: 0x05, Default = 0x00
7
SIF4
6
rev_bus
0
0
5
clkdiv_sync
_dis
0
4
Reserved
3
Reserved
2
DLL_bypass
1
PLL_bypass
0
Reserved
0
0
0
0
0
SIF4:
When set, the serial interface is in 4 pin mode, otherwise it is in 3 pin mode. Refer to
SDO_func_sel (2:0) bits in CONFIG14 register for options available to output status
indicator data on the SDO pin.
rev_bus:
Reverses the LVDS input data bus so that the MSB to LSB order is swapped. This
function is provided to ease board level layout and avoid wire crossovers in case the
LVDS data source output bus is mirrored with respect to the input data bus of the DAC.
clkdiv_sync_dis:
Disables the clock divider sync when this bit is set.
Reserved (Bit 4):
Set to 0 for proper operation.
Reserved (Bit 3):
Set to 0 for proper operation.
DLL_bypass:
When set, the DLL is bypassed and the LVDS data source is responsible for providing
correct setup and hold timing.
PLL_bypass:
When set, the PLL is bypassed.
Reserved (Bit 0):
Set to 0 for proper operation.
8.6.7 Register Name: CONFIG6 – Address: 0x06, Default = 0x0C
7
Reserved
0
6
Unused
0
5
Sleep_B
0
4
Sleep_A
0
3
BiasLPF_A
1
2
BiasLPF_B
1
1
PLL_sleep
0
0
DLL_sleep
0
Reserved (Bit 7):
Set to 0 for proper operation.
Sleep_B:
When set, DACB is put into sleep mode. DACB is not automatically set into sleep mode
when configured for single DAC mode through dual_DAC bit in CONFIG2. Set this
Sleep_B bit for the lowest power configuration in single DAC mode because output is on
DACA only.
Sleep_A:
When set, DACA is put into sleep mode.
BiasLPF_A:
Enables a 95 kHz low pass filter corner on the DACA current source bias when cleared. If
this bit is set, a 472 kHz filter corner is used.
BiasLPF_B:
Enables a 95 kHz low pass filter corner on the DACB current source bias when cleared. If
this bit is set, a 472 kHz filter corner is used.
PLL_sleep:
When set, the PLL is put into sleep mode.
DLL_sleep:
When set, the DLL is put into sleep mode.
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8.6.8 Register Name: CONFIG7 – Address: 0x07, Default = 0xFF
7
6
5
4
3
2
1
0
1
1
1
2
DLL_restart
0
1
DACA_gain(3:0)
1
1
DACB_gain(3:0)
1
1
1
DACA_gain(3:0):
Scales DACA output current in 16 equal steps.
VEXTIO
x (DACA_gain + 1)
Rbias
DACB_gain(3:0):
Same as above except for DACB.
8.6.9 Register Name: CONFIG8 – Address: 0x08, Default = 0x00
7
0
6
0
5
Reserved
0
4
0
3
0
0
Reserved
0
0
Reserved (7:3):
Set to ‘00000’ for proper operation.
DLL_restart:
This bit is used to restart the DLL. When this bit is set, the internal DLL loop filter is reset to
zero volts, and the DLL delay line is held at the center of its bias range. When cleared, the
DLL will acquire lock to the DCLK signal. A DLL restart is accomplished by setting this bit
with a serial interface write, and then clearing this bit with another serial interface write. Any
interruption in the DCLK signal or changes to the DLL programming in the CONFIG10
register must be followed by this DLL restart sequence. Also, when this bit is set, the
DLL_lock indicator in the STATUS0 register is cleared.
Reserved (1:0):
Set to ‘00’ for proper operation
44
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8.6.10 Register Name: CONFIG9 – Address: 0x09, Default = 0x00
7
6
0
0
5
PLL_m(4:0)
0
4
3
2
0
0
0
1
PLL_n(2:0)
0
0
0
PLL_m: M portion of the M/N divider of the PLL thermometer encoded:
PLL_m(4:0)
M value
00000
1
00001
2
00011
4
00111
8
01111
16
11111
32
All other values
Invalid
PLL_n: N portion of the M/N divider of the PLL thermometer encoded. If supplying a high rate CLKIN
frequency, the PLL_n value should be used to divide down the input CLKIN to maintain a maximum
PFD operating of 160 MHz.
PLL_n(2:0)
N value
000
1
001
2
011
4
111
8
All other values
Invalid
PLL Function:
é (M)ù
fvco = ê
ú x fref
ëê (N) ûú
where ƒref is the frequency of the external DAC clock input on the CLKIN/CLKINC pins.
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8.6.11 Register Name: CONFIG10 – Address: 0x0A, Default = 0x00
7
6
5
4
0
0
DLL_delay(3:0)
0
DLL_delay(3:0):
0
3
DLL_invclk
0
2
0
1
DLL_ifixed(2:0)
0
0
0
The DCLKP/N LVDS input data clock has a DLL to automatically skew the clock to LVDS
data timing relationship, providing proper setup and hold times. DLL_delay(3:0) is used to
manually adjust the DLL delay ± from the fixed delay set by DLL_ifixed(2:0). Adjustment
amounts are approximate.
DLL_delay(3:0)
Delay Adjust (degrees)
1000
50°
1001
55°
1010
60°
1011
65°
1100
70°
1101
75°
1110
80°
1111
85°
0000
90° (Default)
0001
95°
0010
100°
0011
105°
0100
110°
0101
115°
0110
120°
0111
125°
DLL_invclk:
When set, used to invert an internal DLL clock to force convergence to a different solution.
This can be used in the case where the DLL delay adjustment has exceeded the limits of
its range.
DLL_ifixed(2:0):
Adjusts the DLL delay line bias current. Refer to the Electrical Characteristics table. Used
in conjunction with the DLL_invclk bit to select appropriate delay range for a given DCLK
frequency:
'011' – maximum bias current and minimum delay range
'000' – mid scale bias current
'101' – minimum bias current and maximum delay range
'100' – do not use.
46
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8.6.12 Register Name: CONFIG11 – Address: 0x0B, Default = 0x00
7
PLL_LPF_
reset
0
6
VCO_div2
5
0
0
4
3
2
PLL_gain(1:0)
1
0
0
0
PLL_range(3:0)
0
0
0
PLL_LPF_reset:
When a logic high, the PLL loop filter (LPF) is pulled down to 0V. Toggle from ‘1’ to ‘0’ to
restart the PLL if an over-speed lock-up occurs. Over-speed can happen when the process
is fast, the supplies are higher than nominal, etc., resulting in the feedback dividers missing
a clock.
VCO_div2:
When set, the PLL CLOCK output is 1/2 the PLL VCO frequency. Used to run the VCO at
2X the needed clock frequency to reduce phase noise for lower input clock rates.
PLL_gain(1:0):
Used to adjust the PLL Voltage Controlled Oscillator (VCO) gain, KVCO. Refer to the
Electrical Characteristics table. By increasing the PLL_gain, the VCO can cover a broader
range of frequencies; however, the higher gain also increases the phase noise of the PLL.
In general, lower PLL_gain settings result in lower phase noise. The KVCO of the VCO can
also affect the PLL stability and is used to determine the loop filter components. See
section on determining the PLL filter components for more detail.
PLL_range(3:0):
Programs the PLL VCO fixed bias current. Refer to the Electrical Characteristics table. This
setting, in conjunction with the PLL_gain(1:0), sets the achievable frequency range of the
PLL VCO:
'000' – minimum bias current and lowest VCO frequency range
'111' – maximum bias current and highest VCO frequency range
8.6.13 Register Name: CONFIG12 – Address: 0x0C, Default = 0x00
7
6
Reserved(1:0)
0
0
5
Offset_sync
0
4
3
0
0
2
OffsetA(12:8)
0
1
0
0
0
Reserved(1:0):
Set to ‘00’ for proper operation.
Offset_sync:
On a change from ‘0’ to ‘1’ the values of the OffsetA(12:0) and OffsetB(12:0) control
registers are transferred to the registers used in the DAC-A and DAC-B offset calculations.
This double buffering allows complete control by the user as to when the change in the
offset value occurs. This bit does not auto-clear. Prior to updating new offset values, it is
recommended that the user clear this bit.
OffsetA(12:8):
Upper 5 bits of the offset adjustment value for the A data path. (SYNCED via Offset_sync)
8.6.14 Register Name: CONFIG13 – Address: 0x0D, Default = 0x00
7
6
5
4
3
2
1
0
0
0
0
0
OffsetA(7:0)
0
OffsetA(7:0):
0
0
0
Lower 8 bits of the offset adjustment value for the A data path. (SYNCED via Offset_sync)
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8.6.15 Register Name: CONFIG14 – Address: 0x0E, Default = 0x00
7
0
6
SDO_func_sel(2:0)
0
SDO_func_sel(2:0):
OffsetB(12:8):
5
4
3
0
0
0
2
OffsetB(12:8)
0
1
0
0
0
Selects the signal for output on the SDO pin. When using the 3 pin serial interface
mode, this allows the user to multiplex several status indicators onto the SDO pin. In 4
pin serial interface mode, programming this register to view one of the 5 available status
indicators will override normal SDO serial interface operation.
SDO_func_sel
(2:0)
Output to SDO
000, 110, 111
Normal SDO function
001
PLL_lock
010
DLL_lock
011
Pattern_err
100
FIFO_err
101
SLFTST_err
Upper 5 bits of the offset adjustment value for the B data path. (SYNCED via Offset_sync)
8.6.16 Register Name: CONFIG15 – Address: 0x0F, Default = 0x00
7
6
5
4
3
2
1
0
0
0
0
0
OffsetB(7:0)
0
OffsetB(7:0):
48
0
0
0
Lower 8 bits of the offset adjustment value for the B data path. (SYNCED via Offset_sync)
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9 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.
9.1 Application Information
The DAC5682z is a high-speed, wide bandwidth Digital-to-Analog converter. The dual DAC outputs can sample
at 1Gsps allowing synthesis of complex IQ signals from -400 to 400 MHz with a complex bandwidth of up to 400
MHz. When the DAC is operated in single channel bypass mode, the maximum data rate is 1Gsps and can
sustain a signal bandwidth of 500 MHz. The interpolation modes of the DAC allow the input baseband rates to be
2-4 times slower than the DAC output rate reducing the processing requirements of the digital baseband
processor and simplifies the DAC image filtering requirements. The coarse mixing blocks within the DAC allow
power efficient placement of the final carrier at the DAC output. Typically this dual DAC with its digital features is
very well equipped for complex quadrature communications applications, however it is also suitable for use in
applications that require arbitrary waveform generation.
9.2 Typical Application
A typical application for the DAC5682z is a wideband transmitter. The DAC is provided with some input digital
baseband signal and it outputs an analog carrier. A typical configuration is described below.
• Dual DAC mode
• Datarate = 491.52 Msps (DCLK LVPECL or LVDS)
• 2x Interpolation
• External clock mode = 983.04 MHz (CLKIN LVPECL or LVDS)
• Input data = 4C WCDMA with IF frequency at 184.32 MHz
• AVDD/IOVDD = 3.3 V
• DVDD/CLKVDD=1.8 V
• SYNCP/N = LVDS "1"
• IOUTAP/N and IOUTBP/N to transformers
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Typical Application (continued)
(1)
Power supply decoupling capacitors not shown.
(2)
Internal Reference configuration shown.
Figure 47. Typical Application Schematic
9.2.1 Design Requirements
The requirements for this design were to generate a 4-carrier WCDMA signal at an intermediate frequency of
184.32 MHz. The ACPR needs to be better than 65 dBc.
9.2.2 Detailed Design Procedure
The 4-carrier signal with an intermediate frequency of 184.32 MHz must be created in the digital processor at a
sample rate of 491.52 Msps for channels A and B. These 16 bit samples must be interleaved into ABAB... format
and placed on the 16b LVDS input port of the DAC.
A differential DAC clock must be generated from a clock source at 983.04 MHz and a data clock at 491.52 MHz.
This must be provided to the CLKIN and DCLK pins of the DAC respectively.
The DAC register map must be reset, then programmed for 2x interpolation and external clock mode as per the
data sheet. The digital sample format (2s complement or offset binary) must match the incoming data from the
processor. The SYNC signal must he held high for the DAC to have an analog output.
The IOUOTA and IOUTB differential connections must be connected to a transformer to provide a single ended
output. A typical 2:1 impedance transformer is used on the device EVM. The DAC5682zEVM provides a good
reference for this design example.
9.2.3 Application Curves
This spectrum analyzer plot shows the ACPR for the transformer output using x2 interpolation, PLL Off mode.
The results meet the system requirements for a minimum of 65 dBc ACPR.
50
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Typical Application (continued)
-20 Carrier Power: -15.85 dBm,
ACLR (5 MHz): 69.66 dB,
-30 ACLR (10 MHz): 70.65 dB,
Fdata = 491.52 MSPS,
IF = 184.32 MHz,
-40 x2 Interpolation
PLL Off
Power - dBm
-50
-60
-70
-80
-90
-100
-110
-120
160 165 170 175 180 185 190 195 200 205 210
f - Frequency - MHz
Figure 48. Four Carrier W-CDMA Test Model 1
9.3 System Examples
9.3.1 Digital Interface and Clocking Considerations for Application Examples
The DAC5682Z’s LVDS digital input bus can be driven by an FPGA or digital ASIC. This input signal can be
generated directly by the FPGA, or fed by a Texas Instruments Digital Up Converter (DUC) such as the GC5016
or GC5316. Optionally, a GC1115 Crest Factor Reduction (CFR) or Digital Pre-Distortion (DPD) processor may
be inserted in the digital signal chain for improving the efficiency of high-power RF amplifiers. For the details on
the high-rate digital interface of the DAC, refer to LVDS Data Interfacing.
A low phase noise clock for the DAC at the final sample rate can be generated by a VCXO and a Clock
Synchronizer/PLL such as the Texas Instruments CDCM7005 or CDCE62005, which can also provide other
system clocks. An optional system clocking solution can use the DAC in clock multiplying PLL mode in order to
avoid distributing a high-frequency clock at the DAC sample rate; however, the internal VCO phase noise of the
DAC in PLL mode may degrade the quality of the DAC output signal.
9.3.2 Single Complex Input, Real IF Output Radio
Refer to Figure 49 for an example Single Complex Input, Real IF Output Radio. The DAC5682Z receives an
interleaved complex I/Q baseband input data stream and increases the sample rate through interpolation by a
factor of 2 or 4. By performing digital interpolation on the input data, undesired images of the original signal can
be push out of the band of interest and more easily suppressed with analog filters. Complex mixing is available at
each stage of interpolation using the CMIX0 and CMIX1 blocks to up-convert the signal to a frequency placement
at a multiples ±Fdac/8 or ±Fdac/4. Only the real portion of the digital signal is converted by DAC-A while DAC-B
can be programmed to sleep mode for reduced power consumption. The DAC output signal would typically be
terminated with a transformer (see Analog Current Outputs). An IF filter, either LC or SAW, is used to suppress
the DAC Nyquist zone images and other spurious signals before being mixed to RF with a mixer. The TRF3671
Frequency Synthesizer, with integrated VCO, may be used to drive the LO input of the mixer for frequencies
between 375 and 2380 MHz.
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System Examples (continued)
Interleaved
I/Q Data
SYNCP/N
I-FIR1
100
RF
Processing
100
CMIX1
I-FIR0
100
CMIX0
100
3.3V
DAC-A
Q-FIR1
3.3V
DAC-B
Sleep
DCLKP/N
DLL
opt.
PLL
PLL/
DLL
1000 MHz
100
250 MHz
100
100
CLKIN/C
Q
D0P/N
100
Q-FIR0
I
3.3V
DAC5682Z DAC
FIFO & Demux
D15P/N
LVDS Data Interface
GC5016 or GC5316 DUC,
With GC1115 CFR and/or
DPD Processor
FPGA
375 MHz Min to 2380 MHz Max
(Depends on divider and
“dash #” of TRF3761)
Loop
Filter
Div
1/2/4
VCXO
÷4
÷1
VCO
NDivider
Clock Divider /
Distribution
VCTRL_IN
Loop
Filter
Loop
Filter
PLL
PFD
RDiv
CDCM7005
10 MHz
OSC
Note : For clarity, only signal paths are shown.
CPOUT
TRF3761-X PLL/VCO
Figure 49. System Diagram of a Complex Input, Real IF Output Radio
9.3.3 Dual Channel Real IF Output Radio
Refer to Figure 50 for an example Dual-Channel Real IF Output Radio. The DAC5682Z receives an interleaved
A/B input data stream and increases the sample rate through interpolation by a factor of 2 or 4. By performing
digital interpolation on the input data, undesired images of the original signal can be push out of the band of
interest and more easily suppressed with analog filters. Real mixing is available at each stage of interpolation
using the CMIX0 and CMIX1 blocks to up-convert the signal (see Dual-Channel Real Upconversion). Both DAC
output signals would typically be terminated with a transformer (see Analog Current Outputs). An IF filter, either
LC or SAW, is used to suppress the DAC Nyquist zone images and other spurious signals before being mixed to
RF with a mixer. The TRF3671 Frequency Synthesizer, with integrated VCO, may be used to drive a common
LO input of the mixers for frequencies between 375 and 2380 MHz. Alternatively, two separate TRF3761
synthesizers could be used for independent final RF frequency placement.
HP/LP
100
100
3.3V
3.3V
RF
Processing
3.3V
250 MHz
100
opt.
PLL
1000 MHz
100
3.3V
100
DLL
CLKIN/C
PLL/
DLL
RF
Processing
DAC-B
DCLKP/N
100
3.3V
DAC-A
HP/LP
HP/LP
A-FIR0
A-FIR1
B-FIR1
100
HP/LP
SYNCP/N
100
B-FIR0
Q
D0P/N
100
FIFO & Demux
I
LVDS Data Interface
GC5016 or GC5316 DUC,
With GC1115 CFR and/or
DPD Processor
D15P/N
3.3V
DAC5682Z DAC
100
Interleaved
A/B Data
FPGA
375 MHz Min to 2380 MHz Max
(Depends on divider and
“dash #” of TRF3761)
Loop
Filter
Div
1/2/4
VCXO
÷4
÷1
Clock Divider /
Distribution
VCO
NDivider
PLL
PFD
RDiv
CDCM7005
Note : For clarity, only signal paths are shown.
VCTRL_IN
Loop
Filter
Loop
Filter
10 MHz
OSC
CPOUT
TRF3761-X PLL/VCO
Figure 50. System Diagram of a Dual-Channel Real IF Output Radio
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System Examples (continued)
9.3.4 Direct Conversion Radio
Refer to Figure 51 for an example Direct Conversion Radio. The DAC5682Z receives an interleaved complex I/Q
baseband input data stream and increases the sample rate through interpolation by a factor of 2 or 4. By
performing digital interpolation on the input data, undesired images of the original signal can be push out of the
band of interest and more easily suppressed with analog filters.
For a Zero IF (ZIF) frequency plan, complex mixing of the baseband signal is not required. Alternatively, for a
Complex IF frequency plan the input data can be placed at an pre-placed at an IF within the bandwidth
limitations of the interpolation filters. In addition, complex mixing is available at each stage of interpolation using
the CMIX0 and CMIX1 blocks to up-convert the signal to a frequency placement at a multiples ±Fdac/8 or
±Fdac/4. The output of both DAC channels is used to produce a Hilbert transform pair and can be expressed as:
A(t) = I(t)cos(ωct) – Q(t)sin(ωct) m(t)
A(t) = I(t)cos(ωct) – Q(t)sin(ωct) mh(t)
(14)
(15)
where m(t) and mh(t) connote a Hilbert transform pair and ωc is the sum of the CMIX0 and CMIX1 frequencies.
The complex output is input to an analog quadrature modulator (AQM) such as the Texas Instruments TRF370333 for a single side-band (SSB) up conversion to RF. A passive (resistor only) interface to the AQM is
recommended, with an optional LC filter network. The TRF3671 Frequency Synthesizer with integrated VCO may
be used to drive the LO input of the TRF3703-33 for frequencies between 375 and 2380 MHz. Upper singlesideband upconversion is achieved at the output of the analog quadrature modulator, whose output is expressed
as:
RF(t) = I(t)cos(ωc + ωLO)t – Q(t)sin(ωc + ωLO)t
(16)
Flexibility is provided to the user by allowing for the selection of negative CMIX mixing sequences to produce a
lower-sideband upconversion. Note that the process of complex mixing translates the signal frequency from 0 Hz
means that the analog quadrature modulator IQ imbalance produces a sideband that falls outside the signal of
interest. DC offset error in DAC and AQM signal path may produce LO feed-through at the RF output which may
fall in the band of interest. To suppress the LO feed-through, the DAC5682Z provides a digital offset correction
capability for both DAC-A and DAC-B paths. (See DAC_offset_ena bit in CONFIG3.)
The complex IF architecture has several advantages over the real IF architecture:
• Uncalibrated side-band suppression ~ 35 dBc compared to 0 dBc for real IF architecture.
• Direct DAC to AQM interface – no amplifiers required
• Nonharmonic clock-related spurious signals fall out-of-band
• DAC 2nd Nyquist zone image is offset fDAC compared with fDAC– 2 × IF for a real IF architecture, reducing the
need for filtering at the DAC output.
• Uncalibrated LO feed through for AQM is ~ 35 dBc and calibration can reduce or completely remove the LO
feed through.
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System Examples (continued)
DLL
115
115
Optional (100 ohm)
Filter Network
634
634
opt.
PLL
1000 MHz
250 MHz
RF OUT
90
0
TRF3703-33 AQM
375 MHz Min to 2380 MHz Max
(Depends on divider and
“dash #” of TRF3761)
Loop
Filter
100
PLL/
DLL
CLKIN/C
100
634
634
DAC-B
DCLKP/N
100
115
115
DAC-A
CMIX1
I-FIR1
CMIX0
I-FIR0
100
Q-FIR1
SYNCP/N
100
FIFO & Demux
D0P/N
DAC5682Z DAC
100
Q-FIR0
Q
LVDS Data Interface
GC5016 or GC5316 DUC,
With GC115 CFR and/or
DPD Processor
D15P/N
I
5V
Interleaved
I/Q Data
FPGA
Div
1/2/4
VCXO
÷4
÷1
VCO
NDivider
Clock Divider /
Distribution
PLL
VCTRL_IN
Loop
Filter
Loop
Filter
PFD
RDiv
CDCM7005
10 MHz
OSC
Note : For clarity, only signal paths are shown .
CPOUT
TRF3761-X PLL/VCO
Figure 51. System Diagram of Direct Conversion Radio
9.3.5 CMTS/VOD Transmitter
The exceptional SNR of the DAC5682Z enables a dual-cable modem termination system (CMTS) or video on
demand (VOD) QAM transmitter in excess of the stringent DOCSIS specification, with >74 dBc and 75 dBc in the
adjacent and alternate channels.
Refer to Figure 50 for an example Dual Channel Real IF Output Radio – this signal chain is nearly identical to a
typical system using the DAC5682Z for a cost optimized dual channel two QAM transmitter. A GC5016 would
take four separate symbol rate inputs and provide pulse shaping and interpolation to ~ 128 MSPS. The four QAM
carriers would be combined into two groups of two QAM carriers with intermediate frequencies of approximately
30 MHz to 40 MHz. The GC5016 would output two real data streams to one DAC5682Z through an FPGA for
CMOS to LVDS translation. The DAC5682Z would function as a dual-channel device and provide 2x or 4x
interpolation to increase the frequency of the 2nd Nyquist zone image. The two signals are then output through
the two DAC outputs, through a transformer and to an RF upconverter.
9.3.6 High-Speed Arbitrary Waveform Generator
The 1GSPS bandwidth input data bus combined with the 16-bit DAC resolution of the DAC5682Z allows
wideband signal generation for test and measurement applications. In this case, interpolation is not desired by
the FPGA-based waveform generator as it can make use of the full Nyquist bandwidth of up to 500MHz.
FPGA
DAC5682Z DAC
100
DAC-A
D0P/N
100
SYNCP/N
100
FIFO
LVDS Data Interface
D15P/N
DAC-B
Sleep
DCLKP/N
100
DLL
Figure 52. System Diagram of Arbitrary Waveform Generator
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9.4 Initialization Set Up
9.4.1 Recommended Start-up Sequence
The following start-up sequence is recommended to initialize the DAC5682Z:
1. Supply all 1.8 V (CLKVDD, DVDD, VFUSE) voltages simultaneously followed by all 3.3 V (AVDD and
IOVDD) voltages.
2. Provide stable CLKIN/C clock.
3. Toggle RESETB pin for a minimum 25 nSec active low pulse width.
4. Program all desired SIF registers. Set DLL_Restart bit during this write cycle. The CONFIG10 register value
should match the corresponding DCLKP/N frequency range in the Electrical Characteristics table.
5. Provide stable DCLKP/N clock. (This can also be provided earlier in the sequence)
6. Clear the DLL_Restart bit when the DCLKP/N clock is expected to be stable.
7. Verify the status of DLL_Lock and repeat until set to ‘1’. DLL_Lock can be monitored by reading the
STATUS0 register or by monitoring the SDO pin in 3-wire SIF mode. (See description for CONFIG14
SDO_func_sel.)
8. Enable transmit of data by asserting the LVDS SYNCP/N input or setting CONFIG3 SW_sync bit. (See
description for CONFIG3 SW_sync and SW_sync_sel) The SYNC source must be held at a logic ‘1’ to
enable data flow through the DAC. If multiple DAC devices require synchronization, refer to the
"Recommended Multi-DAC Synchronization Procedure" below.
9. Provide data flow to LVDS D[15:0]P/N pins. If using the LVDS SYNCP/N input, data can be input
simultaneous with the logic ‘1’ transition of SYNCP/N.
10 Power Supply Recommendations
It is recommended that the device be powered with the nominal supply voltages as indicated in the
Recommended Operating Conditions.
In most instances the best performance is achieved with LDO supplies. However the supplies may be driven with
direct outputs from a DC-DC switcher as long as the noise performance of the switcher is acceptable.
For an LDO power supply reference, it is best to refer to the DAC5682zEVM.
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11 Layout
11.1 Layout Guidelines
The DAC5682Z EVM layout should be used as a reference for the layout to obtain the best performance. A
sample layout is shown in Figure 53. Some important layout recommendations are:
1. Use a single ground plane. Keep the digital and analog signals on distinct separate sections of the board.
This may be virtually divided down the middle of the device package when doing placement and layout.
2. Keep the analog outputs as far away from the switching clocks and digital signals as possible. This will keep
coupling from the digital circuits to the analog outputs to a minimum.
3. Decoupling caps should be kept close to the power pins of the device.
11.2 Layout Example
Figure 53. Top Layer of DAC5682zEVM Layout
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12 Device and Documentation Support
12.1 Device Support
12.1.1 Third-Party Products Disclaimer
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.
12.1.2 Device Nomenclature
Adjacent Carrier Leakage Ratio (ACLR): Defined for a 3.84Mcps 3GPP W-CDMA input signal measured in a
3.84MHz bandwidth at a 5MHz offset from the carrier with a 12dB peak-to-average ratio.
Analog and Digital Power Supply Rejection Ratio (APSSR, DPSSR): Defined as the percentage error in the
ratio of the delta IOUT and delta supply voltage normalized with respect to the ideal IOUT current.
Differential Nonlinearity (DNL): Defined as the variation in analog output associated with an ideal 1 LSB
change in the digital input code.
Gain Drift: Defined as the maximum change in gain, in terms of ppm of full-scale range (FSR) per °C, from the
value at ambient (25°C) to values over the full operating temperature range.
Gain Error: Defined as the percentage error (in FSR%) for the ratio between the measured full-scale output
current and the ideal full-scale output current.
Integral Nonlinearity (INL): Defined as the maximum deviation of the actual analog output from the ideal output,
determined by a straight line drawn from zero scale to full scale.
Intermodulation Distortion (IMD3, IMD): The two-tone IMD3 or four-tone IMD is defined as the ratio (in dBc) of
the worst 3rd-order (or higher) intermodulation distortion product to either fundamental output tone.
Offset Drift: Defined as the maximum change in DC offset, in terms of ppm of full-scale range (FSR) per °C,
from the value at ambient (25°C) to values over the full operating temperature range.
Offset Error: Defined as the percentage error (in FSR%) for the ratio of the differential output current
(IOUT1–IOUT2) and the mid-scale output current.
Output Compliance Range: Defined as the minimum and maximum allowable voltage at the output of the
current-output DAC. Exceeding this limit may result reduced reliability of the device or adversely affecting
distortion performance.
Reference Voltage Drift: Defined as the maximum change of the reference voltage in ppm per degree Celsius
from value at ambient (25°C) to values over the full operating temperature range.
Spurious Free Dynamic Range (SFDR): Defined as the difference (in dBc) between the peak amplitude of the
output signal and the peak spurious signal.
Signal to Noise Ratio (SNR): Defined as the ratio of the RMS value of the fundamental output signal to the
RMS sum of all other spectral components below the Nyquist frequency, including noise, but excluding the first
six harmonics and dc.
12.2 Trademarks
All trademarks are the property of their respective owners.
12.3 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
Submit Documentation Feedback
Copyright © 2007–2015, Texas Instruments Incorporated
Product Folder Links: DAC5682Z
57
DAC5682Z
SLLS853F – AUGUST 2007 – REVISED JANUARY 2015
www.ti.com
12.4 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
13 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
58
Submit Documentation Feedback
Copyright © 2007–2015, Texas Instruments Incorporated
Product Folder Links: DAC5682Z
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
DAC5682ZIRGC
ACTIVE
VQFN
RGC
64
250
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC5682ZI
DAC5682ZIRGCR
ACTIVE
VQFN
RGC
64
2000
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC5682ZI
DAC5682ZIRGCT
ACTIVE
VQFN
RGC
64
250
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 85
DAC5682ZI
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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