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AMC7836
SLAS986D – NOVEMBER 2014 – REVISED FEBRUARY 2018
AMC7836 High-Density, 12-Bit Analog Monitor and Control Solution With Multichannel
ADC, Bipolar DACs, Temperature Sensor, and GPIO Ports
1 Features
3 Description
•
The AMC7836 is a highly-integrated, low-power,
analog monitoring and control solution. The device
includes a 21-channel, 12-bit analog-to-digital
converter (ADC), sixteen 12-bit digital-to-analog
converters (DACs) with programmable output ranges,
eight GPIOs, an internal reference, and a local
temperature-sensor channel. The high level of
integration significantly reduces component count and
simplifies closed-loop system designs making it ideal
for multichannel applications where board space,
size, and low-power are critical.
•
•
•
•
•
•
•
16 Monotonic 12-Bit DACs
– Selectable Ranges: –10 V to 0 V, –5 V to 0 V,
0 V to 5 V, and 0 V to 10 V
– High Current Drive Capability: up to ±15 mA
– Auto-Range Detector
– Selectable Clamp Voltage
12-Bit SAR ADC
– 21 External Analog Inputs
– 16 Bipolar Inputs: –12.5 V to +12.5 V
– 5 High-Precision Inputs: 0 V to 5 V
– Programmable Out-of-Range Alarms
Internal 2.5-V Reference
Internal Temperature Sensor
– –40°C to +125°C Operation
– ±2.5°C Accuracy
Eight General-Purpose I/O Ports (GPIOs)
Low-Power SPI-Compatible Serial Interface
– 4-Wire Mode, 1.8-V to 5.5-V Operation
Operating Temperature: –40°C to +125°C
Available in 64-Pin HTQFP PowerPAD™ IC
Package
The low-power, very high-integration and wide
operating-temperature range of the device make it
suitable as an all-in-one, low-cost, bias-control circuit
for the power amplifiers (PA) found in multichannel
RF communication systems. The flexible DAC output
ranges allow the device to be used as a biasing
solution for a large variety of transistor technologies,
such as LDMOS, GaAs, and GaN. The AMC7836
feature set is similarly beneficial in general-purpose
monitor and control systems.
For applications that require a different channelcount, additional features, or converter resolutions,
Texas Instruments offers a complete family of analog
monitor and control (AMC) products. For more
information, go to www.ti.com/amc.
Device Information(1)
2 Applications
PART NUMBER
AMC7836
PACKAGE
HTQFP (64)
BODY SIZE (NOM)
10.00 mm × 10.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
AMC7836
MUX
2.5-V Reference
5 Unipolar
Analog Inputs
•
•
Communications Infrastructure:
– Cellular Base Stations
– Microwave Backhaul
– Optical Networks
General-Purpose Monitor and Control
Data Acquisition Systems
16 Bipolar
Analog Inputs
•
ADC
DAC-0
16 Bipolar
Analog Outputs
1
Temperature
Sensor
SPI
SPI
DAC-15
GPIO Control
8 GPIOs
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.
AMC7836
SLAS986D – NOVEMBER 2014 – REVISED FEBRUARY 2018
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
7
6.1
6.2
6.3
6.4
6.5
6.6
Absolute Maximum Ratings ...................................... 7
ESD Ratings.............................................................. 7
Recommended Operating Conditions....................... 8
Thermal Information .................................................. 8
Electrical Characteristics: DAC ................................ 9
Electrical Characteristics: ADC and Temperature
Sensor...................................................................... 11
6.7 Electrical Characteristics: General .......................... 12
6.8 Timing Requirements .............................................. 13
6.9 Typical Characteristics: DAC .................................. 15
6.10 Typical Characteristics: ADC ................................ 21
6.11 Typical Characteristics: Reference ....................... 23
6.12 Typical Characteristics: Temperature Sensor....... 23
7
Detailed Description ............................................ 24
7.1 Overview ................................................................. 24
7.2 Functional Block Diagram ....................................... 25
7.3
7.4
7.5
7.6
8
Feature Description.................................................
Device Functional Modes........................................
Programming...........................................................
Register Maps .........................................................
26
40
43
45
Application and Implementation ........................ 72
8.1 Application Information............................................ 72
8.2 Typical Application ................................................. 75
9
Power Supply Recommendations...................... 78
9.1 Device Reset Options ............................................. 79
10 Layout................................................................... 79
10.1 Layout Guidelines ................................................. 79
10.2 Layout Example .................................................... 80
11 Device and Documentation Support ................. 81
11.1
11.2
11.3
11.4
11.5
11.6
Documentation Support ........................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
81
81
81
81
81
81
12 Mechanical, Packaging, and Orderable
Information ........................................................... 81
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision C (April 2016) to Revision D
Page
•
Changed 4.5 V to 4.7 V in AVDD description in Pin Functions .............................................................................................. 5
•
Changed 4.5 V to 4.7 V in DVDD description in Pin Functions .............................................................................................. 6
•
Changed Supply voltage, AVDD MIN value from 4.5 V to 4.7 V ............................................................................................ 8
•
Changed Supply voltage, DVDD MIN value from 4.5 V to 4.7 V ............................................................................................ 8
•
Changed Supply voltage, AVCC MIN value from 4.5 V to 4.7 V ............................................................................................ 8
•
Changed AVDD = DVDD = 4.5 to 5.5 V to AVDD = DVDD = 4.7 to 5.5 V in Electrical Characteristics: DAC conditions ............ 9
•
Changed AVDD = DVDD = 4.5 to 5.5 V to AVDD = DVDD = 4.7 to 5.5 V in Electrical Characteristics: ADC and
Temperature Sensor conditions .......................................................................................................................................... 11
•
Changed AVDD = DVDD = 4.5 to 5.5 V to AVDD = DVDD = 4.7 to 5.5 V in Electrical Characteristics: General conditions .... 12
•
Changed AVDD = DVDD = 4.5 to 5.5 V to AVDD = DVDD = 4.7 to 5.5 V in Timing Requirements conditions ........................ 13
•
Changed operating output range to auto-range detector output range in first sentence in DAC Clear Operation section.. 29
•
Added paragraph and Figure 59 to Internal Reference section ........................................................................................... 38
•
Changed 4.5 V to 4.7 V in All-Negative DAC Range Mode section .................................................................................... 41
•
Added paragraph to Power Supply Recommendations section .......................................................................................... 78
•
Added paragraph to Power Supply Recommendations section .......................................................................................... 79
Changes from Revision B (February 2015) to Revision C
•
2
Page
Changed Figure 117; corrected pins 63 and 64 ................................................................................................................... 75
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SLAS986D – NOVEMBER 2014 – REVISED FEBRUARY 2018
Changes from Revision A (November 2014) to Revision B
•
Page
Changed device status from Product Preview to Production Data ....................................................................................... 1
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AMC7836
SLAS986D – NOVEMBER 2014 – REVISED FEBRUARY 2018
www.ti.com
5 Pin Configuration and Functions
DGND
DVDD
DAC_D15
DAC_D14
AVSSD
DAC_D13
DAC_D12
AVCC_CD
AGND3
DAC_C11
DAC_C10
AVSSC
DAC_C9
DAC_C8
AVDD
REF_CMP
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
PAP Package
64-Pin HTQFP With Exposed Thermal Pad
Top View
GPIO2/ADCTRIG
9
40
ADC_7
GPIO3/DAV
10
39
LV_ADC16
GPIO4
11
38
LV_ADC17
GPIO5
12
37
LV_ADC18
GPIO6
13
36
LV_ADC19
GPIO7
14
35
LV_ADC20
DAC_A0
15
34
ADC_8
DAC_A1
16
33
ADC_9
4
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32
ADC_6
ADC_10
41
31
8
ADC_11
GPIO0/ALARMOUT
30
ADC_5
ADC_12
42
29
7
ADC_13
GPIO0/ALARMIN
28
ADC_4
ADC_14
43
27
6
ADC_15
CS
26
ADC_3
DAC_B7
44
25
5
DAC_B6
SCLK
24
ADC_2
AVSSB
45
23
4
DAC_B5
SDI
22
ADC_1
DAC_B4
46
21
3
AGND1
SDO
20
ADC_0
AVCC_AB
47
19
2
DAC_A3
RESET
18
AGND2
DAC_A2
48
17
1
AVEE
IOVDD_
Copyright © 2014–2018, Texas Instruments Incorporated
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SLAS986D – NOVEMBER 2014 – REVISED FEBRUARY 2018
Pin Functions
PIN
DESCRIPTION
NAME
NO.
I/O
ADC_0
47
I
ADC_1
46
I
ADC_2
45
I
ADC_3
44
I
ADC_4
43
I
ADC_5
42
I
ADC_6
41
I
ADC_7
40
I
ADC_8
34
I
ADC_9
33
I
ADC_10
32
I
ADC_11
31
I
ADC_12
30
I
ADC_13
29
I
ADC_14
28
I
ADC_15
27
I
AGND1
21
I
AGND2
48
I
AGND3
56
I
AVCC_AB
20
I
Positive analog power for DAC groups A and B. The AVCC_AB and AVCC_CD pins must be
connected to the same potential (AVCC).
AVCC_CD
57
I
Positive analog power for DAC groups C and D. The AVCC_AB and AVCC_CD pins must be
connected to the same potential (AVCC).
AVDD
50
I
Analog supply voltage (4.7 V to 5.5 V). This pin must have the same value as the DVDD pin.
Bipolar analog inputs. These pins are typically used to monitor the DAC group-C outputs. The
input range of these channels is –12.5 to 12.5 V.
Bipolar analog inputs. These pins are typically used to monitor the DAC group-D outputs. The
input range of these channels is –12.5 to 12.5 V.
Bipolar analog inputs. These pins are typically used to monitor the DAC group-B outputs. The
input range of these channels is –12.5 to 12.5 V.
Bipolar analog inputs. These pins are typically used to monitor the DAC group-A outputs. The
input range of these channels is –12.5 to 12.5 V.
Analog ground. These pins are the ground reference point for all analog circuitry on the device.
Connect the AGND1, AGND2, and AGND3 pins to the same potential (AGND). Ideally, the
analog and digital grounds should be at the same potential (GND) and must not differ by more
than ±0.3 V.
AVEE
17
I
Lowest potential in the system. This pin is typically tied to a negative supply voltage but if all
DACs are set in a positive output range, this pin can be connected to the analog ground. This
pin also acts as the negative analog supply for DAC group A. This pin sets the power-on-reset
and clamp voltage values for the DAC group A.
AVSSB
24
I
Negative analog supply for DAC group B. This pin sets the power-on-reset and clamp voltage
values for the DAC group B. This pin is typically tied to the AVEE pin for the negative output
ranges or AGND for the positive output ranges.
AVSSC
53
I
Negative analog supply for DAC group C. This pin sets the power-on-reset and clamp voltage
values for the DAC group C. This pin is typically tied to the AVEE pin for the negative output
ranges or AGND for the positive output ranges.
AVSSD
60
I
Negative analog supply for DAC group D. This pin sets the power-on-reset and clamp voltage
values for the DAC group D. This pin is typically tied to the AVEE pin for the negative output
ranges or AGND for the positive output ranges.
CS
6
I
Active-low serial-data enable. This input is the frame-synchronization signal for the serial data.
When this signal goes low, it enables the serial interface input shift register.
DAC_A0
15
O
DAC_A1
16
O
DAC_A2
18
O
DAC_A3
19
O
DAC_B4
22
O
DAC_B5
23
O
DAC_B6
25
O
DAC_B7
26
O
DAC group A. These DAC channels share the same range and clamp voltage. If any of the
other DAC groups is in a negative voltage range, DAC group A should be in a negative
voltage range as well.
DAC group B. These DAC channels share the same range and clamp voltage.
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Pin Functions (continued)
PIN
NAME
DESCRIPTION
NO.
I/O
DAC_C8
51
O
DAC_C9
52
O
DAC_C10
54
O
DAC_C11
55
O
DAC_D12
58
O
DAC_D13
59
O
DAC_D14
61
O
DAC_D15
62
O
DGND
64
I
Digital ground. This pin is the ground reference point for all digital circuitry on the device.
Ideally, the analog and digital grounds should be at the same potential (GND) and must not
differ by more than ±0.3 V.
DVDD
63
I
Digital supply voltage (4.7 V to 5.5 V). This pin must have the same value as the AVDD pin.
GPIO0/ALARMIN
GPIO0/ALARMOUT
GPIO2/ADCTRIG
7
8
9
DAC group C. These DAC channels share the same range and clamp voltage.
DAC group D. These DAC channels share the same range and clamp voltage.
I/O
General-purpose digital I/O 0 (default). This pin is a bidirectional digital input/output (I/O) with
an internal 48-kΩ pullup resistor to the IOVDD pin. Alternatively the pin can be set to operate
as the digital input ALARMIN which is an active-low alarm-control signal. If unused this pin can
be left floating.
I/O
General purpose digital I/O 1 (default). This pin is a bidirectional digital I/O with an internal 48kΩ pullup resistor to the IOVDD pin. Alternatively the pin can be set to operate as ALARMOUT
which is an open drain global alarm output. This pin goes low (active) when an alarm event is
detected. If unused this pin can be left floating.
I/O
General purpose digital I/O 2 (default). This pin is a bidirectional digital I/O with internal 48-kΩ
pullup resistor to the IOVDD pin. Alternatively the pin can be set to operate as ADCTRIG which
is an active-low external conversion trigger. The falling edge of this pin begins the sampling
and conversion of the ADC. If unused this pin can be left floating.
General purpose digital I/O 3 (default). This pin is a bidirectional digital I/O with internal 48-kΩ
pullup resistor to the IOVDD pin. Alternatively the pin can be set to operate as DAV which is an
active-low data-available indicator output. In direct mode, the DAV pin goes low (active) when
the conversion ends. In auto mode, a 1-µs pulse (active low) appears on this pin when a
conversion cycle finishes. The DAV pin remains high when deactivated. If unused this pin can
be left floating.
GPIO3/DAV
10
I/O
GPIO4
11
I/O
GPIO5
12
I/O
GPIO6
13
I/O
GPIO7
14
I/O
IOVDD
1
I
LV_ADC16
39
I
LV_ADC17
38
I
LV_ADC18
37
I
LV_ADC19
36
I
LV_ADC20
35
I
REF_CMP
49
O
Internal-reference compensation-capacitor connection. Connect a 4.7-μF capacitor between
this pin and the AGND2 pin.
RESET
2
I
Active-low reset input. Logic low on this pin causes the device to perform a hardware reset.
SCLK
5
I
Serial interface clock.
SDI
4
I
Serial-interface data input. Data is clocked into the input shift register on each rising edge of
the SCLK pin.
SDO
3
O
Serial-interface data output. The SDO pin is in high impedance when the CS pin is high. Data
is clocked out of the input shift register on each falling edge of the SCLK pin.
Thermal Pad
—
I
The thermal pad is located on the bottom-side of the device package. The thermal pad should
be tied to the same potential as the AVEE pin or left disconnected.
6
General purpose digital I/O. These pins are bidirectional digital I/Os with an internal 48-kΩ
pullup resistor to the IOVDD pin. If unused these pins can be left floating.
I/O supply voltage (1.8 V to 5.5 V). This pin sets the I/O operating voltage and threshold levels.
The voltage on this pin must not be greater than the value of the DVDD pin.
General purpose analog inputs. These channels are used for general monitoring. The input
range of these pins is 0 to 2 × Vref.
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SLAS986D – NOVEMBER 2014 – REVISED FEBRUARY 2018
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)
Supply Voltage
Pin Voltage
(1)
MIN
MAX
AVDD to GND
–0.3
6
DVDD to GND
–0.3
6
IOVDD to GND
–0.3
6
AVCC to GND
–0.3
18
AVEE to GND
–13
0.3
AVSSB, AVSSC, AVSSD to AVEE
–0.3
13
AVCC to AVSSB, AVSSC, or AVSSD
–0.3
26
AVCC to AVEE
–0.3
26
DGND to AGND
–0.3
0.3
ADC_[0-15] analog input voltage to GND
–13
13
LV_ADC[16-20] analog input voltage to GND
–0.3
AVDD + 0.3
DAC_A[0-3] outputs to GND
AVEE – 0.3
AVCC + 0.3
DAC_B[4-7] outputs to GND
AVSSB – 0.3
AVCC + 0.3
DAC_C[8-11] outputs to GND
AVSSC – 0.3
AVCC + 0.3
DAC_D[12-15] outputs to GND
AVSSD – 0.3
AVCC + 0.3
UNIT
V
V
REF_CMP to GND
–0.3
AVDD + 0.3
CS, SCLK, SDI and RESET to GND
–0.3
IOVDD + 0.3
SDO to GND
–0.3
IOVDD + 0.3
GPIO[0-7] to GND
–0.3
IOVDD + 0.3
ADC_[0:15] analog input current
–10
10
LV_ADC[16:20] analog input current
–10
10
Operating temperature
–40
125
°C
Junction temperature, TJmax
–40
150
°C
Storage temperature, Tstg
–40
150
°C
Pin Current
GPIO[0:7] sinking current
(1)
mA
5
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.
6.2 ESD Ratings
VALUE
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001
V(ESD)
(1)
(2)
Electrostatic discharge
(1)
Charged device model (CDM), per JEDEC specification JESD22C101 (2)
UNIT
±1000
±250
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)
Supply voltage
MIN
NOM
MAX
AVDD
4.7
5
5.5
DVDD (1)
4.7
5
5.5
IOVDD (2)
1.8
AVCC
4.7
12
12.5
AVEE
–12.5
–12
0
AVSSB, AVSSC, AVSSD
AVEE
5.5
UNIT
V
0
Specified operating temperature
–40
25
105
°C
Operating temperature
–40
25
125
°C
(1)
(2)
The value of the DVDD pin must be equal to that of the AVDD pin.
The value of the IOVDD pin must be less than or equal to that of the DVDD pin.
6.4 Thermal Information
AMC7836
THERMAL METRIC (1)
PAP (HTQFP)
UNIT
64 PINS
RθJA
Junction-to-ambient thermal resistance
26.2
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
7.2
°C/W
RθJB
Junction-to-board thermal resistance
9.1
°C/W
ψJT
Junction-to-top characterization parameter
0.2
°C/W
ψJB
Junction-to-board characterization parameter
9
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
0.2
°C/W
(1)
8
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
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SLAS986D – NOVEMBER 2014 – REVISED FEBRUARY 2018
6.5 Electrical Characteristics: DAC
The electrical ratings specified in this section apply to all specifications in this document, unless otherwise noted. These
specifications are interpreted as conditions that do not degrade the device parametric or functional specifications for the life of
the product containing it. AVDD = DVDD = 4.7 to 5.5 V, AVCC = 12 V, IOVDD = 1.8 to 5.5 V, AGND = DGND = 0 V, AVEE =
AVSSB = AVSSC = AVSSD = –12 V (for DAC groups in negative range) or 0 V (for DAC groups in positive ranges), DAC output
range = 0 to 10 V for all groups, no load on the DACs, TA = –40°C to 105°C
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
Measured by line passing through codes 020h and
FFFh. 0 to 10 V and –10 to 0 V ranges
±0.3
±1
Measured by line passing through codes 040h and
FFFh. 0 to 5 V and –5 to 0 V ranges
±0.5
±1.5
Specified monotonic. Measured by line passing
through codes 020h and FFFh. 0 to 10 V and –10 to
0 V ranges
±0.03
±1
Specified monotonic. Measured by line passing
through codes 020h and FFFh. 0 to 5 V and –5 to 0
V ranges
±0.06
±1
TA = 25°C, 0 to 10 V range
±2.5
±20
TA = 25°C, –10 to 0 V range
±2.5
±20
TA = 25°C, 0 to 5 V range
±1.5
±15
TA = 25°C, –5 to 0 V range
±1.5
±15
TA = 25°C, Measured by line passing through codes
020h and FFFh. 0 to 10 V range
±0.25
±5
TA = 25°C, Measured by line passing through codes
040h and FFFh. 0 to 5 V range
±0.25
±5
TA = 25°C, Code 000h, –10 to 0 V range
±1
±25
TA = 25°C, Code 000h, –5 to 0 V range
±1
±25
TA = 25°C, Measured by line passing through codes
020h and FFFh, 0 to 10 V range
±0.01
±0.2
TA = 25°C, Measured by line passing through codes
020h and FFFh, –10 to 0 V range
±0.01
±0.2
TA = 25°C, Measured by line passing through codes
040h and FFFh, 0 to 5 V range
±0.01
±0.2
TA = 25°C, Measured by line passing through codes
040h and FFFh, –5 to 0 V range
±0.01
±0.2
UNIT
DAC DC ACCURACY
Resolution
INL
DNL
TUE
Relative accuracy
Differential nonlinearity
Total unadjusted error (1)
Offset error
Zero-code error
Gain error (1)
Offset temperature coefficient
Zero-code temperature coefficient
Gain temperature coefficient (1)
(1)
12
Bits
0 to 10 V range
±1
0 to 5 V range
±1
–10 to 0 V range
±2
–5 to 0 V range
±2
0 to 10 V range
±2.5
–10 to 0 V range
±2.5
0 to 5 V range
±2.5
–5 to 0 V range
±2.5
LSB
LSB
mV
mV
mV
%FSR
ppm/°C
ppm/°C
ppm/°C
The internal reference contribution not included.
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Electrical Characteristics: DAC (continued)
The electrical ratings specified in this section apply to all specifications in this document, unless otherwise noted. These
specifications are interpreted as conditions that do not degrade the device parametric or functional specifications for the life of
the product containing it. AVDD = DVDD = 4.7 to 5.5 V, AVCC = 12 V, IOVDD = 1.8 to 5.5 V, AGND = DGND = 0 V, AVEE =
AVSSB = AVSSC = AVSSD = –12 V (for DAC groups in negative range) or 0 V (for DAC groups in positive ranges), DAC output
range = 0 to 10 V for all groups, no load on the DACs, TA = –40°C to 105°C
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
DAC OUTPUT CHARACTERISTICS
Set at power-up or reset through auto-range
detection. The output range can be modified after
power-up or reset through the DAC range registers
(address 0x1E through 0x1F). DAC-RANGE = 100b
Full-scale output voltage range (2)
Output voltage settling time
Slew rate
Short circuit current
Load current (3)
–10
0
–5
0
Set at power-up or reset through auto-range
detection. The output range can be modified after
power-up or reset through the DAC range registers
(address 0x1E through 0x1F). DAC-RANGE = 111b
0
5
The output range can be modified after power-up or
reset through the DAC range registers (address 0x1E
through 0x1F). DAC-RANGE = 110b
0
10
The output range can be modified after power-up or
reset through the DAC range registers (address 0x1E
through 0x1F). DAC-RANGE = 101b
Transition: Code 400h to C00h to within ½ LSB, RL =
2 kΩ, CL = 200 pF. 0 to 10 V and –10 to 0 V ranges
10
Transition: Code 400h to C00h to within ½ LSB, RL =
2 kΩ, CL = 200 pF. 0 to 5 V and –5 to 0 V ranges
10
Transition: Code 400h to C00h, 10% to 90%, RL = 2
kΩ, CL = 200 pF. 0 to 10 V and –10 to 0 V ranges
1.25
Transition: Code 400h to C00h, 10% to 90%, RL = 2
kΩ, CL = 200 pF. 0 to 5 V and –5 to 0 V ranges
1.25
Full-scale current shorted to the DAC group AVSS or
AVCC voltage
±45
Source or sink with 1-V headroom from the DAC
group AVCC or AVSS voltage, voltage drop < 25 mV
±15
Source or sink with 300-mV headroom from the DAC
group AVCC or AVSS voltage, voltage drop < 25 mV
±10
Maximum capacitive load (4)
RL = ∞
DC output impedance
Code set to 800h, ±15mA
Power-on overshoot
AVEE = AVSSB = AVSSC = AVSSD = AGND, AVCC = 0
to 12 V, 2-ms ramp
Glitch energy
Transition: Code 7FFh to 800h; 800h to 7FFh
Output noise
TA = 25°C, integrated noise from 0.1 Hz to 10 Hz,
code 800h, includes internal reference noise
µs
V/µs
mA
mA
0
TA = 25°C, 1 kHz, code 800h, includes internal
reference noise
V
10
1
10
1
520
20
nF
Ω
mV
nV-s
nV/√Hz
µVPP
CLAMP OUTPUTS
DAC output range: 0 to 10 V, AVSS = AGND
Clamp output voltage (5)
DAC output range: 0 to 5 V, AVSS = AGND
(3)
(4)
(5)
10
0
DAC output range: –10 to 0 V, AVSS = –12 V
AVSS + 2
DAC output range: –5 to 0 V, AVSS = –6 V
AVSS + 1
Clamp output impedance
(2)
0
8
V
kΩ
The output voltage of each DAC group must not be greater than that of the corresponding AVCC pin (AVCC_AB or AVCC_CD) or lower than
that of the corresponding AVSS pin (AVEE, AVSSB, AVSSC or AVSSD). See the DAC Output Range and Clamp Configuration section for
more details.
If all channels are simultaneously loaded, care must be taken to ensure the thermal conditions for the device are not exceeded.
To be sampled during initial release to ensure compliance; not subject to production testing.
No DAC load to the DAC group AVSS pin.
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6.6 Electrical Characteristics: ADC and Temperature Sensor
The electrical ratings specified in this section apply to all specifications in this document, unless otherwise noted. These
specifications are interpreted as conditions that do not degrade the device parametric or functional specifications for the life of
the product containing it. AVDD = DVDD = 4.7 to 5.5 V, AVCC = 12 V, IOVDD = 1.8 to 5.5 V, AGND = DGND = 0 V, AVEE =
AVSSB = AVSSC = AVSSD = –12 V (for DAC groups in negative range) or 0 V (for DAC groups in positive ranges), DAC output
range = 0 to 10 V for all groups, no load on the DACs, TA = –40°C to 105°C
PARAMETER
TEST CONDITIONS
TYP
MAX
Unipolar input channels
±0.5
±1
Bipolar input channels
±0.5
±1.5
Specified monotonic. All input channels
±0.5
±1
Resolution
Integral nonlinearity
Differential nonlinearity
MIN
UNIT
12
Bits
LSB
LSB
UNIPOLAR ANALOG INPUTS: LV_ADC16 to LV_ADC20
Absolute input voltage range
Full scale input range
Vref measured at REF_CMP pin
AGND – 0.2
AVDD + 0.2
0
2 × Vref
Input capacitance
DC input leakage current
V
34
Unselected ADC input
Offset error
±1
Offset error match
±0.5
Gain error (1)
±0.5
Gain error match
Update time
V
pF
±10
µA
±5
LSB
LSB
±5
LSB
±1
Single unipolar input, temperature sensor disabled
LSB
11.5
µs
BIPOLAR ANALOG INPUTS: ADC_0 to ADC_15
Absolute input voltage range
Full scale input range
–13
13
–12.5
12.5
Input resistance
V
V
175
kΩ
Offset error
±0.25
±5
LSB
Gain error (1)
±0.5
±5
LSB
Update time
Single bipolar input, temperature sensor disabled
34.5
µs
TEMPERATURE SENSOR
Operating range
–40
±1.25
125
°C
±2.5
°C
Accuracy
TA = –40°C to 125°C, AVDD = 5 V
Resolution
LSB size
0.25
°C
Update time
All ADC input channels disabled
256
µs
ADC UPDATE TIME
Internal oscillator frequency
ADC update time
3.7
4
4.3
MHz
All 21 ADC inputs enabled, temperature sensor
disabled.
609.5
µs
All 21 ADC inputs enabled, temperature sensor
enabled.
865.5
µs
INTERNAL REFERENCE (INTERNAL REFERENCE NOT ACCESSIBLE)
Initial accuracy
TA = 25°C
2.4925
Reference temperature coefficient
2.5
2.5075
12
35
ppm/°C
V
±5
mV
INTERNAL ADC REFERENCE BUFFER
Reference buffer offset
(1)
TA = 25°C
Internal reference contribution not included.
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6.7 Electrical Characteristics: General
The electrical ratings specified in this section apply to all specifications in this document, unless otherwise noted. These
specifications are interpreted as conditions that do not degrade the device parametric or functional specifications for the life of
the product containing it. AVDD = DVDD = 4.7 to 5.5 V, AVCC = 12 V, IOVVDD = 1.8 to 5.5 V, AGND = DGND = 0 V, AVEE =
AVSSB = AVSSC = AVSSD = –12 V (for DAC groups in negative range) or 0 V (for DAC groups in positive ranges), DAC output
range = 0 to 10 V for all groups, no load on the DACs, TA = –40°C to 105°C
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
–1.5
V
AVSS DETECTOR
AVSS threshold detector (AVSSTH)
–3.5
DIGITAL LOGIC: GPIO
High-level input voltage
Low-level input voltage
Low-level output voltage
Input impedance
IOVDD = 1.8 to 5.5 V
0.7 × IOVDD
V
IOVDD = 1.8 V
0.45
IOVDD = 2.7 to 5.5 V
0.3 × IOVDD
IOVDD = 1.8 V, I(LOAD) = –2 mA
0.4
IOVDD = 5.5 V, I(LOAD) = –5 mA
0.4
To IOVDD
48
V
V
kΩ
DIGITAL LOGIC: ALL EXCEPT GPIO
High-level input voltage
Low-level input voltage
IOVDD = 1.8 to 5.5 V
0.7 × IOVDD
V
IOVDD = 1.8 V
IOVDD = 2.7 to 5.5 V
High-level output voltage
I(LOAD) = –1 mA
Low-level output voltage
I(LOAD) = 1 mA
0.45
V
0.3 × IOVDD
V
IOVDD – 0.4
V
High impedance leakage
High impedance output
capacitance
0.4
V
±5
µA
10
pF
POWER REQUIREMENTS
IAVDD
AVDD supply current
6
13.5
IAVCC
AVCC supply current
7.5
13.5
IAVSS
AVSS supply current
IAVEE
AVEE supply current
IDVDD
DVDD supply current
1
3
IIOVDD
IOVDD supply current
1.5
15
Power consumption
215
IAVDD
AVDD supply current
2.5
5
IAVCC
AVCC supply current
1
2.5
IAVSS
AVSS supply current
IAVEE
AVEE supply current
IDVDD
DVDD supply current
0.75
1.5
IIOVDD
IOVDD supply current
1.5
15
Power consumption
90
12
No DAC load, all DACs at 800h code and ADC at
the fastest auto conversion rate
Power-down mode
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–13.5
–5
–3.5
–1.75
–5
-3
–3
–1.75
mA
µA
mW
mA
µA
mW
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6.8 Timing Requirements
AVDD = DVDD = 4.7 to 5.5 V, AVCC = 12 V, AVEE = –12 V, AGND = DGND = AVSSB = AVSSC = AVSSD = 0 V, DAC output range
= 0 to 10 V for all groups, no load on the DACs, TA = –40°C to 105°C (unless otherwise noted)
MIN
NOM
MAX
UNIT
SERIAL INTERFACE (1)
ƒ(SCLK)
SCLK frequency
tp
SCLK period (2)
tPH
SCLK pulse width high (2)
tPL
SCLK pulse width low (2)
tsu
SDI setup (2)
th
SDI hold (2)
t(ODZ)
IOVDD = 1.8 to 2.7 V
15
IOVDD = 2.7 to 5.5 V
20
IOVDD = 1.8 to 2.7 V
66.67
IOVDD = 2.7 to 5.5 V
50
IOVDD = 1.8 to 2.7 V
30
IOVDD = 2.7 to 5.5 V
23
IOVDD = 1.8 to 2.7 V
30
IOVDD = 2.7 to 5.5 V
23
IOVDD = 1.8 to 2.7 V
10
IOVDD = 2.7 to 5.5 V
10
IOVDD = 1.8 to 2.7 V
10
IOVDD = 2.7 to 5.5 V
10
SDO driven to tristate (3) (4)
IOVDD = 1.8 to 2.7 V
0
15
IOVDD = 2.7 to 5.5 V
0
9
t(OZD)
SDO tri-state to
driven (3) (4)
IOVDD = 1.8 to 2.7 V
0
23
IOVDD = 2.7 to 5.5 V
0
15
t(OD)
SDO output delay (3) (4)
IOVDD = 1.8 to 2.7 V
0
23
IOVDD = 2.7 to 5.5 V
0
15
tsu(CS)
CS setup (2)
IOVDD = 1.8 to 2.7 V
5
IOVDD = 2.7 to 5.5 V
5
th(CS)
CS hold (2)
IOVDD = 1.8 to 2.7 V
20
IOVDD = 2.7 to 5.5 V
20
t(IAG)
Inter-access gap (2)
IOVDD = 1.8 to 2.7 V
10
IOVDD = 2.7 to 5.5 V
10
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
DIGITAL LOGIC
Reset delay; delay-to-normal operation from reset
100
Power-down recovery time
Clamp shutdown delay
250
µs
70
µs
100
µs
Convert pulse width
20
ns
Reset pulse width
20
ns
2
µs
(5)
ADC WAIT state ; the wait time from when the ADC enters the IDLE state
to when the ADC is ready for trigger
(1)
(2)
(3)
(4)
(5)
Specified by design and characterization. Not tested during production.
See Figure 1 and Figure 2.
SDO loaded with 10 pF load capacitance for SDO timing specifications.
See Figure 2.
Specified by design; not subject to production testing. See the ADC Sequencing section for more details.
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t(IAG)
th(CS)
tsu(CS)
CS
tp
tPL
SCLK
tPH
SDI
Bit 23
Bit 1
Bit 0
th
tsu
Figure 1. Serial Interface Write Timing Diagram
t(ODZ)
t(IAG)
th(CS)
tsu(CS)
CS
tp
tPL
SCLK
tPH
SDI
Bit 23
tsu
Bit 8
th
SDO
Bit 7
t(OZD)
Bit 0
t(OD)
Figure 2. Serial Interface Read Timing Diagram
14
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6.9 Typical Characteristics: DAC
1
1
0.8
0.8
0.6
0.6
0.4
0.4
DNL (LSB)
INL (LSB)
At TA = 25°C (unless otherwise noted)
0.2
0
-0.2
-0.4
-0.8
-1
0
512
1024
A1
B5
C9
D13
1536
2048
A2
B6
C10
D14
2560
3072
A3
B7
C11
D15
3584
Code
A0
B4
C8
D12
-0.6
-0.8
-1
4096
0
512
1024
A1
B5
C9
D13
1536
2048
A2
B6
C10
D14
2560
3072
A3
B7
C11
D15
3584
Code
C001
Figure 3. DAC Linearity Error vs Code
DAC Range: 0 to 10 V
4096
C001
Figure 4. DAC Differential Linearity Error vs Code
DAC Range: 0 to 10 V
1
1
0.8
0.8
0.6
0.6
0.4
0.4
DNL (LSB)
INL (LSB)
0
-0.2
-0.4
A0
B4
C8
D12
-0.6
0.2
0
-0.2
-0.4
0.2
0
-0.2
-0.4
A0
B4
C8
D12
-0.6
-0.8
-1
0
512
1024
A1
B5
C9
D13
1536
2048
A2
B6
C10
D14
2560
3072
A3
B7
C11
D15
3584
Code
1
A0
B4
C8
D12
0.8
0.6
A1
B5
C9
D13
A0
B4
C8
D12
-0.6
-0.8
-1
4096
0
512
1024
A1
B5
C9
D13
1536
C001
A2
B6
C10
D14
2048
A2
B6
C10
D14
2560
3072
A3
B7
C11
D15
3584
Code
Figure 5. DAC Linearity Error vs Code
DAC Range: –10 to 0 V
4096
C001
Figure 6. DAC Differential Linearity Error vs Code
DAC Range: –10 to 0 V
1
A3
B7
C11
D15
0.8
0.6
0.4
0.4
DNL (LSB)
INL (LSB)
0.2
0.2
0
-0.2
0.2
0
-0.2
-0.4
-0.4
-0.6
-0.6
-0.8
-0.8
A0
B4
C8
D12
-1
-1
0
512
1024
1536
2048
2560
3072
3584
Code
4096
0
1024
1536
2048
A2
B6
C10
D14
2560
3072
A3
B7
C11
D15
3584
Code
C001
Figure 7. DAC Linearity Error vs Code
DAC Range: 0 to 5 V
512
A1
B5
C9
D13
4096
C001
Figure 8. DAC Differential Linearity Error vs Code
DAC Range: 0 to 5 V
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Typical Characteristics: DAC (continued)
1
1
0.8
0.8
0.6
0.6
0.4
0.4
DNL (LSB)
INL (LSB)
At TA = 25°C (unless otherwise noted)
0.2
0
-0.2
-0.4
-0.8
-1
0
512
1024
A1
B5
C9
D13
1536
2048
A2
B6
C10
D14
2560
3072
A3
B7
C11
D15
3584
A0
B4
C8
D12
-0.6
-0.8
-1
0
512
1024
A1
B5
C9
D13
1536
2048
A2
B6
C10
D14
2560
3072
A3
B7
C11
D15
3584
4096
Code
C001
Figure 9. DAC Linearity Error vs Code
DAC Range: –5 to 0 V
C001
Figure 10. DAC Differential Linearity Error vs Code
DAC Range: –5 to 0 V
1.0
1.0
0.8
0.8
0.6
0.6
0.4
0.4
DNL (LSB)
INL (LSB)
-0.2
4096
Code
0.2
0.0
±0.2
±0.4
0.2
0.0
±0.2
±0.4
±0.6
±0.6
INL MAX
±0.8
-40 -25 -10
5
20
35
50
65
80
95
DNL MIN
±1.0
110 125
TA (ƒC)
DNL MAX
±0.8
INL MIN
±1.0
-40 -25 -10
5
20
35
50
65
80
95
110 125
TA (ƒC)
C001
Figure 11. DAC Linearity Error vs Temperature
DAC Range: 0 to 10 V
C001
Figure 12. DAC Differential Linearity Error vs Temperature
DAC Range: 0 to 10 V
1.0
1.0
0.8
0.8
0.6
0.6
0.4
0.4
DNL (LSB)
INL (LSB)
0
-0.4
A0
B4
C8
D12
-0.6
0.2
0.0
±0.2
±0.4
0.2
0.0
±0.2
±0.4
±0.6
±0.6
INL MAX
±0.8
-40 -25 -10
5
20
35
50
65
80
95
DNL MIN
±1.0
110 125
TA (ƒC)
DNL MAX
±0.8
INL MIN
±1.0
-40 -25 -10
5
20
35
50
TA (ƒC)
C001
Figure 13. DAC Linearity Error vs Temperature
DAC Range: –10 to 0 V
16
0.2
65
80
95
110 125
C001
Figure 14. DAC Differential Linearity Error vs Temperature
DAC Range: –10 to 0 V
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Typical Characteristics: DAC (continued)
1.5
1.0
1.2
0.8
0.9
0.6
0.6
0.4
DNL (LSB)
INL (LSB)
At TA = 25°C (unless otherwise noted)
0.3
0.0
±0.3
±0.6
±0.2
±0.6
INL MAX
±1.2
-40 -25 -10
5
20
35
50
65
80
95
DNL MIN
±1.0
110 125
TA (ƒC)
DNL MAX
±0.8
INL MIN
±1.5
-40 -25 -10
5
20
35
50
65
80
95
110 125
TA (ƒC)
C001
Figure 15. DAC Linearity Error vs Temperature
DAC Range: 0 to 5 V
C001
Figure 16. DAC Differential Linearity Error vs Temperature
DAC Range: 0 to 5 V
1.5
1.0
1.2
0.8
0.9
0.6
0.6
0.4
DNL (LSB)
INL (LSB)
0.0
±0.4
±0.9
0.3
0.0
±0.3
±0.6
0.2
0.0
±0.2
±0.4
±0.9
±0.6
INL MAX
±1.2
-40 -25 -10
5
20
35
50
65
80
95
-40 -25 -10
20
DAC Zero Code Error (mV)
25
3
2
1
0
±1
±2
±3
0V to 10V Range
±4
35
50
65
80
95
80
95
110 125
C001
15
10
5
0
±5
±10
±15
-10V to 0V Range
-5V to 0V Range
-40 -25 -10
5
20
35
50
65
80
95
110 125
TA (ƒC)
C001
Figure 19. DAC Offset Error vs Temperature
65
±25
110 125
TA (ƒC)
50
±20
0V to 5V Range
±5
35
Figure 18. DAC Differential Linearity Error vs Temperature
DAC Range: –5 to 0 V
4
20
20
TA (ƒC)
5
5
5
C001
Figure 17. DAC Linearity Error vs Temperature
DAC Range: –5 to 0 V
-40 -25 -10
DNL MIN
±1.0
110 125
TA (ƒC)
DNL MAX
±0.8
INL MIN
±1.5
DAC Offset Error (mV)
0.2
C001
Figure 20. DAC Zero Code Error vs Temperature
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Typical Characteristics: DAC (continued)
At TA = 25°C (unless otherwise noted)
10
0.20
9
8
0.10
DAC Output (V)
DAC Gain Error (%FSR)
0.15
0.05
0.00
±0.05
0V to 10V Range
±0.10
±0.15
-40 -25 -10
5
20
35
50
65
6
5
4
3
0V to 5V Range
2
-10V to 0V Range
1
-5V to 0V Range
±0.20
7
80
95
0
-50
110 125
TA (ƒC)
-40
-30
-20
-10
0
10
20
30
40
ILOAD (mA)
C001
50
C001
Code 0x800, DAC range: 0 to 10 V
Figure 22. DAC Output Voltage vs Load Current
0.25
9.95
0.2
DAC Output (V)
DAC Output (V)
Figure 21. DAC Gain Error vs Temperature
10
9.9
9.85
9.8
0.15
0.1
0.05
9.75
0
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
ILOAD (mA)
-15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2 -1
ILOAD (mA)
C001
Code 0xFFF, DAC range: 0 to 10 V, AVCC = 10 V, AVEE = 0 V
Code 0x000, DAC range: 0 to 10 V, AVCC = 10 V, AVEE = 0 V
Figure 23. DAC Source Current
Figure 24. DAC Sink Current
15
15
10nF, Rising Edge
200pF, Falling Edge
10
DAC Output Error (LSB)
DAC Output Error (LSB)
10nF, Falling Edge
200pF, Rising Edge
10
5
0
-5
-10
5
0
-5
-10
-15
-15
0
5
10
15
20
Time (µs)
25
0
Figure 25. DAC Settling Time vs Load Capacitance
5
10
15
20
Time (µs)
C001
Code 0x400 to 0xC00 to within ½ LSB
18
0
C001
25
C001
Code 0xC00 to 0x400 to within ½ LSB
Figure 26. DAC Settling Time vs Load Capacitance
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Typical Characteristics: DAC (continued)
At TA = 25°C (unless otherwise noted)
5000
10
15
9
5
3000
2000
6
3
0
0
±3
±6
±5
1000
±9
DAC OUTPUT
±12
AVCC
±10
0
10
100
1k
10k
100k
1M
1
3
4
5
C002
Figure 28. DAC Power On Overshoot, Single Supply
0
10
-2
DAC Output (V)
5
0
-5
AVCC
AVSS
DVDD/AVDD
DAC output
-4
-6
-8
-10
0
1
2
-12
-12.5
3
Time (ms)
-10
-7.5
2.5
±5
0.0
±10
±2.5
DAC Output
Figure 30. DAC Clamp Output vs AVSS
DVDD/AVDD
AVCC
AVSS
IOVDD
DAC OUT
10
5
Voltage (V)
0
0
C020
15
DAC Output Small Signal (mV)
5.0
-2.5
No load
Figure 29. DAC Power On Overshoot, Dual Supply
5
-5
AVSS (V)
C001
AVSS = AVEE = –12 V, AVCC = 0 to 12 V, 2-ms ramp
DAC Output (V)
2
AVSS = AVEE = AGND, AVCC = 0 to 12 V, 2-ms ramp
15
±1
0
Time (ms)
Figure 27. DAC Output Noise vs Frequency
-15
-1
C001
Code 0x800
Voltage (V)
±15
-2
10M
Frequency (Hz)
-10
AVCC (V)
DAC output (mV)
'$& 2XWSXW 1RLVH Q9 ¥+]
12
4000
0
-5
-10
DAC Output Small Signal
±15
±5.0
-5
0
5
10
15
20
25
30
Time (µs)
-15
-0.25
35
0
0.25
0.5
0.75
1
1.25
1.5
C031
Time (ms)
Code 0xFFF, DAC range: –10 to 0 V, no load
Figure 31. DAC Clamp Recovery
C001
Code 0xFFF, DAC range: –10 to 0 V, no load
Figure 32. DAC Output With AVDD and DVDD Supply
Collapse
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Typical Characteristics: DAC (continued)
At TA = 25°C (unless otherwise noted)
15
15
DVDD/AVDD
AVCC
AVSS
IOVDD
DAC OUT
10
10
5
Voltage (V)
5
Voltage (V)
DVDD/AVDD
AVCC
AVSS
IOVDD
DAC OUT
0
0
-5
-5
-10
-10
-15
-0.25
0
0.25
0.5
0.75
1
1.25
Time (ms)
-15
-0.25
1.5
0
0.25
0.5
0.75
1
1.25
Time (ms)
C001
Code 0xFFF, DAC range: –10 to 0 V, no load
1.5
C001
Code 0xC00, DAC range: –10 to 0 V, no load
Figure 33. DAC Output With IOVDD Supply Collapse
Figure 34. DAC Output With AVSS Supply Collapse
15
DVDD/AVDD
AVCC
AVSS
IOVDD
DAC OUT
10
Voltage (V)
5
0
-5
-10
-15
-0.25
0
0.25
0.5
0.75
1
1.25
Time (ms)
1.5
C001
Code 0xFFF, DAC range: –10 to 0 V, no load
Figure 35. DAC Output With AVCC Supply Collapse
20
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6.10 Typical Characteristics: ADC
1.0
1.0
0.8
0.8
0.6
0.6
0.4
0.4
DNL (LSB)
INL (LSB)
At TA = 25°C (unless otherwise noted)
0.2
0.0
±0.2
±0.4
±0.6
±0.6
±0.8
±0.8
±1.0
0
512
1024
1536
2048
2560
3072
3584
4096
Code
0
512
1024
1536
2048
2560
3072
3584
4096
Code
C001
Figure 36. ADC Linearity Error vs Code
Unipolar Input
C001
Figure 37. ADC Differential Linearity Error vs Code
Unipolar Input
1.5
1.0
1.2
0.8
0.9
0.6
0.6
0.4
DNL (LSB)
INL (LSB)
0.0
±0.2
±0.4
±1.0
0.3
0.0
±0.3
0.2
0.0
±0.2
±0.6
±0.4
±0.9
±0.6
±1.2
±0.8
±1.0
±1.5
0
512
1024
1536
2048
2560
3072
3584
0
4096
Code
512
1024
1536
2048
2560
3072
3584
4096
Code
C001
C001
Figure 39. ADC Differential Linearity Error vs Code
Bipolar Input
Figure 38. ADC Linearity Error vs Code
Bipolar Input
1.0
1.0
0.8
0.8
0.6
0.6
0.4
0.4
DNL (LSB)
INL (LSB)
0.2
0.2
0.0
±0.2
±0.4
0.2
0.0
±0.2
±0.4
±0.6
±0.6
INL MAX
±0.8
±1.0
-40 -25 -10
5
20
35
50
65
80
95
DNL MIN
±1.0
110 125
TA (ƒC)
DNL MAX
±0.8
INL MIN
-40 -25 -10
Figure 40. ADC Linearity Error vs Temperature
Unipolar Input
5
20
35
50
65
80
95
110 125
TA (ƒC)
C001
C001
Figure 41. ADC Differential Linearity Error vs Temperature
Unipolar Input
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Typical Characteristics: ADC (continued)
1.5
1.0
1.2
0.8
0.9
0.6
0.6
0.4
0.3
0.2
INL (LSB)
INL (LSB)
At TA = 25°C (unless otherwise noted)
0.0
±0.3
±0.6
±0.6
INL MAX
±1.2
-40 -25 -10
5
20
35
50
65
80
95
-40 -25 -10
4
6
3
4
2
Offset Error (LSB)
5
2
0
±2
±4
±6
35
50
65
80
95
95
110 125
C001
1
0
±1
±2
Unipolar
Bipolar
-40 -25 -10
5
20
35
50
65
80
95
110 125
TA (ƒC)
C001
Figure 44. ADC Gain Error vs Temperature
80
±5
110 125
TA (ƒC)
65
±4
Bipolar
±10
50
±3
Unipolar
±8
35
Figure 43. ADC Differential Linearity Error vs Temperature
Bipolar Input
8
20
20
TA (ƒC)
10
5
5
C001
Figure 42. ADC Linearity Error vs Temperature
Bipolar Input
-40 -25 -10
DNL MIN
±1.0
110 125
TA (ƒC)
DNL MAX
±0.8
INL MIN
±1.5
Gain Error (LSB)
±0.2
±0.4
±0.9
22
0.0
C001
Figure 45. ADC Offset Error vs Temperature
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6.11 Typical Characteristics: Reference
At TA = 25°C (unless otherwise noted)
2.505
Reference Voltage (V)
2.504
2.503
2.502
2.501
2.5
2.499
2.498
2.497
2.496
2.495
-40 -25 -10
5
20
35
50
65
80
95
110 125
Temperature (ƒC)
C001
10 units, measured at REF_CMP
Figure 46. Reference Voltage vs Temperature
6.12 Typical Characteristics: Temperature Sensor
At TA = 25°C (unless otherwise noted)
Local Temperature Sensor Error (ƒC)
2.5
2.0
1.5
1.0
0.5
0.0
±0.5
±1.0
±1.5
±2.0
±2.5
±40 ±25 ±10
5
20
35
50
65
80
TA (ƒC)
95
110 125
C001
10 units
Figure 47. Temperature Sensor Error vs Temperature
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7 Detailed Description
7.1 Overview
The AMC7836 device is a highly-integrated analog-monitoring and control solution capable of voltage and
temperature supervision. The AMC7836 device includes the following features:
• Sixteen 12-bit digital-to-analog converters (DACs) with adjustable output ranges
– Output ranges: –10 to 0 V, –5 to 0 V, 0 to 5 V, and 0 to 10 V
– Auto-range detector on device power-up and reset events
– The DACs power-on and clamp voltages can be pin-selected between AGND and a negative voltage
– The DACs can be configured to clamp automatically upon detection of an alarm event
• A multi-channel, 12-bit analog-to-digital converter (ADC) for voltage and temperature sensing
– Sixteen bipolar inputs: –12.5 to 12.5 V input range
– Five precision inputs with programmable threshold detectors: 0 to 5 V input range
– Internal temperature sensor
• Internal 2.5 V precision reference
• Eight general purpose I/O (GPIO) ports
• Communication with the device occurs through a 4-wire SPI-compatible interface supporting 1.8 to 5.5 V
operation
The AMC7836 device is characterized for operation over the temperature range of –40ºC to 125ºC which makes
the device suitable for harsh-condition applications. The device is available in a 10-mm × 10-mm 64-pin HTQFP
PowerPAD IC package.
The very high-integration of the AMC7836 device makes it an ideal all-in-one, low-cost, bias-control circuit for the
power amplifiers (PAs) found in multi-channel RF-communication systems. The flexible DAC output ranges allow
the device to be used as a biasing solution for a large variety of transistor technologies such as LDMOS, GaAs,
and GaN. The AMC7836 feature set is similarly beneficial in general-purpose monitor and control systems.
24
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7.2 Functional Block Diagram
REF_CMP
AMC7836
ADC
Trigger
DAC
Trigger
DAC-0
12-b
Bipolar
Inputs
Scaling
DAC_A12
DAC_A13
DAC_A14
ADC
12-b
LV_ADC16
LV_ADC17
LV_ADC18
LV_ADC19
LV_ADC20
DAC-3
12-b
DAC_A15
DAC-4
12-b
DAC_B8
DAC_B9
DAC_B10
Local
Temperature
Sensor
DAC_B11
DAC-8
12-b
DAC_C0
GPIO
Controller
DAC_C1
DAC_C2
DAC-11
12-b
DAC_C3
DAC-12
12-b
DAC_D4
DAC_D6
DAC-15
12-b
DAC_D7
DGND
AGND3
AGND2
AVDD
AGND1
AVCC_CD
AVCC_AB
SDO
CS
SDI
SCLK
RESET
IOVDD
AVSSC
AVSSD
DAC
Range
and
Clamp
Setup
Serial Interface Register
and Control
AVEE
AVSSB
DVDD
Synchronization
Logic
DAC Group D
DAC_D5
Control, Limits, and
Status Registers
DAC Group C
GPIO0/ALARMIN
GPIO1/ALARMOUT
GPIO2/ADCTRIG
GPIO3/DAV
GPIO4
GPIO5
GPIO6
GPIO7
DAC-7
12-b
DAC Group B
Unipolar ADC Inputs
ADC_0
ADC_1
ADC_2
ADC_3
ADC_4
ADC_5
ADC_6
ADC_7
ADC_8
ADC_9
ADC_10
ADC_11
ADC_12
ADC_13
ADC_14
ADC_15
DAC Group A
Bipolar ADC Inputs
Reference
(2.5 V)
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7.3 Feature Description
7.3.1 Digital-to-Analog Converters (DACs)
The AMC7836 device features an analog-control system centered on sixteen 12-bit DACs that operate from the
internal reference of the device. Each DAC core consists of a string DAC and output-voltage buffer.
The resistor-string structure consists of a series of resistors, each with a value of R. The code loaded to the DAC
determines at which node on the string the voltage is tapped off to be fed into the output amplifier. The voltage is
tapped off by closing one of the switches connecting the string to the amplifier (see Figure 48). This architecture
has inherent monotonicity, voltage output, and low glitch. This architecture is also linear because all the resistors
are of equal value.
R
R
R
To Output
Amplifier
R
R
Figure 48. DAC Resistor String
7.3.1.1 DAC Output Range and Clamp Configuration
The 16 DACs are split into four groups, each with four DACs. All of the DACs in a given group share the same
output range and clamp voltage value, however, these settings can be set independently for each DAC group.
After power-on or a reset event the following actions take place: the DAC outputs are directed automatically to
the corresponding clamp value; the DAC groups output ranges are set by the auto-range detector and; all DAC
data registers and data latches are set to the default values. Figure 49 shows a high level block diagram of each
DAC in the AMC7836 device.
26
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Feature Description (continued)
AVCC
Serial Interface DAC Data Register
WRITE
READ
1
0
DAC
Buffer
Register
READBACK bit
DAC
Active
Register
UPDATE
command
0
Resistor String
0x000
1
DAC
Output Range
Configuration
VO
DAC output
Clear State
(register or alarmgenerated)
Clamp State
(reset event or
DAC power down)
Clamp
Offset
5
» 6 × AVSS
AVSS
Figure 49. DAC Block Diagram
7.3.1.1.1 Auto-Range Detection
After power-on or a reset event the output range for each DAC group is set automatically by the voltage present
in the corresponding AVSS pin (AVEE, AVSSB, AVSSC or AVSSD). When the AVSS voltage of a DAC group is lower
than the threshold value, AVSSTH, the output for that DAC group is automatically configured to the –10 to 0 V
range. Conversely, if the DAC group AVSS voltage is higher than AVSSTH, the DAC-group output is automatically
set to the 0 to 5 V range. The auto-range detector results for each DAC group are stored in the general status
register (address 0x72).
In addition to a power-on or reset event, the auto-range detector is also enabled by a register write to the DAC
power down registers (address 0xB2 through 0xB3) or the device configuration register (address 0x02).
Although the initial output-range setting is determined by the auto-range detector, the output range for each
DAC-group can be afterwards configured to any of the available output ranges (–10 to 0 V, –5 to 0 V, 0 to 5 V, or
0 to 10 V) through the DAC range registers (address 0x1E through 0x1F).
NOTE
The power-on-reset and clamp-voltage value of each DAC group is set by the
corresponding AVSS pin and is independent of the DAC output range. In some
applications, matching the clamp-voltage setting to the operating voltage range is
imperative. For those applications, the recommended connections for the AVSS pin are:
AGND for the positive output ranges, in which case the clamp voltage is 0 V; a negative
supply voltage with a lower value than the minimum DAC output voltage (–5 V or –10 V)
for the selected negative output range, in which case the unloaded clamp voltage is
determined by the value of the negative supply voltage (see Figure 50).
Although not a recommended operating condition, the device allows a DAC group to
operate in a positive output range even if its clamp voltage is negative (AVSS connected to
a negative supply voltage).
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Feature Description (continued)
0
DAC Output (V)
-2
-4
-6
-8
-10
-12
-12.5
-10
-7.5
-5
-2.5
AVSS (V)
0
C020
Figure 50. DAC Clamp Output vs AVSS
A special distinction must be made for DAC group A as the AVSS pin of this group is the dual-function AVEE pin.
Aside from setting the clamp voltage and default output range for the DAC group A, the AVEE pin is also the
lowest potential in the device. As a consequence the AVEE voltage is dependent on the other AVSS pin
connections. The AVEE pin can only be connected to the analog ground if all the other AVSS pins are also
connected to the analog ground. If any of the AVSS pins is connected to a negative voltage, the AVEE pin must
also be connected to that voltage (see Table 1).
The full-scale output range for each DAC group is limited by the corresponding AVCC and AVSS values. The
maximum and minimum outputs cannot exceed the AVCC voltage or be lower than the AVSS voltage, respectively.
Table 1. Recommended DAC Group Configuration
DAC
GROUP
DAC
AUTO-RANGE
AND CLAMP
VOLTAGE
SELECTION
(AVSS)
AVEE = AGND
AVEE = VNEG
OUTPUT RANGE
CLAMP VOLTAGE
CONNECTION
OUTPUT RANGE
CLAMP VOLTAGE
CONNECTION
AVEE
0 to 5 V or 0 to 10 V
AGND
–5 to 0 V or –10 to 0 V
VNEG
–5 to 0 V or –10 to 0 V
VNEG ≤ AVSSB ≤ –5 V
AVSSB
0 to 5 V or 0 to 10 V
AGND
0 to 5 V or 0 to 10 V
AGND
–5 to 0 V or –10 to 0 V
VNEG ≤ AVSSC ≤ –5 V
0 to 5 V or 0 to 10 V
AGND
–5 to 0 V or –10 to 0 V
VNEG ≤ AVSSD ≤ –5 V
0 to 5 V or 0 to 10 V
AGND
DAC_A0
A
DAC_A1
DAC_A2
DAC_A3
DAC_B4
B
DAC_B5
DAC_B6
DAC_B7
DAC_C8
C
DAC_C9
DAC_C10
AVSSC
0 to 5 V or 0 to 10 V
AGND
DAC_C11
DAC_D12
D
DAC_D13
DAC_D14
AVSSD
0 to 5 V or 0 to 10 V
AGND
DAC_D15
28
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7.3.1.2 DAC Register Structure
The input data of the DACs is written to the individual DAC data registers (address 0x50 through 0x6F) in straight
binary format for all output ranges (see Table 2).
Table 2. DAC Data Format
DIGITAL CODE
DAC OUTPUT VOLTAGE (V)
0 to 5 V RANGE
0 to 10 V RANGE
–5 to 0 V RANGE
0000 0000 0000
0
0
–5
–10 to 0 V RANGE
–10
0000 0000 0001
0.00122
0.00244
–4.99878
–9.99756
1000 0000 0000
2.5
5
–2.5
–5
1111 1111 1110
4.99756
9.99512
–0.00244
–0.00488
1111 1111 1111
4.99878
9.99756
–0.00122
–0.00244
Data written to the DAC data registers is initially stored in the DAC buffer registers. The transfer of data from the
DAC buffer registers to the active registers is initiated by an update command in the register update register
(address 0x0F). When the active registers are updated, the DAC outputs change to the new values.
The host has the option to read from either the buffer registers or the active registers when accessing the DAC
data registers. The DAC read back option is configured by the READBACK bit in the interface configuration 1
register (address 0x01).
7.3.1.3 DAC Clear Operation
Each DAC can be set to a CLEAR state using either hardware or software. When a DAC goes to CLEAR state, it
is loaded with a zero-code input and the output voltage is set according to the auto-range detector output range.
The DAC buffer or active registers do not change when the DACs enter the CLEAR state which makes it
possible to return to the same voltage output before the clear event was issued. Even though the contents of the
active register do not change while a DAC is in CLEAR state, a data-register read operation from the active
registers while in this state returns zero-code. This functionality enables the ability to determine the DAC output
voltage regardless of the operating state (CLEAR or NORMAL).
NOTE
The DAC buffer and active registers can be updated while the DACs are in CLEAR state
allowing the DACs to output new values upon return to normal operation. When the DACs
exit the CLEAR state, the DACs are immediately loaded with the data in the DAC active
registers and the output is set back to the corresponding level to restore operation.
The DAC clear registers (address 0xB0 through 0xB1) enable independent control of each DAC CLEAR state
through software. The DACs can also be forced to enter a CLEAR state through hardware using the ALARMIN
pin. See the Programmable Out-of-Range Alarms section for a detailed description of this method.
The ALARMIN-controlled clear mechanism is just a special case of the device capability to force the DACs into
the CLEAR state as a response to an alarm event. To enable this function, the alarm events must first be
enabled as DAC-clear alarm sources in the DAC clear source registers (address 0x1A through 0x1B). The DAC
outputs to be cleared by the selected alarm events must also be specified in the DAC clear enable registers
(address 0x18 through 0x19).
An alarm event sets the corresponding alarm bit in the alarm status registers. In addition all the DACs set to
clear in response to the alarm event in the DAC clear enable registers enter a CLEAR state. Once the alarm bit
is cleared, as long as no other CLEAR-state controlling alarm events have been triggered, the DACs are
reloaded with the contents of the DAC active registers and the outputs update accordingly.
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7.3.2 Analog-to-Digital Converter (ADC)
The AMC7836 features a monitoring system centered on a 12-bit SAR (successive approximation register) ADC
fronted by a 22-channel multiplexer and an on-chip track-and-hold circuit. The monitoring systems is capable of
sensing up to 16 external bipolar inputs (–12.5 to 12.5 V range), five external unipolar inputs (0 to 5 V range),
and an internal analog temperature sensor.
The ADC operates from an internal 2.5 V reference (Vref, measured at the REF_CMP pin) and the input range is
0 V to 2 × Vref. The external bipolar inputs to the ADC are internally mapped to this range. The ADC timing
signals are derived from an on-chip temperature-compensated oscillator. The conversion results can be
accessed through the device serial interface.
7.3.2.1 Analog Inputs
The AMC7836 has 21 analog inputs for external voltage sensing. Sixteen of these inputs (ADC_0 through
ADC_15) are bipolar and the other five (LV_ADC16 through LV_ADC20) are unipolar. Figure 51 shows the
equivalent circuit for the external analog-input pins. All switches are open while the ADC is in the IDLE state.
Scaling Network
3.125 V
R(MUX)
S(W)
RS
C(SAMPLE)
ADC_0
3.125 V
S(W) is closed during acquisition.
S(W) is open during conversion.
ADC_15
AVDD
LV_ADC16
AVDD
LV_ADC20
AGND
Figure 51. ADC External Inputs Equivalent Circuit
To achieve the specified performance, especially at higher input frequencies, driving each analog input pin with a
low impedance source is recommended. An external amplifier can also be used to drive the input pins.
30
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7.3.2.1.1 Bipolar Analog Inputs
The AMC7836 can support up to 16 bipolar analog inputs. The analog input range for these channels is –12.5 to
12.5 V. The bipolar signal is scaled internally through a resistor divider so that it maps to the native input range
of the ADC (0 V to 2 × Vref). The input resistance of the scaling network is 175 kΩ.
The bipolar analog input conversion values are stored in straight binary format in the ADC data registers
(address 0x20 through 0x49). The LSB (least-significant bit) size for these channels is 25 × Vref / 4096. With the
internal reference equal to 2.5 V, the input voltage is calculated by Equation 1.
§ CODE u 5
·
Voltage 5 ¨
2.5 ¸
4096
©
¹
(1)
A typical application for the bipolar channels is monitoring of the 16 DAC outputs in the device. In this application
the bipolar inputs can be driven directly. However, in applications where the signal source has high impedance,
buffering the analog input is recommended. When driven from a low impedance source such as the AMC7836
DAC outputs, the network is designed to settle before the start of conversion. Additional impedance can affect
the settling and divider accuracy of this network.
7.3.2.1.2 Unipolar Analog Inputs
In addition to the bipolar input channels, the AMC7836 device includes five unipolar analog inputs. The analog
input range for these channels is 0 V to 2 × Vref and the LSB size for these channels is 2 × Vref / 4096.
The unipolar analog input conversion values are stored in straight binary format in the ADC-Data registers
(address 0x40 through 0x49). With the internal reference equal to 2.5 V, the input voltage is calculated by
Equation 2.
CODE u 5
Voltage
4096
(2)
In applications where the signal source has high impedance, externally buffering the unipolar analog input is
recommended.
7.3.2.2 ADC Sequencing
The AMC7836 ADC conversion sequence is shown in Figure 52. The ADC supports direct mode and auto mode
conversion. The conversion method is selected in the ADC configuration register (address 0x10). The default
conversion method is direct mode.
In both methods, the single channel or sequence of channels to be converted by the ADC must be first
configured in the ADC MUX configuration registers (address 0x13 through 0x15). The input channels to the ADC
include 16 external bipolar inputs, five external unipolar inputs, and the internal temperature sensor.
In direct-mode conversion, the selected ADC input channels are converted on demand by issuing an ADC trigger
signal. After the last enabled channel is converted, the ADC enters IDLE state and waits for a new trigger.
In auto-mode conversion, the selected ADC input channels are converted continuously. The conversion cycle is
initiated by issuing an ADC trigger. Upon completion of the first conversion sequence another sequence is
automatically started. Conversion of the selected channels occurs repeatedly until the auto-mode conversion is
stopped by issuing a second trigger signal.
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Start
(Reset)
ADC IDLE state
ADC-register
changes?
Yes
ADC WAIT state
(2 µs)
No
No
ADC trigger?
Yes
First conversion
Update registers
and issue data
available indicator
Yes
Yes
Direct mode?
Is this the last
conversion?
No
Yes
ADC trigger?
No
Convert next
channel
No
Figure 52. ADC Conversion Sequence
Regardless of the selected conversion method, the following ADC registers should only be updated while the
ADC is in IDLE state:
• ADC configuration register (address 0x10)
• False alarm configuration register (address 0x11)
• ADC MUX configuration registers (address 0x13 through 0x15)
• Threshold registers (0x80 through 0x97)
• Hysteresis register (0xA0 through 0xA5)
NOTE
After updating any of the ADC registers listed above, a minimum 2 µs wait time should be
implemented before issuing an ADC trigger.
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7.3.2.3 ADC Synchronization
A trigger signal must occur for the ADC to enter and exit the IDLE state. The ADC trigger can be generated
either through software (ICONV bit in the ADC trigger register, 0xC0) or hardware (GPIO2/ADCTRIG, pin 9). To
use the GPIO2/ADCTRIG pin as an ADC trigger, the pin must be configured accordingly in the GPIO
configuration register (address 0x12). When the pin is configured as a trigger, a falling edge on it begins the
sampling and conversion of the ADC.
In auto mode the ADC and temperature data registers (0x20 through 0x4B) are accessed by first issuing an ADC
UPDATE command in the register update register (address 0x0F). The ADC UPDATE command ensures the
latest available data for each input channel can be accessed without the need for complex synchronization
schemes between the AMC7836 device and the host controller. A single ADC UPDATE command updates all
ADC and temperature data registers. Therefore issuing multiple UPDATE commands is not necessary when
reading more than one ADC data register.
NOTE
The ADC UPDATE command and accessing of the ADC and Temperature data registers
does not interfere with the conversion process which ensures continuous ADC operation.
In direct mode the ADC and temperature data registers (0x20 through 0x4B) should only be accessed while the
ADC is in the IDLE state (see Figure 53). Although the total update time can be easily calculated, the device
provides a data-available indicator signal to track the ADC status. Failure to satisfy the synchronization
requirements could lead to erroneous data reads.
The data-available indicator signal is output through the GPIO3/DAV pin and as a data-available flag that is
accessible through the serial interface (DAVF bit in the general status register, 0x72). The GPIO3/DAV pin must
be configured in the GPIO configuration register (address 0x12) as an interrupt. After a direct-mode conversion is
complete and the ADC returns to the IDLE state, the DAVF bit is immediately set to 1 and the DAV pin is active
(low) which indicates that new data is available. The pin and flag are cleared automatically when a new
conversion begins or one of the ADC data or temperature data registers is accessed.
a) Direct Mode, Software Trigger
Trigger
Command
CS
Read
Command
1st internal
trigger
Trigger
Command
2nd internal
trigger
> 2 µs
Read
Command
DAV
First CONVERSION of the channels
specified in the ADC MUX Registers
Second CONVERSION of the channels
specified in the ADC MUX Registers
b) Direct Mode, Hardware Trigger
ADCTRIG
1st trigger
2nd trigger
3rd trigger
> 2 µs
Read
Command
Read
Command
CS
DAV
First CONVERSION of the channels
specified in the ADC MUX Registers
Second CONVERSION of the channels
specified in the ADC MUX Registers
Third CONVERSION of the channels
specified in the ADC MUX Registers
Figure 53. ADC Direct-Mode Trigger Synchronization
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7.3.2.4 Programmable Out-of-Range Alarms
The AMC7836 device is capable of continuously analyzing the five external unipolar inputs and internal
temperature sensor conversion results for normal operation.
Normal operation is established through the lower and upper threshold registers (address 0x80 through 0x97).
When any of the monitored inputs is out of the specified range, an alarm event is issued and the global alarm bit,
GALR in the general status register (0x72), is set (see Figure 54). Use the alarm status registers (0x70 through
0x71) to determine the source of the alarm event.
RESERVED
7
RESERVED
6
RESERVED
5
LV_ADC20 Alarm
4
LV_ADC19 Alarm
3
LV_ADC18 Alarm
2
LV_ADC17 Alarm
1
LV_ADC16 Alarm
0
RESERVED
7
RESERVED
6
RESERVED
5
RESERVED
4
ALARMIN Alarm
3
Die Temperature Alarm
2
Temperature Sensor High Alarm
1
Temperature Sensor Low Alarm
0
ALARM STATUS 0
0x70
GALR
ALARM STATUS 1
0x71
Figure 54. Alarm Status Register
The ALARM-LATCH-DIS bit in the ALARMOUT source 1 register (address 0x1D) sets the latching behavior for
all alarms (except for the ALARMIN alarm which is always unlatched). When the ALARM-LATCH-DIS bit is
cleared to 0 the alarm bits in the alarm status registers are latched. The alarm bits are referred to as being
latched because they remain set until read by software. This design ensures that out-of-limit events cannot be
missed if the software is polling the device periodically. All bits are cleared when reading the alarm status
registers, and all bits are reasserted if the out-of limit condition still exists on the next monitoring cycle, unless
otherwise noted. When the ALARM-LATCH-DIS bit is set to 1, the alarm bits are not latched. The alarm bits in
the alarm status registers are set to 0 when the error condition subsides, regardless of whether the bit is read or
not.
All of the alarms can be set to activate the ALARMOUT pin. To enable this functionality, the GPIO1/ALARMOUT
pin must be configured accordingly in the GPIO configuration register (address 0x12). The ALARMOUT pin
works as an interrupt to the host so that it can query the alarm status registers to determine the alarm source.
Any alarm event can activate the pin as long as the alarm is not masked in the ALARMOUT source registers
(address 0x1C through 0x1D). When an alarm event is masked, the occurrence of the event sets the
corresponding status bit in the alarm status registers, but does not activate the ALARMOUT pin.
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7.3.2.4.1 Unipolar Inputs Out-of-Range Alarms
The AMC7836 device provides out-of-range detection for the five external unipolar ADC inputs (LV_ADC16
through LV_ADC20, pins 35 through 39). Figure 55 shows the out-of-range detection block. When the
measurement is out-of-range, the corresponding alarm bit in the alarm status 0 register (address 0x70) is set to 1
to flag the out-of-range condition. The values in the ADC upper and lower Threshold registers (address 0x80
through 0x93) define the upper and lower bound thresholds for all five inputs.
ADCn-UpperThreshold Value
(upper bound)
±
+
LV_ADCn
Conversion Value
(n = 16 to 20)
ADCn-ALR
Bit
±
ADCn-LowerThreshold Value
(lower bound)
+
Figure 55. Unipolar Inputs Out-of-Range Alarms
7.3.2.4.2 Unipolar Inputs Out-of-Range Alarms
The AMC7836 includes high-limit and low-limit detection for the internal temperature sensor. Figure 56 shows the
temperature detection block. The values in the LT upper and lower threshold registers (address 0x94 through
0x97) set the limits for the temperature sensor. The temperature sensor detector can issue either a high-alarm
(LT-HIGH-ALR bit) or a low-alarm (LT-LOW-ALR bit) in the alarm status 1 register (address 0x71) depending on
whether the high or low thresholds were exceeded. To implement single, upper-bound threshold detection for the
temperature sensor, the host processor can set the upper-bound threshold to the desired value and the lowerbound threshold to the default value. For lower-bound threshold detection, the host processor can set the lowerbound threshold to the desired value and the upper-bound threshold to the default value.
In addition to the programmable threshold alarms the temperature sensor detection circuit also includes a die
thermal-alarm flag which continuously monitors the die temperature. When the die temperatures exceeds 150˚C
the die thermal alarm flag (THERM-ALR bit) in the alarm status 1 register (address 0x71) is set. The internal
temperature sensor must be enabled for this alarm to be functional.
Temperature
High Threshold
(upper bound)
±
LT-HIGH-ALR Bit
+
150°C
±
THERM-ALR Bit
Temperature
Data
+
±
Temperature
Low Threshold
(lower bound)
LT-LOW-ALR Bit
+
Figure 56. Internal Temperature Out-of-Range Alarms
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7.3.2.4.3 ALARMIN Alarm
The AMC7836 device offers the option of using an external interrupt signal, such as the output of a comparator
as an alarm event. The GPIO0/ALARMIN pin is used as the alarm input and must be configured accordingly in
the GPIO configuration register (address 0x12). The pin is active low when configured as an alarm input.
A typical application for ALARMIN pin is to use it as a hardware interrupt that is responsible for forcing one or
more DACs to a CLEAR state. The DAC is loaded with a zero-code input and the output voltage is set according
to the operating output range, however the DAC buffer or active registers do not change (see the Digital-toAnalog Converters (DACs) section for more details). To enable this functionality the ALARMIN pin must be
enabled as a DAC clear-alarm source in the DAC clear source 1 register (address 0x1B). Additionally the DAC
outputs to be cleared by the ALARMIN pin must be specified in the DAC clear enable registers (address 0x18
through 0x19).
In this application when the ALARMIN pin goes low, all the DACs that are set to clear in response to the
ALARMIN alarm in the DAC-clear enable registers enter a CLEAR state. When the ALARMIN pin goes back high
the DACs are reloaded with the contents of the DAC active registers which allows the DAC outputs to return to
the previous operating point without any additional commands.
7.3.2.4.4 Hysteresis
If a monitored signal is out of range and the alarm is enabled, the corresponding alarm bit is set to 1. However,
the alarm condition is cleared only when the conversion result returns either a value lower than the high
threshold register setting or higher than the low threshold register setting by the number of codes specified in the
hysteresis setting (see Figure 57). The ADC and LT hysteresis registers (address 0xA0 through 0xA4) store the
hysteresis value for the external unipolar inputs and internal temperature sensor programmable alarms. The
hysteresis is a programmable value between 0 LSB to 127 LSB for the unipolar inputs alarms and 0°C to 31°C
for the internal temperature-sensor alarms. The die thermal alarm hysteresis is fixed at 8°C.
High Threshold
Hysteresis
Hysteresis
Low Threshold
Over High Alarm
Below Low Alarm
Figure 57. Device Hysteresis
7.3.2.4.5 False-Alarm Protection
To prevent false alarms, an alarm event is only registered when the monitored signal is out of range for an N
number of consecutive conversions. If the monitored signal returns to the normal range before N consecutive
conversions, an alarm event is not issued. The false alarm factor, N, for the unipolar input and local temperature
sensor out-of-range alarms can be configured in the false alarm configuration register (address 0x11).
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7.3.3 Internal Temperature Sensor
The AMC7836 device has an on-chip temperature sensor that measures the device die temperature. The normal
operating temperature range for the internal temperature sensor is limited by the operating temperature range of
the device (–40°C to 125°C).
The temperature sensor results are converted by the device ADC at a lower speed than the analog input
channels. The temperature can be monitored either continuously or as a single-time conversion depending on
whether the ADC is configured in auto mode or direct mode (see the Analog-to-Digital Converter (ADC) section
for more details). If the temperature sensor is not needed, it can be disabled in the ADC MUX configuration 2
register (address 0x15). When disabled, the temperature sensor output is not converted by the ADC.
The temperature sensor provides 0.25°C resolution over the operating temperature range. The temperature
value is stored in 12-bit two’s complement format in the temperature data registers (address 0x78 through 0x79).
Table 3. Temperature Sensor Data Format
TEMPERATURE (°C)
DIGITAL CODE
–40
1111 0110 0000
–25
1111 1001 1100
–10
1111 1101 1000
–0.25
1111 1111 1111
0
0000 0000 0000
0.25
0000 0000 0001
10
0000 0010 1000
25
0000 0110 0100
50
0000 1100 1000
75
0001 0010 1100
100
0001 1001 0000
105
0001 1010 0100
125
0001 1111 0100
Use Equation 3 and Equation 4 to calculate the positive or negative temperature according to the polarity of the
temperature data MSB (0 - positive, 1 - negative).
ADC _ Code
Positive Temperature (qC)
4
(3)
4096 ADC _ Code
Negative Temperature (qC)
(4)
4
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7.3.4 Internal Reference
The AMC7836 device includes a high-performance internal reference for the on-chip ADC and 16 DACs (see
Figure 58). The internal reference is a 2.5 V, bipolar transistor-based, precision bandgap reference. A
compensation capacitor (4.7 μF, typical) should be connected between the REF_CMP pin and the AGND2 pin.
The AMC7836 device includes a buffer to drive the ADC and should not be used to drive any external circuitry.
The ADC reference buffer is powered down by default and should be enabled in the ADC configuration register
(address 0x10) during device initialization.
Internal
Reference
(2.5 V)
C > 4.7 µF
(Minimize
inductance to pin)
REF_CMP
AGND2
DAC-1
12-b
ADC
12-b
Local
Temperatu
re Sensor
DAC Outputs
MUX
Analog Inputs
DAC-0
12-b
DAC-15
12-b
Figure 58. AMC7836 Internal Reference
The internal reference is typically established after power-up in less than 5 ms at TA = 25°C however the
reference settling time is highly dependent on temperature. Figure 59 shows typical reference settling time as a
function of temperature.
Internal Reference Settling Time (ms)
160
140
120
100
80
60
40
20
0
-40
-25
-10
5
20 35 50 65
Temperature (°C)
80
95
110 125
D001
Figure 59. Internal Reference Settling Time vs Temperature
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7.3.5 General Purpose I/Os
The AMC7836 device includes eight GPIO pins, each with an internal 48-kΩ pullup resistor to the IOVDD pin. The
GPIO[0:3] pins have dual functionality and can be programmed as either bidirectional digital I/O pins or interrupt
signals in the GPIO configuration register (address 0x12). The GPIO[4:7] pins are dedicated GPIOs. Table 4 lists
the dual function of the GPIO[0:3] pins.
Table 4. Dual Functionality GPIO Pins
PIN
DEFAULT PIN NAME
ALTERNATIVE PIN NAME
ALTERNATIVE
FUNCTIONALITY
7
GPIO0
ALARMIN
DAC clear control signal.
8
GPIO1
ALARMOUT
Global alarm output.
9
GPIO2
ADCTRIG
External ADC conversion trigger.
10
GPIO3
DAV
ADC data available indicator.
The GPIOs can receive an input or produce an output. When the GPIOn pin acts as an output, the status of the
pin is determined by the corresponding GPIO bit in the GPIO register (address 0x7A).
To use a GPIOn pin as an input, the corresponding GPIO bit in the GPIO register must be set to 1. When a
GPIOn pin acts as input, the digital value on the pin is acquired by reading the corresponding GPIO bit. After a
power-on reset (POR) or any forced reset, all GPIO bits are set to 1, and the GPIOn pins have a 48-kΩ input
impedance to the IOVDD pin (see Figure 60). The unused GPIO pins can be left floating.
IOVDD
48 kŸ
GPIOn
GPIOn Bit
(when writing)
ENABLE
GPIOn Bit
(when reading)
Figure 60. AMC7836 GPIO Pin
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7.4 Device Functional Modes
The sixteen DACs in the AMC7836 device are split into four groups, each with four DACs. The output range and
clamp voltage for each DAC group is set independently which enables the device to operate in one of the
following modes:
• All-positive DAC range mode
• All-negative DAC range mode
• Mixed DAC range mode
7.4.1 All-Positive DAC Range Mode
In the AMC7836 all-positive DAC range mode, each of the four DAC groups is set to a positive voltage output
range (0 to 5 V or 0 to 10 V).
Because the maximum DAC output for each group cannot exceed the common AVCC voltage for the device
(AVCC = AVCC_AB = AVCC_CD), a DAC group in the 0 to 10 V output range forces the AVCC voltage to a value
greater or equal to 10 V even if the remaining DAC groups are set in the 0 to 5 V range. If all DAC groups are
set in the 0 to 5 V range the AVCC voltage can be set to a value as low as 5 V.
The minimum DAC output for each group cannot be lower than the AVSS voltage but because the minimum DAC
output is 0 V in the all-positive DAC range mode, all of the AVSS pins (AVEE, AVSSB, AVSSC, and AVSSD) as well
as the device thermal pad can be tied to AGND thus simplifying the board design. Table 5 lists the typical
configurations for this mode.
Table 5. All-positive DAC Range Mode Typical Configuration
PIN
NOTES
TYPICAL CONNECTION
AVDD
5V
DVDD
DVDD must be equal to AVDD.
5V
IOVDD
IOVDD must be equal to or less than DVDD.
1.8 V to 5 V
AVCC_AB, AVCC_CD
The AVCC_AB and AVCC_CD pins must be tied
to the same potential (AVCC).
AVCC must be greater or equal than the
maximum possible output voltage for any of
the sixteen DACs.
AVCC ≥ 5 V
AVCC ≥ 10 V
AVEE
AGND
AVSSB, AVSSC, AVSSD
AGND
Thermal Pad
AGND
After power-on or a reset event the output range for each DAC group is set automatically by the voltage present
on the corresponding AVSS pin. In the all-positive DAC range mode all AVSS pins are connected to AGND and
consequently all four DAC groups will initialize by default to the 0 to 5 V range. The output for any of the DAC
groups can be modified to the 0 to 10 V range after initialization by setting the corresponding DAC range register
(address 0x1E to 0x1F) to 110b.
In addition to setting the default output range, the AVSS pins also set the clamp voltage for each DAC group.
Because the clamp voltage is only dependent on the voltage in the AVSS pin, changes to the DAC range
registers do not affect the clamp setting. With the AVSS pins connected to AGND, the clamp voltage for all
sixteen DACs is 0 V.
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7.4.2 All-Negative DAC Range Mode
In the AMC7836 all-negative DAC range mode, each of the four DAC groups is set to a negative voltage output
range (–5 to 0 V or –10 to 0 V).
Although the maximum DAC output does not exceed 0 V, the common AVCC voltage (AVCC = AVCC_AB =
AVCC_CD) must still satisfy a minimum voltage of 4.7 V to comply with the device operating conditions. In this
case a recommended approach is to tie the AVCC, AVDD, and DVDD supply pins to a common potential.
The minimum DAC output for each group cannot be lower than the voltage on the corresponding AVSS pins
(AVEE, AVSSB, AVSSC, and AVSSD). The AVSS pins are not required to be tied to the same potential and typically
the negative voltage at each AVSS pin is dictated by the desired operating DAC negative output range. One
exception is the AVEE pin which must be the lowest potential in the device. The thermal pad should be either tied
to the same potential as the AVEE pin or left disconnected. Table 6 lists the typical configurations for this mode.
Table 6. All-Negative DAC Range Mode Typical Configuration
PIN
NOTES
AVDD
TYPICAL CONNECTION
5V
DVDD
DVDD must be equal to AVDD.
5V
IOVDD
IOVDD must be equal to or less than DVDD.
1.8 V to 5 V
AVCC_AB, AVCC_CD
The AVCC_AB and AVCC_CD pins must be tied
to the same potential (AVCC).
5V
AVEE
AVEE must be the lowest potential in the
device.
AVEE must be less than or equal to the
minimum possible output voltage for DAC
group A.
AVEE ≤ –5 V
AVEE ≤ –10 V
AVSSB, AVSSC, AVSSD
AVSSn must be less than or equal to the
minimum possible output voltage for DAC
group n (n = B, C, D).
AVEE ≤ AVSSn ≤ –5 V
AVEE ≤ AVSSn ≤ –10 V
AVEE or,
Floating
Thermal Pad
After power-on or a reset event the output range for each DAC group is set automatically by the voltage present
in the corresponding AVSS pin. In the all-negative DAC range mode all AVSS pins should be connected to a
voltage lower than AVSSTH. If this condition is satisfied, all four DAC groups will initialize by default to the –10- to
0-V range. Because the negative clamp voltage is only dependent on the voltage in the AVSS pin, the default
–10- to 0-V output range presents no risk even when the AVSS voltage is greater than –10 V. In this case the
DAC group output should be modified to the –5 to 0 V range after initialization by setting the corresponding DAC
range register (address 0x1E to 0x1F) to 101b.
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7.4.3 Mixed DAC Range Mode
In the AMC7836 mixed DAC range mode, a combination of DAC groups is set to a negative voltage output range
(–5 to 0 V or –10 to 0 V) and a positive voltage output range (0 to 5 V or 0 to 10 V).
Because the maximum DAC output for each group cannot exceed the common AVCC voltage for the device
(AVCC = AVCC_AB = AVCC_CD), a DAC group in the 0 to 10 V output range forces the AVCC voltage to a value
greater or equal to 10 V. If all positive DAC groups are in the 0 to 5 V range the AVCC voltage can be set to a
value as low as 5 V.
The minimum DAC output for each group cannot be lower than the voltage on the corresponding AVSS pins
(AVEE, AVSSB, AVSSC and AVSSD). The AVSS pins are not required to be tied to the same potential and typically
the negative voltage at each AVSS pin is dictated by the desired operating DAC negative output range. One
exception is the AVEE pin which must be the lowest potential in the device. The implication of this requirement is
that if either DAC group B, C or D is set to a negative output range, DAC group A must also be set to a negative
range. The thermal pad should be either tied to the same potential as the AVEE pin or left disconnected. Table 7
lists the typical configurations for this mode.
Table 7. Mixed DAC Range Mode Typical Configuration
PIN
NOTES
TYPICAL CONNECTION
AVDD
5V
DVDD
DVDD must be equal to AVDD.
5V
IOVDD
IOVDD must be equal to or less than DVDD.
1.8 V to 5 V
AVCC_AB, AVCC_CD
The AVCC_AB and AVCC_CD pins must be tied to the
same potential (AVCC).
AVCC must be greater or equal to the maximum
possible output voltage for any of the positive
output range DACs.
AVCC ≥ 5 V
AVCC ≥ 10 V
AVEE
AVEE must be the lowest potential in the device.
AVEE must be less than or equal to the minimum
possible output voltage for DAC group A.
AVEE ≤ –5 V
AVEE ≤ –10 V
AVSSB, AVSSC, AVSSD
AVSSn must be less than or equal than the minimum Negative Range
possible output voltage for DAC group n (n = B, C,
D).
Positive Range
AVEE ≤ AVSSn ≤ –5 V
AVEE ≤ AVSSn ≤ –10 V
AGND
AVEE or,
Floating
Thermal Pad
After power-on or a reset event the output range for each DAC group is set automatically by the voltage present
in the corresponding AVSS pin. When the AVSS voltage of a DAC group is lower than the threshold value, AVSSTH,
the output for that DAC group is automatically configured to the –10 to 0 V range. Conversely, if the AVSS voltage
of the DAC group is higher than AVSSTH, the DAC-group output is automatically set to the 0 to 5 V range. The
output for any of the DAC groups can be modified after initialization by setting the corresponding DAC range
register (address 0x1E to 0x1F).
In addition to setting the default output range, the AVSS pins also set the clamp voltage for each DAC group.
Because the clamp voltage is only dependent on the voltage in the AVSS pin, changes to the DAC range
registers do not affect the clamp setting.
NOTE
Although not a recommended operating condition, the device allows a DAC group to
operate in a positive output range even if the clamp voltage is negative (AVSS connected
to a negative supply voltage).
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7.5 Programming
The AMC7836 device is controlled through a flexible four-wire serial interface that is compatible with SPI-type
interfaces used on many microcontrollers and DSP controllers. The interface provides read and write (R/W)
access to all registers of the AMC7836 device.
Each serial-interface access cycle is exactly (N + 2) bytes long, where N is the number of data bytes. Asserting
the CS pin low initiates a frame. The frame ends when the CS pin is deasserted high. In MSB-first mode, the first
bit transferred is the R/W bit. The next 15 bits are the register address (32768 addressable registers), and the
remaining bits are data. For all writes, data is committed in bytes as the eight data bit of a data field that is
clocked in on the rising edge of SCLK. If the write access is not an even multiple of 8 clocks, the trailing data bits
are not committed. On a read access, data is clocked out on the falling edge of the serial interface clock, SCLK,
on the SDO pin.
Figure 61 and Figure 62 show the access protocol used by the interface.
CS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
A8
A7
A6
A5
A4
A3
A2
A1
A0
D7
D6
D5
D4
D3
D2
D1
D0
SCLK
SDI
R/W A14 A13 A12 A11 A10 A9
SDO
Figure 61. Serial Interface Write Bus Cycle
CS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
A8
A7
A6
A5
A4
A3
A2
A1
A0
17
18
19
20
21
22
23
24
D7
D6
D5
D4
D3
D2
D1
D0
SCLK
SDI
R/W A14 A13 A12 A11 A10 A9
SDO
Figure 62. Serial Interface Read Bus Cycle
Streaming mode is supported for operations that require large amounts of data to be passed to or from the
AMC7836. In streaming mode multiple bytes of data can be written to or read from the AMC7836 without
specifically providing instructions for each byte. Streaming mode is implemented by continually holding the CS
pin active and continuing to shift new data in or old data out of the device.
The instruction phase includes the starting address. The AMC7836 device begins reading or writing data to this
address and continues as long as the CS pin is asserted and single byte writes have not been enabled in the
interface configuration 1 register (address 0x01). The AMC7836 device automatically increments or decrements
the address depending on the setting of the address ascension bit in the interface configuration 0 register
(address 0x00).
If the address is decrementing and address 0x0000 is reached, the next address used is 0x7FFF. If the address
is incrementing and address 0x7FFF is reached, the next address used is 0x0000. Care should be taken when
writing to address 0x0000 and 0x0001 as writing to these addresses may change the configuration of the serial
interface. Therefore address 0x0010 should be the first (ascending) or last (descending) address accessed in
streaming mode.
Figure 63 and Figure 64 show the access protocol used in streaming mode.
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Programming (continued)
CS
1
2
3
4
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
D7
Addr N+1 (ascending)
Addr N-1 (descending)
D6 D5 D4 D3 D2 D1
D0
SCLK
Address N
SDI
R/W A14 A13 A12
A2
A1
A0
D7
D6
D5
D4
D3
D2
D1
D0
SDO
Figure 63. Serial Interface Streaming Write Example
CS
1
2
3
4
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
D1
D0
SCLK
Addr N+1 (ascending)
Addr N-1 (descending)
Address N
SDI
R/W A14 A13 A12
A2
A1
A0
D7
SDO
D6
D5
D4
D3
D2
D1
D0
D7
D6
D5
D4
D3
D2
Figure 64. Serial Interface Streaming Read Example
44
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7.6 Register Maps
Table 8. Register Map
ADDRESS
TYPE
DEFAULT
0x00
R/W
30
Interface Configuration 0
REGISTER NAME
0x01
R/W
00
Interface Configuration 1
0x02
R/W
03
Device Configuration
0x03
R
08
Chip Type
0x04
R
36
Chip ID (Low Byte)
0x05
R
0C
Chip ID (High Byte)
0x06
R
00
Chip Version
0x07 – 0x0B
—
—
Reserved
0x0C
R
51
Manufacturer ID (Low Byte)
0x0D
R
04
Manufacturer ID (High Byte)
0x0E
—
—
Reserved
0x0F
R/W
00
Register Update
0x10
R/W
00
ADC Configuration
0x11
R/W
70
False Alarm Configuration
0x12
R/W
00
GPIO Configuration
0x13
R/W
00
ADC MUX Configuration 0
0x14
R/W
00
ADC MUX Configuration 1
0x15
R/W
00
ADC MUX Configuration 2
0x16
—
—
Reserved
0x17
—
—
Reserved
0x18
R/W
00
DAC Clear Enable 0
0x19
R/W
00
DAC Clear Enable 1
0x1A
R/W
00
DAC Clear Source 0
0x1B
R/W
00
DAC Clear Source 1
0x1C
R/W
00
ALARMOUT Source0
0x1D
R/W
00
ALARMOUT Source1
0x1E
R/W
00
DAC Range 0
0x1F
R/W
00
DAC Range 1
0x20
R
00
ADC0-Data (Low Byte)
0x21
R
00
ADC0-Data (High Byte)
0x22
R
00
ADC1-Data (Low Byte)
0x23
R
00
ADC1-Data (High Byte)
0x24
R
00
ADC2-Data (Low Byte)
0x25
R
00
ADC2-Data (High Byte)
0x26
R
00
ADC3-Data (Low Byte)
0x27
R
00
ADC3-Data (High Byte)
0x28
R
00
ADC4-Data (Low Byte)
0x29
R
00
ADC4-Data (High Byte)
0x2A
R
00
ADC5-Data (Low Byte)
0x2B
R
00
ADC5-Data (High Byte)
0x2C
R
00
ADC6-Data (Low Byte)
0x2D
R
00
ADC6-Data (High Byte)
0x2E
R
00
ADC7-Data (Low Byte)
0x2F
R
00
ADC7-Data (High Byte)
0x30
R
00
ADC8-Data (Low Byte)
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Table 8. Register Map (continued)
46
ADDRESS
TYPE
DEFAULT
0x31
R
00
REGISTER NAME
0x32
R
00
ADC9-Data (Low Byte)
0x33
R
00
ADC9-Data (High Byte)
0x34
R
00
ADC10-Data (Low Byte)
0x35
R
00
ADC10-Data (High Byte)
0x36
R
00
ADC11-Data (Low Byte)
0x37
R
00
ADC11-Data (High Byte)
0x38
R
00
ADC12-Data (Low Byte)
0x39
R
00
ADC12-Data (High Byte)
0x3A
R
00
ADC13-Data (Low Byte)
0x3B
R
00
ADC13-Data (High Byte)
0x3C
R
00
ADC14-Data (Low Byte)
0x3D
R
00
ADC14-Data (High Byte)
0x3E
R
00
ADC15-Data (Low Byte)
0x3F
R
00
ADC15-Data (High Byte)
0x40
R
00
ADC16-Data (Low Byte)
0x41
R
00
ADC16-Data (High Byte)
0x42
R
00
ADC17-Data (Low Byte)
0x43
R
00
ADC17-Data (High Byte)
0x44
R
00
ADC18-Data (Low Byte)
0x45
R
00
ADC18-Data (High Byte)
0x46
R
00
ADC19-Data (Low Byte)
0x47
R
00
ADC19-Data (High Byte)
0x48
R
00
ADC20-Data (Low Byte)
0x49
R
00
ADC20-Data (High Byte)
0x4A
R
00
Temperature Data (Low Byte)
0x4B
R
00
Temperature Data (High Byte)
0x4C - 0x4F
—
—
Reserved
0x50
R/W
00
DACA0-Data (Low Byte)
0x51
R/W
00
DACA0-Data (High Byte)
0x52
R/W
00
DACA1-Data (Low Byte)
0x53
R/W
00
DACA1-Data (High Byte)
0x54
R/W
00
DACA2-Data (Low Byte)
0x55
R/W
00
DACA2-Data (High Byte)
0x56
R/W
00
DACA3-Data (Low Byte)
0x57
R/W
00
DACA3-Data (High Byte)
0x58
R/W
00
DACB4-Data (Low Byte)
0x59
R/W
00
DACB4-Data (High Byte)
0x5A
R/W
00
DACB5-Data (Low Byte)
0x5B
R/W
00
DACB5-Data (High Byte)
0x5C
R/W
00
DACB6-Data (Low Byte)
0x5D
R/W
00
DACB6-Data (High Byte)
0x5E
R/W
00
DACB7-Data (Low Byte)
0x5F
R/W
00
DACB7-Data (High Byte)
0x60
R/W
00
DACC8-Data (Low Byte)
0x61
R/W
00
DACC8-Data (High Byte)
0x62
R/W
00
DACC9-Data (Low Byte)
ADC8-Data (High Byte)
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Table 8. Register Map (continued)
ADDRESS
TYPE
DEFAULT
0x63
R/W
00
REGISTER NAME
0x64
R/W
00
DACC10-Data (Low Byte)
0x65
R/W
00
DACC10-Data (High Byte)
0x66
R/W
00
DACC11-Data (Low Byte)
0x67
R/W
00
DACC11-Data (High Byte)
0x68
R/W
00
DACD12-Data (Low Byte)
0x69
R/W
00
DACD12-Data (High Byte)
0x6A
R/W
00
DACD13-Data (Low Byte)
0x6B
R/W
00
DACD13-Data (High Byte)
0x6C
R/W
00
DACD14-Data (Low Byte)
0x6D
R/W
00
DACD14-Data (High Byte)
0x6E
R/W
00
DACD15-Data (Low Byte)
0x6F
R/W
00
DACD15-Data (High Byte)
0x70
R
00
Alarm Status 0
0x71
R
00
Alarm Status 1
0x72
R
0C
General Status
0x73 - 0x79
—
—
Reserved
0x7A
R/W
FF
GPIO
0x7B - 0x7F
—
—
Reserved
0x80
R/W
FF
ADC16-Upper-Thresh (Low Byte)
0x81
R/W
0F
ADC16-Upper-Thresh (High Byte)
0x82
R/W
00
ADC16-Lower-Thresh (Low Byte)
0x83
R/W
00
ADC16-Lower-Thresh (High Byte)
0x84
R/W
FF
ADC17-Upper-Thresh (Low Byte)
0x85
R/W
0F
ADC17-Upper-Thresh (High Byte)
0x86
R/W
00
ADC17-Lower-Thresh (Low Byte)
0x87
R/W
00
ADC17-Lower-Thresh (High Byte)
0x88
R/W
FF
ADC18-Upper-Thresh (Low Byte)
0x89
R/W
0F
ADC18-Upper-Thresh (High Byte)
0x8A
R/W
00
ADC18-Lower-Thresh (Low Byte)
0x8B
R/W
00
ADC18-Lower-Thresh (High Byte)
0x8C
R/W
FF
ADC19-Upper-Thresh (Low Byte)
0x8D
R/W
0F
ADC19-Upper-Thresh (High Byte)
0x8E
R/W
00
ADC19-Lower-Thresh (Low Byte)
0x8F
R/W
00
ADC19-Lower-Thresh (High Byte)
0x90
R/W
FF
ADC20-Upper-Thresh (Low Byte)
0x91
R/W
0F
ADC20-Upper-Thresh (High Byte)
0x92
R/W
00
ADC20-Lower-Thresh (Low Byte)
0x93
R/W
00
ADC20-Lower-Thresh (High Byte)
0x94
R/W
FF
LT-Upper-Thresh (Low Byte)
0x95
R/W
07
LT-Upper-Thresh (High Byte)
0x96
R/W
00
LT-Lower-Thresh (Low Byte)
0x97
R/W
08
LT-Lower-Thresh (High Byte)
0x98 - 0x9F
—
—
Reserved
0xA0
R/W
08
ADC16-Hysteresis
0xA1
R/W
08
ADC17-Hysteresis
0xA2
R/W
08
ADC18-Hysteresis
DACC9-Data (High Byte)
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Table 8. Register Map (continued)
48
ADDRESS
TYPE
DEFAULT
REGISTER NAME
0xA3
R/W
08
ADC19-Hysteresis
0xA4
R/W
08
ADC20-Hysteresis
0xA5
R/W
08
LT-Hysteresis
0xA6 - 0xAF
—
—
Reserved
0xB0
R/W
00
DAC Clear 0
0xB1
R/W
00
DAC Clear 1
0xB2
R/W
00
Power-Down 0
0xB3
R/W
00
Power-Down 1
0xB4
R/W
00
Power-Down 2
0xB5 - 0xBF
—
—
Reserved
0xC0
R/W
00
ADC Trigger
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7.6.1 Interface Configuration: Address 0x00 – 0x02
7.6.1.1 Interface Configuration 0 Register (address = 0x00) [reset = 0x30]
Figure 65. Interface Configuration 0 (Interface Config 0) Register (R/W)
7
SOFT-RESET
6
Reserved
R/W-0
R/W-0
5
ADDRASCEND
R/W-1
4
Reserved
3
2
1
0
Reserved
R/W-1
R/W-All zeros
Table 9. Interface Config 0 Register Field Descriptions (R/W)
Bit
7
Field
Type
Reset
Description
SOFT-RESET
R/W
0
Soft reset (self-clearing)
0: no action
1: reset – resets everything except address 0x00, 0x01
6
Reserved
R/W
0
Reserved for factory use
5
ADDR-ASCEND
R/W
1
Address Ascend
0: Descend – decrements address while streaming
(address wrap from 0x0000 to 0x7FFF)
1: Ascend – increments address while streaming (address
wrap from 0x7FFF to 0x0000)
4
Reserved
R/W
1
Reserved for factory use
3-0
Reserved
R/W
All zeros
Reserved for factory use
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7.6.1.2 Interface Configuration 1 Register (address = 0x01) [reset = 0x00]
Figure 66. Interface Configuration 1 (Interface Config 1) Register (R/W)
7
SINGLE-INSTR
R/W-0
6
Reserved
R/W-0
5
READBACK
R/W-0
4
3
2
Reserved
R/W-All zeros
1
0
Table 10. Interface Config 1 Register Field Descriptions
Bit
7
Field
Type
Reset
Description
SINGLE-INSTR
R/W
0
Single instruction enable
0: streaming mode (default)
1: single instruction
6
Reserved
R/W
0
Reserved for factory use
5
READBACK
R/W
0
Read back
0: DAC read back from active registers (default)
1: DAC read back from buffer registers
4-0
Reserved
R/W
All zeros
Reserved for factory use
7.6.1.3 Device Configuration Register (address = 0x02) [reset = 0x03]
Figure 67. Device Configuration (Device Config) Register (R/W)
7
6
5
4
3
2
1
Reserved
R/W-All Zeros
0
POWER-MODE
R/W-11
Table 11. Device Config Register Field Descriptions
Bit
Field
Type
Reset
Description
7-2
Reserved
R/W
All zeros
Reserved for factory use
1-0
POWER-MODE
R/W
11
Mode:
00: Normal operation – full power and full performance
11: Power Down – lowest power, non-operational except
SPI
One time overwrite of the power-down registers (0xB2 and
0xB3)
7.6.2 Device Identification: Address 0x03 – 0x0D
7.6.2.1 Chip Type Register (address = 0x03) [reset = 0x08]
Figure 68. Chip Type Register (R)
7
6
5
4
3
Reserved
R-0x0
2
1
0
CHIP-TYPE
R-0x8
Table 12. Chip Type Register Field Descriptions
50
Bit
Field
Type
Reset
Description
7-4
Reserved
R
0x0
Reserved for factory use
3-0
CHIP-TYPE
R
0x8
Identifies the device as a precision analog monitor and control
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7.6.2.2 Chip ID Low Byte Register (address = 0x04) [reset = 0x36]
Figure 69. Chip ID Low Byte Register (R)
7
6
5
4
3
2
1
0
1
0
1
0
CHIPID-LOW
R-0x36
Table 13. Chip ID Low Byte Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
CHIPID-LOW
R
0x36
Chip ID. Low byte
7.6.2.3 Chip ID High Byte Register (address = 0x05) [reset = 0x0C]
Figure 70. Chip ID High Byte Register (R)
7
6
5
4
3
2
CHIPID-HIGH
R-0x0C
Table 14. Chip ID High Byte Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
CHIPID-HIGH
R
0x0C
Chip ID. High byte
7.6.2.4 Version ID Register (address = 0x06) [reset = 0x00]
Figure 71. Version ID Register (R)
7
6
5
4
3
2
VERSIONID
R-0x00
Table 15. Version ID Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
VERSIONID
R
0x00
AMC7836 version ID. Subject to change
7.6.2.5 Manufacturer ID Low Byte Register (address = 0x0C) [reset = 0x51]
Figure 72. Manufacturer ID Low Byte Register (R)
7
6
5
4
3
VENDORID-LOW
R-0x51
2
1
0
Table 16. Manufacturer ID Low Byte Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
VENDORID-LOW
R
0x51
Manufacturer ID. Low byte
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7.6.2.6 Manufacturer ID High Byte Register (address = 0x0D) [reset = 0x04]
Figure 73. Manufacturer ID High Byte Register
7
6
5
4
3
VENDORID-HIGH
R-0x04
2
1
0
1
0
UPDATE
R/W-0
Table 17. Manufacturer ID High Byte Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
VENDORID-HIGH
R
0x04
Manufacturer ID. High byte
7.6.3 Register Update (Buffered Registers): Address 0x0F
7.6.3.1 Register Update Register (address = 0x0F) [reset = 0x00]
Figure 74. Register Update Register (Self Clearing) [R/W]
7
6
Reserved
R/W-All Zeros
5
4
ADC-UPDATE
R/W-0
3
2
Reserved
R/W-All Zeros
Table 18. Register Update Register Field Descriptions
Bit
Field
Type
Reset
Description
7-5
Reserved
R/W
All zeros
Reserved for factory use
ADC-UPDATE
R/W
0
When set transfers the latest ADC and temperature conversion
data to the ADC and Temperature Data registers. This function
is needed when operating the ADC in auto-cycle mode
Reserved
R/W
All zeros
Reserved for factory use
DAC-UPDATE
R/W
0
DAC update (self clearing)
4
3-1
0
0: disabled
1: enabled – transfers data from buffers to active registers
(DAC registers only)
52
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7.6.4 General Device Configuration: Address 0x10 through 0x17
7.6.4.1 ADC Configuration Register (address = 0x10) [reset = 0x00]
Figure 75. ADC Configuration Register (R/W)
7
CMODE
6
5
CONV-RATE[1:0]
R/W-0
R/W-00
4
ADC-REFBUFF
R/W-0
3
2
1
0
Reserved
R/W-All zeros
Table 19. ADC Configuration Register Field Descriptions
Bit
7
Field
Type
Reset
Description
CMODE
R/W
0
ADC Conversion Mode Bit. This bit selects the ADC conversion
mode.
0: Direct mode. The analog inputs specified in the ADC
channel registers are converted sequentially one time.
When one set of conversions is complete, the ADC is idle
and waits for a new trigger.
1: Auto mode. The analog inputs specified in the AMC
channel registers are converted sequentially and
repeatedly. When one set of conversions is complete, the
ADC multiplexer returns to the first channel and repeats the
process. The ADC-UPDATE bit in register 0x0F must be
used to initiate the transfer of the latest conversion data to
the ADC Data registers.
6-5
CONV-RATE[1:0]
R/W
00
ADC Conversion rate. See Table 20 to configure this setting.
4
ADC-REF-BUFF
R/W
0
ADC Reference Buffer bit. This bit must be set to 1 after device
power-up to enable the internal reference buffer driving the
ADC.
0: ADC reference buffer is disabled.
1: ADC reference buffer is enabled.
3-0
Reserved
R/W
All zeros
Reserved for factory use
Table 20. CONV-RATE[1:0] Bit Configuration
CONV-RATE[1:0]
Unipolar Channel Sample Time (µs)
Bipolar Channel Sample
Time (µs)
00
11.5
34.5
01
23
34.5
10
34.5
34.5
11
69
69
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7.6.4.2 False Alarm Configuration Register (address = 0x11) [reset = 0x70]
Figure 76. False Alarm Configuration Register (R/W)
7
6
CH-FALR-CT[2:0]
R/W-011
5
4
3
TEMP-FALR-CT[1:0]
R/W–10
2
1
Reserved
R/W-All zeros
0
Table 21. False Alarm Configuration Register Field Descriptions
Bit
Field
Type
Reset
Description
7-5
CH-FALR-CT[2:0]
R/W
011
False alarm protection for ADC channels. See Table 22 to
configure this bit.
4-3
TEMP-FALR-CT[1:0]
R/W
10
False alarm protection for temperature sensor. See Table 23 to
configure this bit.
2-0
Reserved
R/W
All zeros
Reserved for factory use
Table 22. CH-FALR-CT Bit Configuration
CH-FALR-CT
N Consecutive Samples Before
Alarm is Set
000
1
001
4
010
8
011
16
100
32
101
64
110
128
111
256
Table 23. TEMP-FALR-CT Bit Configuration
54
TEMP-FALR-CT
N Consecutive Samples Before
Alarm is Set
00
1
01
2
10
4
11
8
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7.6.4.3 GPIO Configuration Register (address = 0x12) [reset = 0x00]
Figure 77. GPIO Configuration Register (R/W)
7
6
Reserved
5
R/W-All zeros
4
Reserved
3
EN-DAV
2
EN-ADCTRIG
R/W-0
R/W-0
R/W-0
1
ENALARMOUT
R/W-0
0
EN-ALARMIN
R/W-0
Table 24. GPIO Configuration Register Field Descriptions
Bit
Field
Type
Reset
Description
7-5
Reserved
R/W
All zeros
Reserved for factory use
4
Reserved
R/W
0
Reserved for factory use
3
EN-DAV
R/W
0
DAV pin enable
0: GPIO3 operation (default)
1: DAV operation
2
EN-ADCTRIG
R/W
0
ADCTRIG pin enable
0: GPIO2 operation (default)
1: ADCTRIG operation
1
EN-ALARMOUT
R/W
0
ALARMOUT pin enable
0: GPIO1 operation (default)
1: ALARMOUT operation
0
EN-ALARMIN
R/W
0
ALARMIN pin enable
0: GPIO0 operation (default)
1: ALARMIN operation
7.6.4.4 ADC MUX Configuration 0 Register (address = 0x13) [reset = 0x00]
Figure 78. ADC MUX Configuration 0 Register (R/W)
7
CH7
R/W-0
6
CH6
R/W-0
5
CH5
R/W-0
4
CH4
R/W-0
3
CH3
R/W-0
2
CH2
R/W-0
1
CH1
R/W-0
0
CH0
R/W-0
Table 25. ADC MUX Configuration 0 Register Field Descriptions
Bit
Field
Type
Reset
Description
7
CH7
R/W
0
6
CH6
R/W
0
When set to 1 the corresponding analog input channel ADC_n is
accessed during an ADC conversion cycle.
5
CH5
R/W
0
4
CH4
R/W
0
3
CH3
R/W
0
2
CH2
R/W
0
1
CH1
R/W
0
0
CH0
R/W
0
When cleared to 0 the corresponding input channel ADC_n is
ignored during an ADC conversion cycle.
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7.6.4.5 ADC MUX Configuration 1 Register (address = 0x14) [reset = 0x00]
Figure 79. ADC MUX Configuration 1 Register (R/W)
7
CH15
R/W-0
6
CH14
R/W-0
5
CH13
R/W-0
4
CH12
R/W-0
3
CH11
R/W-0
2
CH10
R/W-0
1
CH9
R/W-0
0
CH8
R/W-0
Table 26. ADC MUX Configuration 1 Register Field Descriptions
Bit
Field
Type
Reset
Description
7
CH15
R/W
0
6
CH14
R/W
0
When set to 1 the corresponding analog input channel ADC_n is
accessed during an ADC conversion cycle.
5
CH13
R/W
0
4
CH12
R/W
0
3
CH11
R/W
0
2
CH10
R/W
0
1
CH9
R/W
0
0
CH8
R/W
0
When cleared to 0 the corresponding input channel ADC_n is
ignored during an ADC conversion cycle.
7.6.4.6 ADC MUX Configuration 2 Register (address = 0x15) [reset = 0x00]
Figure 80. ADC MUX Configuration 2 Register (R/W)
7
6
Reserved
R/W-All Zeros
5
TEMP-CH
R/W-0
4
CH20
R/W-0
3
CH19
R/W-0
2
CH18
R/W-0
1
CH17
R/W-0
0
CH16
R/W-0
Table 27. ADC MUX Configuration 2 Register Field Descriptions
Bit
Field
Type
Reset
Description
7-6
Reserved
R/W
All Zeros
Reserved for factory use
5
TEMP-CH
R/W
0
When set to 1 the local temperature sensor is enabled for ADC
conversion.
4
CH20
R/W
0
3
CH19
R/W
0
2
CH18
R/W
0
1
CH17
R/W
0
0
CH16
R/W
0
When cleared to 0 the local temperature sensor is ignored.
56
When set to 1 the corresponding analog input channel ADC_n is
accessed during an ADC conversion cycle.
When cleared to 0 the corresponding input channel ADC_n is
ignored during an ADC conversion cycle.
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7.6.4.7 DAC Clear Enable 0 Register (address = 0x18) [reset = 0x00]
Figure 81. DAC Clear Enable 0 Register (R/W)
7
CLREN-B7
R/W-0
6
CLREN-B6
R/W-0
5
CLREN-B5
R/W-0
4
CLREN-B4
R/W-0
3
CLREN-A3
R/W-0
2
CLREN-A2
R/W-0
1
CLREN-A1
R/W-0
0
CLREN-A0
R/W-0
Table 28. DAC Clear Enable 0 Register Field Descriptions
Bit
Field
Type
Reset
Description
7
CLREN-B7
R/W
0
6
CLREN-B6
R/W
0
5
CLREN-B5
R/W
0
This register determines which DACs go into clear state when a
clear event is detected as configured in the DAC-CLEARSOURCE registers.
4
CLREN-B4
R/W
0
3
CLREN-A3
R/W
0
2
CLREN-A2
R/W
0
1
CLREN-A1
R/W
0
0
CLREN-A0
R/W
0
If CLRENn = 1, DAC_n is forced into a clear state with a
clear event.
If CLRENn = 0, a clear event does not affect the state of
DAC_n.
7.6.4.8 DAC Clear Enable 1 Register (address = 0x19) [reset = 0x00]
Figure 82. DAC Clear Enable 1 Register (R/W)
7
CLREN-D15
R/W-0
6
CLREN-D14
R/W-0
5
CLREN-D13
R/W-0
4
CLREN-D12
R/W-0
3
CLREN-C11
R/W-0
2
CLREN-C10
R/W-0
1
CLREN-C9
R/W-0
0
CLREN-C8
R/W-0
Table 29. DAC Clear Enable 1 Register Field Descriptions
Bit
Field
Type
Reset
Description
7
CLREN-D15
R/W
0
6
CLREN-D14
R/W
0
5
CLREN-D13
R/W
0
This register determines which DACs go into clear state when a
clear event is detected as configured in the DAC-CLEARSOURCE registers.
4
CLREN-D12
R/W
0
3
CLREN-C11
R/W
0
2
CLREN-C10
R/W
0
1
CLREN-C9
R/W
0
0
CLREN-C8
R/W
0
If CLRENn = 1, DAC_n is forced into a clear state with a
clear event.
If CLRENn = 0, a clear event does not affect the state of
DAC_n.
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7.6.5 DAC Clear and ALARMOUT Source Select: Address 0x1A through 0x1D
7.6.5.1 DAC Clear Source 0 Register (address = 0x1A) [reset = 0x00]
Figure 83. DAC Clear Source 0 Register (R/W)
7
6
Reserved
5
R/W-All zeros
4
ADC20-ALRCLR
R/W-0
3
ADC19-ALRCLR
R/W-0
2
ADC18-ALRCLR
R/W-0
1
ADC17-ALRCLR
R/W-0
0
ADC16-ALRCLR
R/W-0
Table 30. DAC Clear Source 0 Register Field Descriptions
Bit
Field
Type
Reset
Description
7-5
Reserved
R/W
All zeros
Reserved for factory use
4
ADC20-ALR-CLR
R/W
0
3
ADC19-ALR-CLR
R/W
0
2
ADC18-ALR-CLR
R/W
0
This register selects which alarm forces DACs into a clear state,
regardless of which DAC operation mode is active, auto or
manual. In order for DAC_n to go into clear mode, it must be
enabled in the DAC Clear Enable registers.
1
ADC17-ALR-CLR
R/W
0
0
ADC16-ALR-CLR
R/W
0
7.6.5.2 DAC Clear Source 1 Register (address = 0x1B) [reset = 0x00]
Figure 84. DAC Clear Source 1 Register (R/W)
7
6
5
4
3
ALARMIN-ALR
R/W-0
Reserved
R/W-All zeros
2
THERM-ALR
R/W-0
1
LT-HIGH-ALR
R/W-0
0
LT-LOW-ALR
R/W-0
Table 31. DAC Clear Source 1 Register Field Descriptions
Bit
Field
Type
Reset
Description
7-4
Reserved
R/W
All zeros
Reserved for factory use
3
ALARMIN-ALR
R/W
0
2
THERM-ALR
R/W
0
1
LT-HIGH-ALR
R/W
0
This register selects which alarm forces DACs into a clear state,
regardless of which DAC operation mode is active, auto or
manual. In order for DAC_n to go into clear mode, it must be
enabled in the DAC Clear Enable registers.
0
LT-LOW-ALR
R/W
0
7.6.5.3 ALARMOUT Source 0 Register (address = 0x1c) [reset = 0x00]
Figure 85. ALARMOUT Source 0 Register (R/W)
7
6
Reserved
R/W-All zeros
5
4
ADC20-ALROUT
R/W-0
3
ADC19-ALROUT
R/W-0
2
ADC18-ALROUT
R/W-0
1
ADC17-ALROUT
R/W-0
0
ADC16-ALROUT
R/W-0
Table 32. ALARMOUT Source 0 Register Field Descriptions
58
Bit
Field
Type
Reset
Description
7-5
Reserved
R/W
All zeros
Reserved for factory use
4
ADC20-ALR-OUT
R/W
0
3
ADC19-ALR-OUT
R/W
0
2
ADC18-ALR-OUT
R/W
0
This register selects which alarms can activate the ALARMOUT
pin. The ALARMOUT must be enabled for this function to take
effect.
1
ADC17-ALR-OUT
R/W
0
0
ADC16-ALR-OUT
R/W
0
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7.6.5.4 ALARMOUT Source 1 Register (address = 0x1D) [reset = 0x00]
Figure 86. ALARMOUT Source 1 Register (R/W)
7
6
Reserved
5
4
ALARMLATCH-DIS
R/W-0
R/W-All zeros
3
ALRIN-ALROUT
R/W-0
2
THERM-ALROUT
R/W-0
1
LT-HIGH-ALROUT
R/W-0
0
LT-LOW-ALROUT
R/W-0
Table 33. ALARMOUT Source 1 Register Field Descriptions
Bit
Field
Type
Reset
Description
7-5
Reserved
R/W
All zeros
Reserved for factory use
ALARM-LATCH-DIS
R/W
0
Alarm latch disable bit.
4
When cleared to 0 the alarm bits are latched. When an alarm
occurs, the corresponding alarm bit is set to “1”. The alarm bit
remains until the error condition subsides and the alarm register
is read. Before reading, the alarm bit is not cleared even if the
alarm condition disappears. When set to 1 the alarm bits are not
latched. When the alarm condition subsides, the alarm bits are
cleared regardless of whether the alarm bits have been read or
not.
3
ALRIN-ALR-OUT
R/W
0
2
THERM-ALR-OUT
R/W
0
1
LT-HIGH-ALR-OUT
R/W
0
0
LT-LOW-ALR-OUT
R/W
0
This register selects which alarms can activate the ALARMOUT
pin. The ALARMOUT must be enabled for this function to take
effect.
7.6.6 DAC Range: Address 0x1E
7.6.6.1 DAC Range Register (address = 0x1E) [reset = 0x00]
Figure 87. DAC Range Register (R/W)
7
Reserved
R/W-0
6
5
DAC-RANGEB[2:0]
R/W-All zeros
4
3
Reserved
R/W-0
2
1
DAC-RANGEA[2:0]
R/W-All zeros
0
Table 34. DAC Range Register Field Descriptions
Bit
Field
Type
Reset
Description
Reserved
R/W
0
Reserved for factory use
DAC-RANGEB[2:0]
R/W
All zeros
DAC group B output voltage selection. Overrides output range
set by the auto-range detection circuit. See Table 35 to
configure this setting.
3
Reserved
R/W
0
Reserved for factory use
2
DAC-RANGEA[2:0]
R/W
All zeros
DAC group A output voltage selection. Overrides output range
set by the auto-range detection circuit. See Table 35 to
configure this setting.
7
6-4
Table 35. DAC-RANGEx Bit Configuration
DAC-RANGEx[2:0]
DAC Group x Output Voltage Range
0xx
Range set by auto-range detection circuit
100
–10 to 0 V
101
-5 to 0 V
110
0 to 10 V
111
0 to 5 V
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7.6.6.2 DAC Range 1 Register (address = 0x1F) [reset = 0x00]
Figure 88. DAC Range 1 Register (R/W)
7
Reserved
R/W-0
6
5
DAC-RANGED[2:0]
R/W-All zeros
4
3
Reserved
R/W-0
2
1
DAC-RANGEC[2:0]
R/W-All zeros
0
Table 36. DAC Range 1 Register Field Descriptions
Bit
Field
Type
Reset
Description
Reserved
R/W
0
Reserved for factory use
DAC-RANGED[2:0]
R/W
All zeros
DAC group D output voltage selection. Overrides output range
set by the auto-range detection circuit. See Table 35 to
configure this setting.
3
Reserved
R/W
0
Reserved for factory use
2
DAC-RANGEC[2:0]
R/W
All zeros
DAC group C output voltage selection. Overrides output range
set by the auto-range detection circuit. See Table 35 to
configure this setting.
7
6-4
7.6.7 ADC and Temperature Data: Address 0x20 through 0x4B
7.6.7.1 ADCn-Data (Low Byte) Register (address = 0x20 through 0x49) [reset = 0x00]
Figure 89. ADCn-Data (Low Byte) Register (R)
7
6
5
4
3
ADCn-DATA(7:0)
R-All zeros
2
1
0
Table 37. ADCn-Data (Low Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
ADCn-DATA(7:0)
R
All zeros
Stores the 12-bit ADC_n conversion results in straight binary
format for both types of inputs channels (unipolar and bipolar)
7.6.7.2 ADCn-Data (High Byte) Register (address = 0x20 through 0x49) [reset = 0x00]
Figure 90. ADCn-Data (High Byte) Register (R)
7
6
5
4
3
Reserved
R-All zeros
2
1
ADCn-DATA (11:8)
R-All zeros
0
Table 38. ADCn-Data (High Byte) Register Field Descriptions
60
Bit
Field
Type
Reset
Description
7-4
Reserved
R
All zeros
Reserved for factory use
3-0
ADCn-DATA (11:8)
R
All zeros
Stores the 12-bit ADC_n conversion results in straight binary
format for both types of inputs channels (unipolar and bipolar).
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7.6.7.3 Temperature Data (Low Byte) Register (address = 0x4A) [reset = 0x00]
Figure 91. Temperature Data (Low Byte) Register (R)
7
6
5
4
3
TEMP-DATA(7:0)
R-All zeros
2
1
0
Table 39. Temperature Data (Low Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
TEMP-DATA(7:0)
R
All zeros
Stores the temperature sensor reading in twos complement
format.
7.6.7.4 Temperature Data (High Byte) Register (address = 0x4B) [reset = 0x00]
Figure 92. Temperature Data (High Byte) Register (R)
7
6
5
4
3
Reserved
R-All zeros
2
1
TEMP-DATA(11:8)
R-All zeros
0
Table 40. Temperature Data (High Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-4
Reserved
R
All zeros
Reserved for factory use.
3-0
TEMP-DATA(11:8)
R
All zeros
Stores the temperature sensor reading in twos complement
format.
7.6.8 DAC Data: Address 0x50 through 0x6F
7.6.8.1 DACn-Data (Low Byte) Register (address = 0x50 through 0x6F) [reset = 0x00]
Figure 93. DACn-Data (Low Byte) Register (R/W)
7
6
5
4
3
DACn-DATA (7:0)
R/W-All zeros
2
1
0
Table 41. DACn-Data (Low Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
DACn-DATA (7:0)
R/W
All zeros
Stores the 12-bit data to be loaded to the DAC_n latches in
straight binary format. The straight binary format is used for all
DAC ranges.
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7.6.8.2 DACn Data (High Byte) Register (address = 0x50 through 0x6F) [reset = 0x00]
Figure 94. DACn Data (High Byte) Register (R/W)
7
6
5
4
3
Reserved
R/W-All zeros
2
1
DACn-DATA (11:8)
R/W-All zeros
0
Table 42. DACn Data (High Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-4
Reserved
R/W
All zeros
Reserved for factory use
3-0
DACn-DATA (11:8)
R/W
All zeros
Stores the 12-bit data to be loaded to the DAC_n latches in
straight binary format. The straight binary format is used for all
DAC ranges.
7.6.9 Status Registers: Address 0x70 through 0x72
The AMC7836 device continuously monitors all general purpose analog inputs and local temperature sensor
during normal operation. When any input is out of the specified range N consecutive times, the corresponding
alarm bit is set (1). If the input returns to the normal range before N consecutive times, the corresponding alarm
bit remains clear (0). This configuration avoids any false alarms. When an alarm status occurs, the
corresponding alarm bit is set (1). When the corresponding bit in the ALARMOUT Source Registers is cleared
(0), the ALARMOUT pin is latched.
Whenever an alarm status bit is set, it remains set until the event that caused it is resolved and its status register
is read. Reading the Alarm Status Registers clears the alarm status bits. The alarm bit can only be cleared by
reading its Alarm Status register after the event is resolved, or by hardware reset, software reset, or power-on
reset. All alarm status bits are cleared when reading the Alarm Status registers, and all these bits are reasserted
if the out-of-limit condition still exists after the next conversion cycle, unless otherwise noted.
62
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7.6.9.1 Alarm Status 0 Register (address = 0x70) [reset = 0x00]
Figure 95. Alarm Status 0 Register (R)
7
6
Reserved
R-All zeros
5
4
ADC20-ALR
R-0
3
ADC19-ALR
R-0
2
ADC18-ALR
R-0
1
ADC17-ALR
R-0
0
ADC16-ALR
R-0
Table 43. Alarm Status 0 Register Field Descriptions
Bit
Field
Type
Reset
Description
7-5
Reserved
R
All zeros
Reserved for factory use
ADC20-ALR
R
0
ADC20-ALR = 1 when ADC20 is out of the range defined by the
corresponding threshold registers.
4
ADC20-ALR = 0 when the analog input is not out of the
specified range.
3
ADC19-ALR
R
0
ADC19-ALR = 1 when ADC19 is out of the range defined by the
corresponding threshold registers.
ADC19-ALR = 0 when the analog input is not out of the
specified range.
2
ADC18-ALR
R
0
ADC18-ALR = 1 when ADC18 is out of the range defined by the
corresponding threshold registers.
ADC18-ALR = 0 when the analog input is not out of the
specified range.
1
ADC17-ALR
R
0
ADC17-ALR = 1 when ADC17 is out of the range defined by the
corresponding threshold registers.
ADC17-ALR = 0 when the analog input is not out of the
specified range.
0
ADC16-ALR
R
0
ADC16-ALR = 1 when ADC16 is out of the range defined by the
corresponding threshold registers.
ADC16-ALR = 0 when the analog input is not out of the
specified range.
7.6.9.2 Alarm Status 1 Register (address = 0x71) [reset = 0x00]
Figure 96. Alarm Status 1 Register (R)
7
6
5
4
3
ALARMIN-ALR
R-0
Reserved
R-All zeros
2
THERM-ALR
R-0
1
LT-HIGH-ALR
R-0
0
LT-LOW-ALR
R-0
Table 44. Alarm Status 1 Register Field Descriptions
Bit
Field
Type
Reset
Description
7-4
Reserved
R
All zeros
Reserved for factory use
3
ALARMIN-ALR
R
0
The ALARMIN-ALR is set to 1 if the ALARMIN pin is enabled
and set high.
2
THERM-ALR
R
0
Thermal alarm flag. When the die temperature is equal to or
greater than +150°C, the bit is set (1) and the THERM-ALR flag
activates. The on-chip temperature sensor (LT) monitors the die
temperature. If LT is disabled, the THERM-ALR bit is always 0.
The hysteresis of this alarm is 8°C.
1
LT-HIGH-ALR
R
0
LT-HIGH-ALR = 1 when the temperature sensor is out of the
range defined by the upper threshold.
0
LT-LOW-ALR
R
0
LT-LOW-ALR = 1 when the temperature sensor is out of the
range defined by the lower threshold.
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7.6.9.3 General Status Register (address = 0x72) [reset = 0x0C]
Figure 97. General Status Register (R)
7
AVSSD
—
6
AVSSC
—
5
AVSSB
—
4
AVSSA
—
3
ADC_IDLE
R-1
2
Reserved
R-1
1
GALR
R-0
0
DAVF
R-0
Table 45. General Status Register Field Descriptions
Bit
Reset
Description
7
Field
AVSSD
Type
—
This bit is the auto-range detection output for DAC group D. This
bit is set to 1 when AVSSD < AVSSTH (–10- to 0-V output range),
and 0 when AVSSD > AVSSTH (0- to 5-V output range).
6
AVSSC
—
This bit is the auto-range detection output for DAC group C. This
bit is set to 1 when AVSSC < AVSSTH (–10- to 0-V output range),
and 0 when AVSSC > AVSSTH (0- to 5-V output range).
5
AVSSB
—
This bit is the auto-range detection output for DAC group B. This
bit is set to 1 when AVSSB < AVSSTH (–10- to 0-V output range),
and 0 when AVSSB > AVSSTH (0- to 5-V output range).
4
AVSSA
—
This bit is the auto-range detection output for DAC group A. This
bit is set to 1 when AVEE < AVSSTH (–10- to 0-V output range),
and 0 when AVEE > AVSSTH (0- to 5-V output range).
3
ADC_IDLE
1
ADC Idle indicator.
R
Auto mode: 1 by default; goes to 0 once the ADC is
triggered and is running. Remains 0 until ADC is stopped,
then ADC_IDLE returns to 1.
Direct mode: 1 by default; goes to 0 once the ADC is
triggered and direct conversions are running and returns to
1 when direct mode conversions are completed.
2
Reserved
R
1
Reserved for factory use
1
GALR
R
0
Global alarm bit.
This bit is the OR function or all individual alarm bits of the
status register. This bit is set to 1 when any alarm condition
occurs and remains set until the status register is read. This bit
is cleared after reading the Status Register.
0
DAVF
R
0
ADC Data available flag bit. Direct mode only. Always cleared in
Auto mode.
0: ADC conversion is in progress or ADC is in Auto mode
1: ADC conversions are complete and new data is available
64
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7.6.10 GPIO: Address 0x7A
7.6.10.1 GPIO Register (address = 0x7A) [reset = 0xFF]
Figure 98. GPIO Register (R/W)
7
GPIO-7
R/W-1
6
GPIO-6
R/W-1
5
GPIO-5
R/W-1
4
GPIO-4
R/W-1
3
GPIO-3
R/W-1
2
GPIO-2
R/W-1
1
GPIO-1
R/W-1
0
GPIO-0
R/W-1
Table 46. GPIO Register Field Descriptions
Bit
Field
Type
Reset
Description
7
GPIO-7
R/W
1
6
GPIO-6
R/W
1
5
GPIO-5
R/W
1
For write operation the GPIO pin operates as an output. Writing
a 1 to the GPIO-n bit sets the GPIO-N pin to high impedance.
Writing a 0 sets the GPIO-n pin to logic low.
4
GPIO-4
R/W
1
For read operations the GPIO pin operates as an input. Read
the GPIO-n bit to receive the status of the GPIO-n pin.
3
GPIO-3
R/W
1
The GPIO-n pin has 48-kΩ input impedance to IOVDD.
2
GPIO-2
R/W
1
1
GPIO-1
R/W
1
0
GPIO-0
R/W
1
7.6.11 Out-Of-Range ADC Thresholds: Address 0x80 through 0x93
The unipolar analog inputs (LV_ADC16 to LV_ADC20) and the local temperature sensor implement an out-ofrange alarm function. The Upper-Thresh and Lower-Thresh registers define the upper bound and lower bounds
for these inputs. This window determines whether the analog input or temperature is out-of-range. When the
input is outside the window, the corresponding CH-ALR-n bit in the Status Register is set to 1. For normal
operation, the value of the upper threshold must be greater than the value of lower threshold; otherwise, an
alarm is always indicated. The analog input threshold values are specified in straight binary format while the local
temperature ones are specified in two’s complement format.
7.6.11.1 ADCn-Upper-Thresh (Low Byte) Register (address = 0x80 through 0x93) [reset = 0xFF]
Figure 99. ADCn-Upper-Thresh (Low Byte) Register (R/W)
7
6
5
4
3
2
1
0
THRUn(7:0)
R/W-All ones
Table 47. ADCn-Upper-Thresh (Low Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
THRUn(7:0)
R/W
All ones
Sets 12-bit upper threshold value for the ADC_n channel in
straight binary format.
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7.6.11.2 ADCn-Upper-Thresh (High Byte) Register (address = 0x80 through 0x93) [reset = 0x0F]
Figure 100. ADCn-Upper-Thresh (High Byte) Register (R/W)
7
6
5
4
3
2
Reserved
R/W-All zeros
1
0
THRUn(11:8)
R/W-0xF
Table 48. ADCn-Upper-Thresh (High Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-4
Reserved
R/W
All zeros
Reserved for factory use.
3-0
THRUn(11:8)
R/W
0xF
Sets 12-bit upper threshold value for the ADC_n channel in
straight binary format.
7.6.11.3 ADCn-Lower-Thresh (Low Byte) Register (address = 0x80 through 0x93) [reset = 0x00]
Figure 101. ADCn-Lower-Thresh (Low Byte) Register (R/W)
7
6
5
4
3
2
1
0
THRLn(7:0)
R/W-All zeros
Table 49. ADCn-Lower-Thresh (Low Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
THRLn(7:0)
R/W
All zeros
Sets 12-bit lower threshold value for the ADC_n channel in
straight binary format.
7.6.11.4 ADCn-Lower-Thresh (High Byte) Register (address = 0x80 through 0x93) [reset = 0x00]
Figure 102. ADCn-Lower-Thresh (High Byte) Register (R/W)
7
6
5
4
3
2
Reserved
R/W-All zeros
1
0
THRLn(11:8)
R/W-All zeros
Table 50. ADCn-Lower-Thresh (High Byte) Register Field Descriptions Field Descriptions
Bit
Field
Type
Reset
Description
7-4
Reserved
R/W
All zeros
Reserved for factory use.
3-0
THRLn(11:8)
R/W
All zeros
Sets 12-bit lower threshold value for ADC_n channel in straight
binary format.
7.6.11.5 LT-Upper-Thresh (Low Byte) Register (address = 0x94) [reset = 0xFF]
Figure 103. LT-Upper-Thresh (Low Byte) Register (R/W)
7
6
5
4
3
2
1
0
THRU-LT(7:0)
R/W-All ones
Table 51. LT-Upper-Thresh (Low Byte) Register Field Descriptions
66
Bit
Field
Type
Reset
Description
7-0
THRU-LT(7:0)
R/W
All ones
Sets 12-bit upper threshold value for the local temperature
sensor in two’s complement format.
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7.6.11.6 LT-Upper-Thresh (High Byte) Register (address = 0x95) [reset = 0x07]
Figure 104. LT-Upper-Thresh (High Byte) Register (R/W)
7
6
5
4
3
2
Reserved
R/W-All zeros
1
0
THRU-LT(11:8)
R/W-0x7
Table 52. LT-Upper-Thresh (High Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-4
Reserved
R/W
All zeros
Reserved for factory use.
3-0
THRU-LT(11:8)
R/W
0x7
Sets 12-bit upper threshold value for the local temperature
sensor in two’s complement format.
7.6.11.7 LT-Lower-Thresh (Low Byte) Register (address = 0x96) [reset = 0x00]
Figure 105. LT-Lower-Thresh (Low Byte) Register (R/W
7
6
5
4
3
2
1
0
THRL-LT(7:0)
R/W-All zeros
Table 53. LT-Lower-Thresh (Low Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-0
THRL-LT(7:0)
R/W
All zeros
Sets 12-bit lower threshold value for the local temperature
sensor in two’s complement format.
7.6.11.8 LT-Lower-Thresh (High Byte) Register (address = 0x97) [reset = 0x08]
Figure 106. LT-Lower-Thresh (High Byte) Register (R/W)
7
6
5
4
3
Reserved
R/W-All zeros
2
1
0
THRL-LT(11:8)
R/W-0x8
Table 54. LT-Lower-Thresh (High Byte) Register Field Descriptions
Bit
Field
Type
Reset
Description
7-4
Reserved
R/W
All zeros
Reserved for factory use.
3-0
THRL-LT(11:8)
R/W
0x8
Sets 12-bit lower threshold value for the local temperature
sensor in two’s complement format.
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7.6.12 Alarm Hysteresis Configuration: Address 0xA0 and 0xA5
The hysteresis registers define the hysteresis in the out-of-range alarms.
7.6.12.1 ADCn-Hysteresis Register (address = 0xA0 through 0xA4) [reset = 0x08]
Figure 107. ADCn-Hysteresis Register (R/W)
7
Reserved
R/W-0
6
5
4
3
HYSTn(6:0)
R/W-0x08
2
1
0
Table 55. ADCn-Hysteresis Register Field Descriptions
Bit
7
6-0
Field
Type
Reset
Description
Reserved
R/W
0
Reserved for factory use.
HYSTn(6:0)
R/W
0x08
Hysteresis of general purpose ADC_n, 1 LSB per step
7.6.12.2 LT-Hysteresis Register (address = 0xA5) [reset = 0x08]
Figure 108. LT-Hysteresis Register (R/W)
7
6
Reserved
R/W-All zeros
5
4
3
2
HYST-LT(4:0)
R/W-0x08
1
0
Table 56. LT-Hysteresis Register Field Descriptions
Bit
Field
Type
Reset
Description
7-5
Reserved
R/W
All zeros
Reserved for factory use.
4-0
HYST-LT(4:0)
R/W
0x08
Hysteresis of local temperature sensor, 1°C per step. The range
is 0°C to 31°C.
7.6.13 Clear and Power-Down Registers: Address 0xB0 through 0XB4
7.6.13.1 DAC Clear 0 Register (address = 0xB0) [reset = 0x00]
Figure 109. DAC Clear 0 Register (R/W)
7
CLR-B7
R/W-0
6
CLR-B6
R/W-0
5
CLR-B5
R/W-0
4
CLR-B4
R/W-0
3
CLR-A3
R/W-0
2
CLR-A2
R/W-0
1
CLR-A1
R/W-0
0
CLR-A0
R/W-0
Table 57. DAC Clear 0 Register Field Descriptions
Bit
68
Field
Type
Reset
Description
7
CLR-B7
R/W
0
This register uses software to force the DAC into a clear state.
6
CLR-B6
R/W
0
5
CLR-B5
R/W
0
4
CLR-B4
R/W
0
3
CLR-A3
R/W
0
2
CLR-A2
R/W
0
1
CLR-A1
R/W
0
0
CLR-A0
R/W
0
If CLRn = 1, DAC_n is forced into a clear state.
If CLRn = 0, DAC_n is restored to normal operation.
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7.6.13.2 DAC Clear 1 Register (address = 0xB1) [reset = 0x00]
Figure 110. DAC Clear 1 Register (R/W)
7
CLR-D15
R/W-0
6
CLR-D14
R/W-0
5
CLR-D13
R/W-0
4
CLR-D12
R/W-0
3
CLR-C11
R/W-0
2
CLR-C10
R/W-0
1
CLR-C9
R/W-0
0
CLR-C8
R/W-0
Table 58. DAC Clear 1 Register Field Descriptions
Bit
Field
Type
Reset
Description
7
CLR-D15
R/W
0
This register uses software to force the DAC into a clear state.
6
CLR-D14
R/W
0
5
CLR-D13
R/W
0
4
CLR-D12
R/W
0
3
CLR-C11
R/W
0
2
CLR-C10
R/W
0
1
CLR-C9
R/W
0
0
CLR-C8
R/W
0
If CLRn = 1, DAC_n is forced into a clear state.
If CLRn = 0, DAC_n is restored to normal operation.
7.6.13.3 Power-Down 0 Register (address = 0xB2) [reset = 0x00]
Figure 111. Power-Down 0 Register (R/W)
7
PDAC-B7
R/W-0
6
PDAC-B6
R/W-0
5
PDAC-B5
R/W-0
4
PDAC-B4
R/W-0
3
PDAC-A3
R/W-0
2
PDAC-A2
R/W-0
1
PDAC-A1
R/W-0
0
PDAC-A0
R/W-0
Table 59. Power-Down 0 Register Field Descriptions
Bit
Field
Type
Reset
Description
7
PDAC-B7
R/W
0
6
PDAC-B6
R/W
0
5
PDAC-B5
R/W
0
4
PDAC-B4
R/W
0
3
PDAC-A3
R/W
0
2
PDAC-A2
R/W
0
1
PDAC-A1
R/W
0
After power-on or reset, all bits in the power-down register are
cleared to 0, and all the components controlled by this register
are either powered-down or off. The power-down register allows
the host to manage the AMC7836 power dissipation. When not
required, any of the DACs can be put into clamp mode and the
ADC and internal reference into an inactive low-power mode to
reduce current drain from the supply. The bits in the power-down
register control this power-down function. Set the respective bit
to 1 to activate the corresponding function.
0
PDAC-A0
R/W
0
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7.6.13.4 Power-Down 1 Register (address = 0xB3) [reset = 0x00]
Figure 112. Power-Down 1 Register (R/W)
7
PDAC-D15
R/W-0
6
PDAC-D14
R/W-0
5
PDAC-D13
R/W-0
4
PDAC-D12
R/W-0
3
PDAC-C11
R/W-0
2
PDAC-C10
R/W-0
1
PDAC-C9
R/W-0
0
PDAC-C8
R/W-0
Table 60. Power-Down 1 Register Field Descriptions
Bit
Field
Type
Reset
Description
7
PDAC-D15
R/W
0
6
PDAC-D14
R/W
0
5
PDAC-D13
R/W
0
4
PDAC-D12
R/W
0
3
PDAC-C11
R/W
0
2
PDAC-C10
R/W
0
1
PDAC-C9
R/W
0
After power-on or reset, all bits in the power-down register are
cleared to 0, and all the components controlled by this register
are either powered-down or off. The power-down register allows
the host to manage the AMC7836 power dissipation. When not
required, any of the DACs can be put into clamp mode and the
ADC and internal reference into an inactive low-power mode to
reduce current drain from the supply. The bits in the power-down
register control this power-down function. Set the respective bit
to 1 to activate the corresponding function.
0
PDAC-C8
R/W
0
7.6.13.5 Power-Down 2 Register (address = 0xB4) [reset = 0x00]
Figure 113. Power-Down 2 Register (R/W)
7
6
5
4
3
2
Reserved
R/W-All zeros
1
PREF
R/W-0
0
PADC
R/W-0
Table 61. Power-Down 2 Register Field Descriptions
70
Bit
Field
Type
Reset
Description
7-2
Reserved
R/W
All zeros
Reserved for factory use.
1
PREF
R/W
0
0
PADC
R/W
0
After power-on or reset, all bits in the power-down register are
cleared to 0, and all the components controlled by this register
are either powered-down or off. The power-down register allows
the host to manage the AMC7836 power dissipation. When not
required, any of the DACs can be put into clamp mode and the
ADC and internal reference into an inactive low-power mode to
reduce current drain from the supply. The bits in the power-down
register control this power-down function. Set the respective bit
to 1 to activate the corresponding function.
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7.6.14 ADC Trigger: Address 0xC0
7.6.14.1 ADC Trigger Register (address = 0xC0) [reset = 0x00]
Figure 114. ADC Trigger Register (R/W)
7
6
5
4
Reserved
R/W-All zeros
3
2
1
0
ICONV
R/W-0
Table 62. ADC Trigger Register Field Descriptions
Bit
Field
Type
Reset
Description
7-1
Reserved
R/W
All zeros
Reserved for factory use
ICONV
R/W
0
Internal ADC conversion bit.
0
Set this bit to 1 to start the ADC conversion internally. The bit is
automatically cleared to 0 after the ADC conversion starts.
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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 AMC7836 device is a highly integrated, low-power, analog monitoring and control solution that includes a
21-channel (12-bit) ADC, 16-channel (12-bit) DACs, eight GPIO, and a local temperature sensor. Although the
device can be used in many different closed-loop systems, including industrial control and test and
measurement, the device is largely used as a power amplifier controller in multi-channel RF communication
applications.
Power amplifiers (PAs) include transistor technologies that are extremely temperature sensitive, and require DC
biasing circuits to optimize RF performance, power efficiency, and stability. The AMC7836 device provides 16
DAC channels which can be used to adjust the power amplifier bias points in response to temperature changes.
The device also includes an internal local temperature sensor, and 21 ADC channels for general-purpose
monitoring.
Current and temperature sensing are typically implemented in power amplifier controller applications. PA drain
current sensing is implemented by measuring the differential voltage drop across a shunt resistor. Temperature
variations during PA operation can be detected either through the AMC7836 internal temperature sensor or
through remote temperature ICs or thermistors configured to interface with the ADC analog inputs available in
the device. Figure 115 shows the block diagram for these different systems.
AMC7836
GPIO
ADC
Digital Interface
MUX
Local
Temperature
Sensor
DAC
Current
Sense
Amplifier
Power
Power
¨9
Power
Amplifier
R(shunt)
Power
Amplifier
RF IN
RF IN
Temperature
Sensor
Heat Sink
Temperature Sensing
Heat Sink
Current Sensing
Figure 115. AMC7836 Example Control and Monitor System
72
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Application Information (continued)
8.1.1 Temperature Sensing Applications
The AMC7836 device contains one local temperature and five unipolar analog inputs that are easily configurable
to interface with remote temperature-sensor circuits. The integrated temperature sensor and analog input
registers automatically update with every conversion. Figure 116 shows an example of a remote temperature
sensor connection.
The selected temperature sensor is the LM50 device, a high precision integrated-circuit temperature sensor that
operates in the –40°C to 125°C temperature range using a single positive supply. The full-scale output of the
temperature sensor ranges from 100 mV to 1.75 V for the operational temperature range. In an extremely noisy
environment, additional filtering is recommended. A typical value for the bypass capacitor is 0.1 µF from the V+
pin to GND. A high-quality ceramic type NP0 or X7R is recommended because of optimal performance across
temperature and very low dissipation factor.
LM50
DVDD
4
V+
VO
3
LV_ADC15
1
NC
0.1 µF
GND
2
5
Figure 116. Temperature Sensing Application With LM50
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Application Information (continued)
8.1.2 Current Sensing Applications
In applications that require current sensing of the power amplifier, an external high-side current sense amplifier
can be added and configured to the unipolar ADC inputs. Figure 117 shows this design.
The LMP8480 device is a precision current sense device that amplifies the small differential voltage developed
across a current-sense resistor in the presence of high input common-mode voltages. The LMP8480 device
accepts input signals with a common-mode voltage range from 4 V to 76 V with a bandwidth of 270 kHz. The
LMP8480 device offers different fixed gain settings. The optimal gain setting is dependent on the accuracy
requirement of the application. To maintain precision over temperature, the output of the LMP8480 device should
be directly connected to the AMC7836 unipolar ADC inputs. If the output range of the LMP8480 device is scaled
by a voltage divider, as shown in Figure 117, an output amplifier may be required to drive the ADC unipolar input
to ensure a low impedance source. If the series resistance, in this case R4, is low enough then the buffer may
not be required because the LMP8480 device is capable of driving the input of the AMC7836 unipolar ADC
channel.
NOTE
The external resistors will cause some small error because of temperature drift and the
input bias current of the operation amplifier.
Figure 117 also shows a simple method to ensure proper power sequencing of the power amplifier by adding a
series PMOS transistor to the PA drain terminal. The activation of the PMOS transistor connects the PAVDD
voltage supply to the drain pin of the power amplifier. The PMOS transistor is driven with a voltage divider that
swings from the PAVDD voltage to PAVDD × (R2 / (R1 + R2)). The NMOS shown in Figure 117 is connected to a
microcontroller output that controls the state of the PMOS transistor.
PAVDD
R4
R1
VCC
VOUT
RSP
NC
+
ADC Input
R3
R(SENSE)
RSN
GND
LMP8480
R2
Drain
Gate
DAC Voltage
PC GPIO
PA
Source
Figure 117. Current-Sense Application With PMOS ON and OFF
74
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8.2 Typical Application
Figure 118 shows an example schematic incorporating the AMC7836 device.
DAC OUTPUTS connect to the gate (VG) of the PA modules
0.1 µF
AVEE
AVEE
AVCC
IOVDD
0.1 µF DVDD
IOVDD
AVDD
0.1 µF
0.1 µF
0.1 µF
49
AVDD
50
REF_CMP
DAC_C8
AVSSC
52 51
DAC_C9
DAC_C11
54 53
DAC_C10
55
AGND3
56
AVCC_CD
DAC_D13
58 57
DAC_D12
59
AVSSD
DAC_D14
IOVDD
2k
61 60
DAC_D15
1
62
DVDD
63
DGND
64
VDD
4.7 µF
AGND2
48
2
RESET
3
MISO
RESET
SDO
4
MOSI
SDI
47
5
SCLK
ADC_0
SCLK
46
6
Digital Control
CS
ADC_1
CS
ADC_2
7
8
9
10
GPIO
11
12
13
14
GPIO0 (ALARMIN)
ADC_3
GPIO1 (ALARMOUT)
ADC_4
GPIO2 (ADCTRIG)
ADC_5
AMC7836
GPIO3 (DAV)
GPIO4
ADC_6
GPIO5
ADC_7
GPIO6
LV_ADC16
GPIO7
LV_ADC17
LV_ADC18
LV_ADC19
LV_ADC20
ADC_8
GND
ADC_10
ADC_11
ADC_12
ADC_13
ADC_14
ADC_15
DAC_B7
DAC_B6
AVSSB
DAC_B5
DAC_B4
AGND1
AVCC_AB
DAC_A1
DAC_A3
DAC_A0
AVEE
16
DAC_A2
15
Thermal Pad
ADC_9
45
44
43
42
41
40
39
38
37
36
Unipolar
Monitor Connection
LV_ADC16 ±
LV_ADC20
35
34
33
Bipolar ADC inputs
connected to
PA module gate for
voltage monitoring
0
AVEE
18
17
19 20
21
22
23
25 26
24
0.1 µF
0.1 µF
Digital
GND
0.1 µF
27 28 29 30 31 32
Analog
GND
AVEE
AVCC
DAC OUTPUTS connect to the gate (VG) of the PA modules
Figure 118. AMC7836 Example Schematic
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Typical Application (continued)
8.2.1 Design Requirements
The AMC7836 example schematic uses the majority of the design parameters listed in Table 63.
Table 63. Design Parameters
DESIGN PARAMETER
EXAMPLE VALUE
AVCC
5V
AVEE
–12 V
IOVDD
3.3 V
DVDD
5V
AVDD
5V
AVSS banks
AVEE
ADC bipolar inputs
ADC[0-15]: –12.5 to 12.5 V input range
ADC unipolar inputs
LV_ADC[16-20]: 0 to 5 V range
DAC outputs
Sixteen Monotonic 12-bit DACs
Selectable ranges: 0 to 5 V, 0 to 10 V, –10 to 0 V or –5 to 0 V
Remote temperature sensing
IC temperature sensor (LM50) or thermistor
8.2.2 Detailed Design Procedure
Use the following parameters to facilitate the design process:
• AVCC and AVEE voltage values
• ADC input voltage range
• DAC Output voltage Ranges
8.2.2.1 ADC Input Conditioning
The AMC7836 device has an ADC with 21 analog inputs for external voltage sensing. Sixteen of these inputs are
bipolar and the other five are unipolar. The bipolar inputs (ADC_0 through ADC_15) range is –12.5 to 12.5 V,
and the unipolar analog inputs (LV_ADC16 through LV_ADC20) range is 0 to 2 × Vref. The ADC operates from
an internal 2.5 V reference (Vref, measured at the REF_CMP pin). For additional noise filtering, a 4.7-µF
capacitor should be connected between the REF_CMP and AGND2 pins. A high-quality ceramic type NP0 or
X7R is recommended because of the optimal performance of the capacitor across temperature and very-low
dissipation factor.
The ADC timing signals are driven from an on-chip temperature compensated 4-MHz oscillator. The on-chip
oscillator is primarily responsible for the sampling frequency of the ADC. The sampling frequency of the ADC is
dynamic and dependent on the acquisition and conversion time of each channel. Table 64 lists the relationship
between the total update time and the internal oscillator frequency.
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Table 64. ADC Conversion Rate and Total Update Number of Clocks
ADC CONVERSION
RATE
00
01
10
11
ADC INPUT CHANNEL
ACQUISITION CLOCKS
CONVERSION CLOCKS
tS (ACQUISITION +
CONVERSION)
NUMBER OF CLOCKS
Bipolar
124.5
13.5
138
Unipolar
32.5
13.5
46
Internal Temperature
Sensor
—
—
1025
Bipolar
124.5
13.5
138
Unipolar
78.5
13.5
92
Internal Temperature
Sensor
—
—
1025
Bipolar
124.5
13.5
138
Unipolar
124.5
13.5
138
Internal Temperature
Sensor
—
—
1025
Bipolar
262.5
13.5
276
Unipolar
262.5
13.5
276
Internal Temperature
Sensor
—
—
1025
The minimum and maximum oscillator frequency specifications in conjunction with the number of clocks required
for the unipolar, bipolar and temperature sensor inputs should be applied to Equation 5 to calculate the total
update time range.
(BCLK u #BCH UCLK u #UCH TCLK u # TCH )
TS
¦OSC
where
•
•
•
•
•
•
•
•
TS is the total update time
BCLK is the total bipolar clocks
#BCH is the number of active bipolar inputs
UCLK is the total unipolar clocks
#UCH is the number of active unipolar inputs
TCKL is the total internal temperature-sensor clocks
#TCH is the number of active internal temperature sensor channels; either 1 or 0
ƒOSC is the internal oscillator frequency
(5)
The following is an example of a complete calculation of the total update time range. In this example, the ADC
conversion rate is set to 00 and the following ADC input channels are used:
• Bipolar channels: ADC_1 through ADC_5 (5 active bipolar channels)
• Unipolar channels: LV_ADC16 through LV_ADC18 (3 active unipolar channels)
• Internal temperature sensor (1 active temperature channel)
Table 64 gives the total number of clocks required for each ADC input under the example conditions.
For the minimum specified oscillator frequency of 3.7 MHz, and with the ADC conversion rate set to 00, use
Equation 6 to calculate the total maximum update time for this example.
(138 u 5 46 u 3 1025 u 1)
TS
500.811 µs
3.7 MHz
(6)
For the maximum specified oscillator frequency of 4.3 MHz, use Equation 7 to calculate the total minimum
update time for this example.
(138 u 5 46 u 3 1025 u 1)
TS
430.93 µs
4.3 MHz
(7)
Therefore, the total update time range is 430.93 µs to 500.811 µs.
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During the conversion, the input current per channel varies with the total update time which is determined by the
number and type of channels (NCH) and the conversion rate setting of the CONV-RATE bit in the ADC
configuration register (address 0x10).
NOTE
The source of the analog input voltage must be able to charge the input capacitance to a
12-bit settling level within the acquisition time.
8.2.2.2 DAC Output Range Selection
The AMC7836 device includes 16 DACs split into four groups, each with four DACs. All of the DACs in a given
group share the same output voltage range. The output range for each DAC group is independent and is
programmable to either –10 to 0 V, –5 to 0 V, 0 to 10 V or 0 to 5 V. The DAC output ranges are configured by
following the configuration settings listed in Table 1.
Each DAC includes an output buffer is capable of generating rail-to rail voltages. The Electrical Characteristics:
DAC table lists the maximum source and sink capability of this internal amplifier. The graphs in the Application
Curves section show the relationship of both stability and settling time with different capacitive loading structures.
8.2.3 Application Curves
15
15
10nF, Rising Edge
200pF, Falling Edge
10
DAC Output Error (LSB)
10
DAC Output Error (LSB)
10nF, Falling Edge
200pF, Rising Edge
5
0
-5
-10
5
0
-5
-10
-15
-15
0
5
10
15
20
Time (µs)
25
0
Code 0x400 to 0xC00 to within ½ LSB
5
10
15
Time (µs)
C001
20
25
C001
Code 0xC00 to 0x400 to within ½ LSB
Figure 119. DAC Settling Time vs Load Capacitance
Figure 120. DAC Settling Time vs Load Capacitance
9 Power Supply Recommendations
The preferred (not required) pin order for applying power is IOVDD, DVDD and AVDD, AVCC and lastly AVEE,
AVSSB, AVSSC, and AVSSD.When power sequencing, ensure that all digital pins are not powered or in an active
state while the IOVDD pin ramps. Proper sequencing of the digital pins can be accomplished by attaching 10-kΩ
pullup resistors to the IOVDD pin, or pulldown resistors to the DGND pin. See the supply voltage ranges in the
Recommended Operating Conditions table.
In applications where a negative voltage is applied to AVEE, AVSSB, AVSSC, and AVSSD first, the user may notice
some small negative voltages at other supply pins, such as the AVDD, DVDD, and AVCC pins. The negative
voltages at the supply pins may exceed the values listed in the Absolute Maximum Ratings table, but because
these voltages are created from intrinsic circuitry, the voltage levels are safe for operation.
In the case where all DAC outputs are in clamp state with AVEE = AVSSB = AVSSC = AVSSD = –12 V, the
negative voltage observed on the other supply pins can be as low as –620 mV.
Although these negative voltages are observed on the pins, the user must still adhere to the guidelines specified
in the Absolute Maximum Ratings table and verify that the inputs are driven within the range specified in the
table. The user should also ensure that current is only applied when operating with voltages between the ranges
listed in the Absolute Maximum Ratings table.
78
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In applications where the DAC channels are driving a large capacitive load and the output changes significantly
(a full scale transition, for instance), the output current of the affected channels may drive to the short circuit
current value as described in the specification table (see Table 64) while the capacitive load is being charged.
This temporary increase in output current may inadvertently cause the AVCC or AVSS to collapse, potentially
resulting in a POR event. It is recommended that the power supply solution for AVCC and AVSS be capable of
supplying short circuit current for all DAC channels with capacitive loads simultaneously to ensure proper device
performance.
9.1 Device Reset Options
9.1.1 Power-on-Reset (POR)
The AMC7836 device includes a power-on reset (POR) function. After all supplies have been established, a POR
event is issued. The POR causes all registers to initialize to the default values, and communication with the
device is valid only after a 250 µs power-on reset delay.
The default operation is power-down mode (register 0x02) in which the device is non-operational except for the
communication interface as determined by the power-down registers. Before enabling normal operation, a
hardware reset should be issued.
A power failure on DVDD, AVDD, AVCC or IOVDD has the potential to initiate a power-on-reset event. As long as
DVDD, AVDD, AVCC, and IOVDD remain above the minimum recommended operating conditions a power failure
event will not occur. When any of these supplies drops below the minimum recommended operating condition
the device may or may not imitate a POR. In this case, issuing a hardware reset or proper POR is recommended
to resume proper operation. To ensure a proper POR event, the DVDD supply must fall below 750 mV. If the
DVDD supply falls below 2.7 V a hardware reset or proper POR must be issued.
9.1.2 Hardware Reset
A device hardware reset event is initiated by a minimum 20-ns logic low on the RESET pin. A hardware reset
causes all registers to initialize to the default values and communication with the device is valid only after a 250µs reset delay.
9.1.2.1 Software Reset
A software reset event is initiated by setting the SOFT-RESET bit in the interface configuration 0 register (0x00).
A software reset causes all registers, except 0x00 and 0x01, to initialize to the default values and communication
with the device is valid only after a 100-ns delay.
10 Layout
10.1 Layout Guidelines
•
•
•
•
•
All power supply pins should be bypassed to ground with a low-ESR ceramic bypass capacitor. The typical
recommended bypass capacitor has a value of 10-µF and is ceramic with a X7R or NP0 dielectric.
To minimize interaction between the analog and digital return currents, the digital and analog sections should
have separate ground planes that eventually connect at some point.
To reduce noise on the internal reference, a 4.7-µF capacitor is recommended between the REF_CMP pin
and ground.
A high-quality ceramic type NP0 or X7R capacitor is recommended because of the optimal performance
across temperature very-low dissipation factor of the capacitor.
The digital and analog sections should have proper placement with respect to the digital pins and analog pins
of the AMC7836 device (see Figure 122). The separation of analog and digital blocks allows for better design
and practice as it ensures less coupling into neighboring blocks and minimizes the interaction between analog
and digital return currents.
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0.1 µF
Bypass Capacitor
close to supply pins: DVDD,
AVSS, AVSS and AVDD
0.1 µF
0.1 µF
10.2 Layout Example
Bypass Capacitor
close to AVCC
0.1 µF
DAC_C10
AVSS_C
DAC_C9
DAC_C8
AVDD
REF_CMP
52
51
50
49
AVCC_CD
57
53
DAC_D12
58
54
DAC_D13
DAC_C11
AVSS_D
59
55
DAC_D14
60
AGND3
DAC_D15
61
56
DVDD
62
DGND
64
0.1 µF
63
0.1 µF
4.7 µF
Compensation Capacitor
close to REF_CMP pin and
connect to AGND2
AGND2
ADC_7
GPIO3/DAV
10
39
LV_ADC16
GPIO4
11
38
LV_ADC17
GPIO5
12
37
LV_ADC18
GPIO6
13
36
LV_ADC19
GPIO7
14
35
LV_ADC20
DAC_A0
15
34
ADC_8
DAC_A1
16
33
ADC_9
ADC_10
ADC_15
AVSS_B
DAC_B5
DAC_B4
AGND1
AVCC_AB
32
40
30
9
31
ADC_6
GPIO2/ADCTRIG
ADC_11
41
ADC_12
8
29
ADC_5
GPIO1/ALARMOUT
ADC_13
42
28
7
27
ADC_4
GPIO0/ALARMIN
ADC_14
43
26
6
DAC_B7
ADC_3
CS
25
44
DAC_B6
5
24
ADC_2
SCLK
23
45
22
4
21
ADC_1
SDI
20
46
19
3
DAC_A3
ADC_0
SDO
18
47
17
48
2
AVEE
1
DAC_A2
IOVDD
RESET
0.1 µF
VRANGE_
B
Bypass Capacitor
close to AVEE, AVCC,
and AVSS
0.1 µF
0.1 µF
49
50
51
52
53
55
54
56
59
57
58
60
61
63
62
1
48
2
47
3
46
4
45
5
44
6
43
7
42
8
41
9
40
10
39
11
38
12
37
13
36
32
31
30
29
28
26
27
25
22
24
23
21
20
33
18
16
19
35
34
17
14
15
ANALOG
DIGITAL
64
Figure 121. AMC7836 Example Board Layout
Figure 122. AMC7836 Example Board Layout — Component Placement
80
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11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation see the following:
• LMP8480 / LMP8481 Precision 76V High-Side Current Sense Amplifiers with Voltage Output, SNVS829
• LM50/LM50-Q1 SOT-23 Single-Supply Centigrade Temperature Sensor, SNIS118
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.4 Trademarks
PowerPAD, E2E are trademarks of Texas Instruments.
All other trademarks are the property of their respective owners.
11.5 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.
11.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 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.
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PACKAGE OPTION ADDENDUM
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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)
AMC7836IPAP
ACTIVE
HTQFP
PAP
64
160
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 125
AMC7836
AMC7836IPAPR
ACTIVE
HTQFP
PAP
64
1000
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 125
AMC7836
(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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