SBASAP8A december   2022  – august 2023 ADS131B23

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Switching Characteristics
    8. 6.8 Timing Diagram
    9. 6.9 Typical Characteristics
  8. 7 Parameter Measurement Information
    1. 7.1 Offset Drift Measurement
    2. 7.2 Gain Drift Measurement
    3. 7.3 Noise Performance
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Naming Conventions
      2. 8.3.2 Precision Voltage References (REFA, REFB)
      3. 8.3.3 Clocking (MCLK, OSCM, OSCD)
      4. 8.3.4 ADC1y
        1. 8.3.4.1 ADC1y Input Multiplexer
        2. 8.3.4.2 ADC1y Programmable Gain Amplifier (PGA)
        3. 8.3.4.3 ADC1y ΔΣ Modulator
        4. 8.3.4.4 ADC1y Digital Filter
        5. 8.3.4.5 ADC1y Offset and Gain Calibration
        6. 8.3.4.6 ADC1y Conversion Data
      5. 8.3.5 ADC2y
        1. 8.3.5.1 ADC2y Input Multiplexer
        2. 8.3.5.2 ADC2y Programmable Gain Amplifier (PGA)
        3. 8.3.5.3 ADC2y ΔΣ Modulator
        4. 8.3.5.4 ADC2y Digital Filter
        5. 8.3.5.5 ADC2y Offset and Gain Calibration
        6. 8.3.5.6 ADC2y Sequencer
        7. 8.3.5.7 VCMy Buffers
        8. 8.3.5.8 ADC2y Measurement Configurations
        9. 8.3.5.9 ADC2y Conversion Data
      6. 8.3.6 General-Purpose Digital Inputs and Outputs (GPIO0 to GPIO4)
        1. 8.3.6.1 GPIOx PWM Output Configuration
        2. 8.3.6.2 GPIOx PWM Input Readback
      7. 8.3.7 General-Purpose Digital Inputs and Outputs (GPIO0A, GPIO1A, GPIO0B, GPIO1B)
      8. 8.3.8 Monitors and Diagnostics
        1. 8.3.8.1  Supply Monitors
        2. 8.3.8.2  Clock Monitors
        3. 8.3.8.3  Digital Monitors
          1. 8.3.8.3.1 Register Map CRC
          2. 8.3.8.3.2 Memory Map CRC
          3. 8.3.8.3.3 GPIO Readback
        4. 8.3.8.4  Communication Monitors
        5. 8.3.8.5  Fault Flags and Fault Masking
        6. 8.3.8.6  FAULT Pin
        7. 8.3.8.7  Diagnostics and Diagnostic Procedure
        8. 8.3.8.8  Indicators
        9. 8.3.8.9  Conversion and Sequence Counters
        10. 8.3.8.10 Supply Voltage Readback
        11. 8.3.8.11 Temperature Sensor (TSA)
        12. 8.3.8.12 Test DACs (TDACA, TDACB)
        13. 8.3.8.13 Open-Wire Detection
        14. 8.3.8.14 Missing Host Detection and MHD Pin
        15. 8.3.8.15 Overcurrent Comparators (OCCA, OCCB)
          1. 8.3.8.15.1 OCCA and OCCB Pins
          2. 8.3.8.15.2 Overcurrent Indication Response Time
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power-Up and Reset
        1. 8.4.1.1 Power-On Reset (POR)
        2. 8.4.1.2 RESETn Pin
        3. 8.4.1.3 RESET Command
      2. 8.4.2 Operating Modes
        1. 8.4.2.1 Active Mode
        2. 8.4.2.2 Standby Mode
        3. 8.4.2.3 Power-Down Mode
      3. 8.4.3 ADC Conversion Modes
        1. 8.4.3.1 ADC1y Conversion Modes
          1. 8.4.3.1.1 Continuous-Conversion Mode
          2. 8.4.3.1.2 Single-Shot Conversion Mode
          3. 8.4.3.1.3 Global-Chop Mode
            1. 8.4.3.1.3.1 Overcurrent Indication Response Time in Global-Chop Mode
        2. 8.4.3.2 ADC2y Sequencer Operation and Sequence Modes
          1. 8.4.3.2.1 Continuous Sequence Mode
          2. 8.4.3.2.2 Single-Shot Sequence Mode
          3. 8.4.3.2.3 Synchronized Single-Shot Sequence Mode Based on ADC1y Conversion Starts
    5. 8.5 Programming
      1. 8.5.1 Serial Interface
        1. 8.5.1.1 Serial Interface Signals
          1. 8.5.1.1.1 Chip Select (CSn)
          2. 8.5.1.1.2 Serial Data Clock (SCLK)
          3. 8.5.1.1.3 Serial Data Input (SDI)
          4. 8.5.1.1.4 Serial Data Output (SDO)
          5. 8.5.1.1.5 Data Ready (DRDYn)
        2. 8.5.1.2 Serial Interface Communication Structure
          1. 8.5.1.2.1 SPI Communication Frames
          2. 8.5.1.2.2 SPI Communication Words
          3. 8.5.1.2.3 STATUS Word
          4. 8.5.1.2.4 Communication Cyclic Redundancy Check (CRC)
          5. 8.5.1.2.5 Commands
            1. 8.5.1.2.5.1 NULL (0000 0000 0000 0000b)
            2. 8.5.1.2.5.2 RESET (0000 0000 0001 0001b)
            3. 8.5.1.2.5.3 LOCK (0000 0101 0101 0101b)
            4. 8.5.1.2.5.4 UNLOCK (0000 0110 0101 0101b)
            5. 8.5.1.2.5.5 WREG (011a aaaa aaa0 0nnnb)
            6. 8.5.1.2.5.6 RREG (101a aaaa aaan nnnnb)
          6. 8.5.1.2.6 SCLK Counter
          7. 8.5.1.2.7 SPI Timeout
          8. 8.5.1.2.8 Reading ADC1A, ADC1B, and ADC2A Conversion Data
          9. 8.5.1.2.9 DRDYn Pin Behavior
    6. 8.6 Register Map
      1. 8.6.1 Registers
  10. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Unused Inputs and Outputs
      2. 9.1.2 Minimum Interface Connections
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Current-Shunt Measurement
        2. 9.2.2.2 Battery-Pack Voltage Measurement
        3. 9.2.2.3 Shunt Temperature Measurement
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
      1. 9.3.1 Power-Supply Options
        1. 9.3.1.1 Single Unregulated External 4-V to 16-V Supply (3.3-V Digital I/O Levels)
        2. 9.3.1.2 Single Regulated External 3.3-V Supply (3.3-V Digital IO Levels)
        3. 9.3.1.3 Single Regulated External 5-V Supply (5-V Digital I/O Levels)
      2. 9.3.2 Power-Supply Sequencing
      3. 9.3.3 Power-Supply Decoupling
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.4.3.2 ADC2y Sequencer Operation and Sequence Modes

In contrast to ADC1y, conversions on ADC2y are controlled by means of a channel sequencer. Figure 8-22 depicts a flow chart of the sequencer operation. The ADC2y sequencer has up to 16 sequence steps that are individually enabled or disabled using the SEQ2y_STEPn_EN bits (n = 0 to 15). Each sequence step corresponds to one single conversion of ADC2y, which means up to 16 different measurements can be taken in one sequence run. The SEQ2y_STEPn_CFG registers configure the PGA gain, and the positive and negative input for the PGA for every sequence step. When a sequence is started, the sequencer steps through all enabled sequence steps, always starting with step 0. The sequencer ignores sequence steps that are disabled. One conversion is taken by ADC2y in each step before the sequencer configures ADC2y for the next step in the sequence. After the sequencer configures ADC2y for the next sequence step, the sequencer adds a programmable delay before starting the conversion to allow for settling of the input signal. The MUX2y_DELAY[2:0] bits select the delay time globally for all sequence steps. The time required to complete a sequence is given by Equation 22:

Equation 22. tSEQ = N × (tMUX_DELAY + tCONVERSION)

where:

  • N is the number of enabled steps
  • tMUX_DELAY is the multiplexer delay time
  • tCONVERSION is the conversion time of ADC2y

While a sequence is ongoing, the SEQ2y_ACTIVE bit is set in the STATUS register.

Do not make any changes to registers in the address range from 0x8C to 0x9F while ADC2A is enabled.

To avoid false sequencer starts, follow this procedure to configure and start the sequencer:

  1. Disable ADC2y by setting ADC2y_EN = 0b, or alternatively put the device into standby mode
  2. Configure the ADC2y sequencer register bits
  3. Enable ADC2y by setting ADC2y_EN = 1b, or alternatively put the device back into active mode
  4. Start the sequence by setting the SEQ2y_START bit

Setting the SEQ2y_START bit while ADC2y is disabled does not start a sequence.

Conversion data for the sequence steps of ADC2y are 16 bits and (in contrast to ADC1y conversion data) are stored in the user register space (register addresses 10h to 1Fh). The conversion data for sequence step n are stored in the corresponding SEQ2y_STEPn_DATA register. Conversion data for a sequence step that is disabled are set to 0000h. Read ADC2y conversion data using the register read command.

The conversion data of all SEQ2y_STEPn_DATA registers only update when a sequence run of ADC2y completes. While a sequence run is ongoing, the conversion data of the previous sequence run are read from the SEQ2y_STEPn_DATA registers. There is no data corruption or mix of data from two different sequence runs, even when a sequence completes while the SEQ2y_STEPn_DATA registers are read.

The ADC2y sequencer offers three sequence modes:

  • Continuous sequence mode
  • Single-shot sequence mode
  • Synchronized single-shot sequence mode based on ADC1y conversion starts

The SEQ2y_MODE[1:0] bits select the sequence mode for ADC2y.

GUID-20211223-SS0I-0S25-NRCK-DPBTKLN7662L-low.svg Figure 8-22 ADC2y Sequencer Flow Chart