SBASA22A september   2022  – july 2023 ADS131B26-Q1

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 ADC3y
      7. 8.3.7 General-Purpose Digital Inputs and Outputs (GPIO0 to GPIO4)
        1. 8.3.7.1 GPIOx PWM Output Configuration
        2. 8.3.7.2 GPIOx PWM Input Readback
      8. 8.3.8 General-Purpose Digital Inputs and Outputs (GPIO0A, GPIO1A, GPIO0B, GPIO1B)
      9. 8.3.9 Monitors and Diagnostics
        1. 8.3.9.1  Supply Monitors
        2. 8.3.9.2  Clock Monitors
        3. 8.3.9.3  Digital Monitors
          1. 8.3.9.3.1 Register Map CRC
          2. 8.3.9.3.2 Memory Map CRC
          3. 8.3.9.3.3 GPIO Readback
        4. 8.3.9.4  Communication Monitors
        5. 8.3.9.5  Fault Flags and Fault Masking
        6. 8.3.9.6  FAULT Pin
        7. 8.3.9.7  Diagnostics and Diagnostic Procedure
        8. 8.3.9.8  Indicators
        9. 8.3.9.9  Conversion and Sequence Counters
        10. 8.3.9.10 Supply Voltage Readback
        11. 8.3.9.11 Temperature Sensors (TSA, TSB)
        12. 8.3.9.12 Test DACs (TDACA, TDACB)
        13. 8.3.9.13 Open-Wire Detection
        14. 8.3.9.14 Missing Host Detection and MHD Pin
        15. 8.3.9.15 Overcurrent Comparators (OCCA, OCCB)
          1. 8.3.9.15.1 OCCA and OCCB Pins
          2. 8.3.9.15.2 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 and ADC3y 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, ADC2A, ADC2B, ADC3A, and ADC3B 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 Other Voltage Measurements
        4. 9.2.2.4 Shunt Temperature Measurement
        5. 9.2.2.5 Analog Output Temperature Sensor 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
8.5.1.2.7 SPI Timeout

The ADS131B26-Q1 implements an SPI timeout feature that measures the time between the CSn falling and CSn rising edge within a frame. If the CSn rising edge does not occur within the SPI timeout period (tTIMEOUT) after the CSn falling edge, then the SPI_TIMEOUTn flag is set in the following frame. When a timeout occurs, the rest of the SPI frame on SDI is ignored before the rising edge of CSn. A new SPI transaction starts at the next CSn falling edge. Enable or disable the SPI timeout using the TIMEOUT_EN bit.

If the SPI times out after a complete frame was transmitted on SDI and SDO already, then there is no impact to the SPI communication, however the SPI_TIMEOUTn flag does still set in that case to indicate that the CSn signal was held low for too long.

If the SPI times out before a complete frame is transmitted on SDI and SDO, then there is potential impact to the SPI communication in certain situations:

  • NULL command: No effect.
  • RESET command: Does not execute until the complete output CRC word is clocked out on SDO before the SPI times out.
  • LOCK, UNLOCK, RREG commands: Do execute if at least the command and command CRC words are received on SDI before the SPI times out.
  • WREG command: Does execute if at least the command, command CRC, register data, and register data CRC words are received on SDI before the SPI times out.
  • DRDYn pin: The DRDYn pin only transitions high after the conversion data word for ADC3B is clocked out on SDO before the SPI times out. Otherwise, the device assumes the host did not receive the latest conversion data and the DRDYn pin stays low.