ZHCSTD7A December   2021  – November 2023 BQ79631-Q1

PRODUCTION DATA  

  1.   1
  2. 特性
  3. 应用
  4. 说明
  5. Revision History
  6. 说明(续)
  7. Pin Configuration and Functions
  8. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  9. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Measurement System
        1. 8.3.1.1 Voltage Measurement System
          1. 8.3.1.1.1 Main ADC
            1. 8.3.1.1.1.1 VS Voltage Measurements
              1. 8.3.1.1.1.1.1 Analog Front End
              2. 8.3.1.1.1.1.2 VS Channel Measurements
              3. 8.3.1.1.1.1.3 Post-ADC Digital LPF
              4. 8.3.1.1.1.1.4 SRP and SRN Measurements
            2. 8.3.1.1.1.2 Temperature Measurements
              1. 8.3.1.1.1.2.1 DieTemp1 Measurement
              2. 8.3.1.1.1.2.2 GPIOs and TSREF Measurements
            3. 8.3.1.1.1.3 Main ADC Operation Control
              1. 8.3.1.1.1.3.1 Operation Modes and Status
          2. 8.3.1.1.2 AUX ADC
            1. 8.3.1.1.2.1 AUX Voltage Measurements
              1. 8.3.1.1.2.1.1 AUX Analog Front End
              2. 8.3.1.1.2.1.2 AUX Channel Measurements
            2. 8.3.1.1.2.2 AUX Temperature Measurements
              1. 8.3.1.1.2.2.1 DieTemp2 Measurement
              2. 8.3.1.1.2.2.2 AUX GPIO Measurements
            3. 8.3.1.1.2.3 MISC Measurements
            4. 8.3.1.1.2.4 AUX ADC Operation Control
          3. 8.3.1.1.3 Synchronization Between MAIN and AUX ADC Measurements
        2. 8.3.1.2 Current Sense ADC
      2. 8.3.2 OVUV Detection
        1. 8.3.2.1 OVUV Operation Modes
        2. 8.3.2.2 OVUV Control and Status
          1. 8.3.2.2.1 OVUV Control
          2. 8.3.2.2.2 OVUV Status
      3. 8.3.3 Power Supplies
        1. 8.3.3.1 AVAO_REF and AVDD_REF
        2. 8.3.3.2 LDOIN
        3. 8.3.3.3 AVDD
        4. 8.3.3.4 DVDD
        5. 8.3.3.5 CVDD and NEG5V
        6. 8.3.3.6 TSREF
      4. 8.3.4 GPIO Configuration
      5. 8.3.5 Communication, OTP, Diagnostic Control
        1. 8.3.5.1 Communication
          1. 8.3.5.1.1 Serial Interface
            1. 8.3.5.1.1.1 UART Physical Layer
              1. 8.3.5.1.1.1.1 UART Transmitter
              2. 8.3.5.1.1.1.2 UART Receiver
              3. 8.3.5.1.1.1.3 COMM CLEAR
            2. 8.3.5.1.1.2 Command and Response Protocol
              1. 8.3.5.1.1.2.1 Transaction Frame Structure
                1. 8.3.5.1.1.2.1.1 Frame Initialization Byte
                2. 8.3.5.1.1.2.1.2 Device Address Byte
                3. 8.3.5.1.1.2.1.3 Register Address Bytes
                4. 8.3.5.1.1.2.1.4 Data Bytes
                5. 8.3.5.1.1.2.1.5 CRC Bytes
                6. 8.3.5.1.1.2.1.6 Calculating Frame CRC Value
                7. 8.3.5.1.1.2.1.7 Verifying Frame CRC
              2. 8.3.5.1.1.2.2 Transaction Frame Examples
                1. 8.3.5.1.1.2.2.1 Single Device Read/Write
                2. 8.3.5.1.1.2.2.2 Stack Read/Write
                3. 8.3.5.1.1.2.2.3 Broadcast Read/Write
                4. 8.3.5.1.1.2.2.4 Broadcast Write Reverse Direction
          2. 8.3.5.1.2 Daisy-Chain Interface
            1. 8.3.5.1.2.1 Daisy-Chain Transmitter and Receiver Functionality
            2. 8.3.5.1.2.2 Daisy-Chain Protocol
          3. 8.3.5.1.3 Start Communication
            1. 8.3.5.1.3.1 Identify Base and Stack
            2. 8.3.5.1.3.2 Auto-Addressing
              1. 8.3.5.1.3.2.1 Setting Up the Device Addresses
              2. 8.3.5.1.3.2.2 Setting Up COMM_CTRL[STACK_DEV] and [TOP_STACK]
              3. 8.3.5.1.3.2.3 Storing Device Address to OTP
            3. 8.3.5.1.3.3 Synchronize Daisy-Chain DLL
            4. 8.3.5.1.3.4 Ring Communication
          4. 8.3.5.1.4 Communication Timeout
            1. 8.3.5.1.4.1 Short Communication Timeout
            2. 8.3.5.1.4.2 Long Communication Timeout
          5. 8.3.5.1.5 Communication Debug Mode
          6. 8.3.5.1.6 Multidrop Configuration
          7. 8.3.5.1.7 SPI Master
          8. 8.3.5.1.8 SPI Loopback
        2. 8.3.5.2 Fault Handling
          1. 8.3.5.2.1 Fault Status Hierarchy
            1. 8.3.5.2.1.1 Debug Registers
          2. 8.3.5.2.2 Fault Masking and Reset
            1. 8.3.5.2.2.1 Fault Masking
            2. 8.3.5.2.2.2 Fault Reset
          3. 8.3.5.2.3 Fault Signaling
            1. 8.3.5.2.3.1 Fault Status Transmitting in ACTIVE Mode
            2. 8.3.5.2.3.2 Fault Status Transmitting in SLEEP Mode
            3. 8.3.5.2.3.3 Heartbeat and Fault Tone
        3. 8.3.5.3 Nonvolatile Memory
          1. 8.3.5.3.1 OTP Page Status
          2. 8.3.5.3.2 OTP Programming
        4. 8.3.5.4 Diagnostic Control/Status
          1. 8.3.5.4.1 Power Supplies Check
            1. 8.3.5.4.1.1 Power Supply Diagnostic Check
            2. 8.3.5.4.1.2 Power Supply BIST
          2. 8.3.5.4.2 Thermal Shutdown and Warning Check
            1. 8.3.5.4.2.1 Thermal Shutdown
            2. 8.3.5.4.2.2 Thermal Warning
          3. 8.3.5.4.3 Oscillators Watchdog
          4. 8.3.5.4.4 OTP Error Check
            1. 8.3.5.4.4.1 OTP CRC Test and Faults
            2. 8.3.5.4.4.2 OTP Margin Read
            3. 8.3.5.4.4.3 Error Check and Correct (ECC) OTP
          5. 8.3.5.4.5 OVUV Detection Check
            1. 8.3.5.4.5.1 Parity Check
            2. 8.3.5.4.5.2 OVUV DAC Check
            3. 8.3.5.4.5.3 OVUV Protector BIST
          6. 8.3.5.4.6 Diagnostic Through ADC Comparison
            1. 8.3.5.4.6.1 VS Voltage Measurement Check
            2. 8.3.5.4.6.2 Temperature Measurement Check
            3. 8.3.5.4.6.3 VS and AUX Open Wire Check
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power Modes
        1. 8.4.1.1 SHUTDOWN Mode
          1. 8.4.1.1.1 Exit SHUTDOWN Mode
          2. 8.4.1.1.2 Enter SHUTDOWN Mode
        2. 8.4.1.2 SLEEP Mode
          1. 8.4.1.2.1 Exit SLEEP Mode
          2. 8.4.1.2.2 Enter SLEEP Mode
        3. 8.4.1.3 ACTIVE Mode
          1. 8.4.1.3.1 Exit ACTIVE Mode
          2. 8.4.1.3.2 Enter ACTIVE Mode From SHUTDOWN Mode
          3. 8.4.1.3.3 Enter ACTIVE Mode From SLEEP Mode
      2. 8.4.2 Device Reset
      3. 8.4.3 Ping and Tone
        1. 8.4.3.1 Ping
        2. 8.4.3.2 Tone
        3. 8.4.3.3 Ping and Tone Propagation
    5. 8.5 Register Maps
      1. 8.5.1 OTP Shadow Register Summary
      2. 8.5.2 Read/Write Register Summary
      3. 8.5.3 Read-Only Register Summary
      4. 8.5.4 Register Field Descriptions
        1. 8.5.4.1  Device Addressing Setup
          1. 8.5.4.1.1 DIR0_ADDR_OTP
          2. 8.5.4.1.2 DIR1_ADDR_OTP
          3. 8.5.4.1.3 CUST_MISC1 through CUST_MISC8
          4. 8.5.4.1.4 DIR0_ADDR
          5. 8.5.4.1.5 DIR1_ADDR
        2. 8.5.4.2  Device ID and Scratch Pad
          1. 8.5.4.2.1 PARTID
          2. 8.5.4.2.2 DEV_REVID
          3. 8.5.4.2.3 DIE_ID1 through DIE_ID9
        3. 8.5.4.3  General Configuration and Control
          1. 8.5.4.3.1  DEV_CONF
          2. 8.5.4.3.2  PWR_TRANSIT_CONF
          3. 8.5.4.3.3  COMM_TIMEOUT_CONF
          4. 8.5.4.3.4  TX_HOLD_OFF
          5. 8.5.4.3.5  STACK_RESPONSE
          6. 8.5.4.3.6  COMM_CTRL
          7. 8.5.4.3.7  CONTROL1
          8. 8.5.4.3.8  CONTROL2
          9. 8.5.4.3.9  CUST_CRC_HI
          10. 8.5.4.3.10 CUST_CRC_LO
          11. 8.5.4.3.11 CUST_CRC_RSLT_HI
          12. 8.5.4.3.12 CUST_CRC_RSLT_LO
        4. 8.5.4.4  Operation Status
          1. 8.5.4.4.1 DIAG_STAT
          2. 8.5.4.4.2 ADC_STAT1
          3. 8.5.4.4.3 ADC_STAT2
          4. 8.5.4.4.4 GPIO_STAT
          5. 8.5.4.4.5 DEV_STAT
        5. 8.5.4.5  ADC Configuration and Control
          1. 8.5.4.5.1  ADC_CONF1
          2. 8.5.4.5.2  ADC_CONF2
          3. 8.5.4.5.3  MAIN_ADC_CAL1
          4. 8.5.4.5.4  MAIN_ADC_CAL2
          5. 8.5.4.5.5  AUX_ADC_CAL1
          6. 8.5.4.5.6  AUX_ADC_CAL2
          7. 8.5.4.5.7  CS_ADC_CAL1
          8. 8.5.4.5.8  CS_ADC_CAL2
          9. 8.5.4.5.9  ADC_CTRL1
          10. 8.5.4.5.10 ADC_CTRL2
          11. 8.5.4.5.11 ADC_CTRL3
        6. 8.5.4.6  ADC Measurement Results
          1. 8.5.4.6.1  VS16_HI/LO
          2. 8.5.4.6.2  VS15_HI/LO
          3. 8.5.4.6.3  VS14_HI/LO
          4. 8.5.4.6.4  VS13_HI/LO
          5. 8.5.4.6.5  VS12_HI/LO
          6. 8.5.4.6.6  VS11_HI/LO
          7. 8.5.4.6.7  VS10_HI/LO
          8. 8.5.4.6.8  VS9_HI/LO
          9. 8.5.4.6.9  VS8_HI/LO
          10. 8.5.4.6.10 VS7_HI/LO
          11. 8.5.4.6.11 VS6_HI/LO
          12. 8.5.4.6.12 VS5_HI/LO
          13. 8.5.4.6.13 VS4_HI/LO
          14. 8.5.4.6.14 VS3_HI/LO
          15. 8.5.4.6.15 VS2_HI/LO
          16. 8.5.4.6.16 VS1_HI/LO
          17. 8.5.4.6.17 CSAUX_HI/LO
          18. 8.5.4.6.18 TSREF_HI/LO
          19. 8.5.4.6.19 GPIO1_HI/LO
          20. 8.5.4.6.20 GPIO2_HI/LO
          21. 8.5.4.6.21 GPIO3_HI/LO
          22. 8.5.4.6.22 GPIO4_HI/LO
          23. 8.5.4.6.23 GPIO5_HI/LO
          24. 8.5.4.6.24 GPIO6_HI/LO
          25. 8.5.4.6.25 GPIO7_HI/LO
          26. 8.5.4.6.26 GPIO8_HI/LO
          27. 8.5.4.6.27 DIETEMP1_HI/LO
          28. 8.5.4.6.28 DIETEMP2_HI/LO
          29. 8.5.4.6.29 AUX_IN_HI/LO
          30. 8.5.4.6.30 AUX_GPIO_HI/LO
          31. 8.5.4.6.31 AUX_PWR_HI/LO
          32. 8.5.4.6.32 AUX_REFL_HI/LO
          33. 8.5.4.6.33 AUX_VBG2_HI/LO
          34. 8.5.4.6.34 AUX_AVAO_REF_HI/LO
          35. 8.5.4.6.35 AUX_AVDD_REF_HI/LO
          36. 8.5.4.6.36 AUX_OV_DAC_HI/LO
          37. 8.5.4.6.37 AUX_UV_DAC_HI/LO
          38. 8.5.4.6.38 AUX_VCM1_HI/LO
          39. 8.5.4.6.39 REFH_HI/LO
          40. 8.5.4.6.40 DIAG_MAIN_HI/LO
          41. 8.5.4.6.41 DIAG_AUX_HI/LO
          42. 8.5.4.6.42 CURRENT_HI/MID/LO
        7. 8.5.4.7  Protector Configuration and Control
          1. 8.5.4.7.1 OV_THRESH
          2. 8.5.4.7.2 UV_THRESH
          3. 8.5.4.7.3 UV_DISABLE1
          4. 8.5.4.7.4 UV_DISABLE2
          5. 8.5.4.7.5 OVUV_CTRL
        8. 8.5.4.8  GPIO Configuration
          1. 8.5.4.8.1 GPIO_CONF1
          2. 8.5.4.8.2 GPIO_CONF2
          3. 8.5.4.8.3 GPIO_CONF3
          4. 8.5.4.8.4 GPIO_CONF4
        9. 8.5.4.9  SPI Master
          1. 8.5.4.9.1 SPI_CONF
          2. 8.5.4.9.2 SPI_EXE
          3. 8.5.4.9.3 SPI_TX3, SPI_TX2, and SPI_TX1
          4. 8.5.4.9.4 SPI_RX3, SPI_RX2, and SPI_RX1
        10. 8.5.4.10 Diagnostic Control
          1. 8.5.4.10.1 DIAG_OTP_CTRL
          2. 8.5.4.10.2 DIAG_COMM_CTRL
          3. 8.5.4.10.3 DIAG_PWR_CTRL
          4. 8.5.4.10.4 DIAG_COMP_CTRL1
          5. 8.5.4.10.5 DIAG_COMP_CTRL2
          6. 8.5.4.10.6 DIAG_COMP_CTRL3
          7. 8.5.4.10.7 DIAG_COMP_CTRL4
          8. 8.5.4.10.8 DIAG_PROT_CTRL
        11. 8.5.4.11 Fault Configuration and Reset
          1. 8.5.4.11.1 FAULT_MSK1
          2. 8.5.4.11.2 FAULT_MSK2
          3. 8.5.4.11.3 FAULT_RST1
          4. 8.5.4.11.4 FAULT_RST2
        12. 8.5.4.12 Fault Status
          1. 8.5.4.12.1  FAULT_SUMMARY
          2. 8.5.4.12.2  FAULT_COMM1
          3. 8.5.4.12.3  FAULT_COMM2
          4. 8.5.4.12.4  FAULT_COMM3
          5. 8.5.4.12.5  FAULT_OTP
          6. 8.5.4.12.6  FAULT_SYS
          7. 8.5.4.12.7  FAULT_PROT1
          8. 8.5.4.12.8  FAULT_PROT2
          9. 8.5.4.12.9  FAULT_OV1
          10. 8.5.4.12.10 FAULT_OV2
          11. 8.5.4.12.11 FAULT_UV1
          12. 8.5.4.12.12 FAULT_UV2
          13. 8.5.4.12.13 FAULT_COMP_GPIO
          14. 8.5.4.12.14 FAULT_COMP_VSAUX1
          15. 8.5.4.12.15 FAULT_COMP_VSAUX2
          16. 8.5.4.12.16 FAULT_COMP_VSOW1
          17. 8.5.4.12.17 FAULT_COMP_VSOW2
          18. 8.5.4.12.18 FAULT_COMP_AUXOW1
          19. 8.5.4.12.19 FAULT_COMP_AUXOW2
          20. 8.5.4.12.20 FAULT_COMP_MISC
          21. 8.5.4.12.21 FAULT_PWR1
          22. 8.5.4.12.22 FAULT_PWR2
          23. 8.5.4.12.23 FAULT_PWR3
        13. 8.5.4.13 Debug Control and Status
          1. 8.5.4.13.1  DEBUG_CTRL_UNLOCK
          2. 8.5.4.13.2  DEBUG_COMM_CTRL1
          3. 8.5.4.13.3  DEBUG_COMM_CTRL2
          4. 8.5.4.13.4  DEBUG_COMM_STAT
          5. 8.5.4.13.5  DEBUG_UART_RC
          6. 8.5.4.13.6  DEBUG_UART_RR_TR
          7. 8.5.4.13.7  DEBUG_COMH_BIT
          8. 8.5.4.13.8  DEBUG_COMH_RC
          9. 8.5.4.13.9  DEBUG_COMH_RR_TR
          10. 8.5.4.13.10 DEBUG_COML_BIT
          11. 8.5.4.13.11 DEBUG_COML_RC
          12. 8.5.4.13.12 DEBUG_COML_RR_TR
          13. 8.5.4.13.13 DEBUG_UART_DISCARD
          14. 8.5.4.13.14 DEBUG_COMH_DISCARD
          15. 8.5.4.13.15 DEBUG_COML_DISCARD
          16. 8.5.4.13.16 DEBUG_UART_VALID_HI/LO
          17. 8.5.4.13.17 DEBUG_COMH_VALID_HI/LO
          18. 8.5.4.13.18 DEBUG_COML_VALID_HI/LO
          19. 8.5.4.13.19 DEBUG_OTP_SEC_BLK
          20. 8.5.4.13.20 DEBUG_OTP_DED_BLK
        14. 8.5.4.14 OTP Programming Control and Status
          1. 8.5.4.14.1 OTP_PROG_UNLOCK1A through OTP_PROG_UNLOCK1D
          2. 8.5.4.14.2 OTP_PROG_UNLOCK2A through OTP_PROG_UNLOCK2D
          3. 8.5.4.14.3 OTP_PROG_CTRL
          4. 8.5.4.14.4 OTP_ECC_TEST
          5. 8.5.4.14.5 OTP_ECC_DATAIN1 through OTP_ECC_DATAIN9
          6. 8.5.4.14.6 OTP_ECC_DATAOUT1 through OTP_ECC_DATAOUT9
          7. 8.5.4.14.7 OTP_PROG_STAT
          8. 8.5.4.14.8 OTP_CUST1_STAT
          9. 8.5.4.14.9 OTP_CUST2_STAT
  10. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Base Device Application Circuit
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1  PACK+ and FUSE Measurement
          2. 9.2.1.2.2  Insulation Measurement
          3. 9.2.1.2.3  LINK+/- Measurement
          4. 9.2.1.2.4  CHARGE+/– Measurement
          5. 9.2.1.2.5  Overcurrent Detection Scheme Using OVUV Comparators
          6. 9.2.1.2.6  Unused Pins
          7. 9.2.1.2.7  Current Sense Input
          8. 9.2.1.2.8  VPWR and External NPN
          9. 9.2.1.2.9  Power Supplies, Reference Input
          10. 9.2.1.2.10 GPIO For Thermistor Inputs
          11. 9.2.1.2.11 UART, NFAULT
          12. 9.2.1.2.12 Daisy-Chain Isolation
            1. 9.2.1.2.12.1 Devices Connected on the Same PCB
            2. 9.2.1.2.12.2 Devices Connected on Different PCBs
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Daisy Device Application Circuit
  11. 10Power Supply Recommendations
  12. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Ground Planes
      2. 11.1.2 Bypass Capacitors for Power Supplies and Reference
      3. 11.1.3 Voltage Sensing
      4. 11.1.4 Daisy-Chain Communication
    2. 11.2 Layout Example
  13. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 第三方产品免责声明
    2. 12.2 接收文档更新通知
    3. 12.3 支持资源
    4. 12.4 Trademarks
    5. 12.5 静电放电警告
    6. 12.6 术语表
  14. 13Mechanical, Packaging, and Orderable Information

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息
VS Voltage Measurement Check

VS voltage measurement path comparison:

The VS voltage measurement check is performed by comparing the prefiltered measurement result from Main ADC versus measurement result from AUX ADC. To read the compared value measured by Main ADC and AUX ADC, MCU has to set up this diagnostic check to lock on a single channel using [AUX_IN_SEL] setting and the start this diagnostic check. In this configuration, the compared values from Main ADC and AUX ADC are reported to DIAG_MAIN_HI/LO registers and DIAG_AUX_HI/LO registers respectively.

Both Main and AUX ADC has the same front end filters. This diagnostic time is mostly spend on waiting for the AAF on the AUX ADC path to settle. The [AUX_SETTLE] setting allows the MCU to make trade-off between diagnostic time and noise filter level. Additionally, when AUX ADC starts, by default, AUX slot always align to the Main ADC VS1 slot. The [AUX_IN_ALIGN] setting allows MCU to change this alignment to Main ADC VS8 slot, resulting with less sampling time delta between Main and AUX ADC on the higher channels. The device does not do on-chip measurement check for SRP/SRN signal.

GUID-20210809-SS0I-TLDS-0MCN-CKPBNKC5BGHG-low.svg Figure 8-40 VS Voltage Measurement Diagnostic

Before starting the voltage measurement comparison between VS and AUX, host ensures:

  • The desired AUX channels to be tested are configured in the ADC_CTRL2[AUX_IN_SEL4:0] setting and AUX ADC is enabled and in continuous mode.
  • Allow AUX ADC to run through all AUX channels for the devie to compensate for common mode error before starting this diagnostic check.
  • Main ADC must be enabled and is in continuous mode.
  • Select the (VS – AUX) comparison threshold through DIAG_COMP_CTRL1[VSAUX4:0] setting.
  • Select the desired settling time for the AUX channel through ADC_CONF1[AUX_SETTLE1:0].

To start the VS and AUX voltage measurement comparison:

  1. Set DIAG_COMP_CTRL3[COMP_ADC_SEL2:0] = VS voltage measurement check (that is, 0b001) and set [COMP_ADC_GO] = 1.
  2. For each channel enabled by [AUX_IN_SEL4:0], the device will compare abs[(VS – AUX)] < [VSAUX4:0].
  3. Wait for the comparison to be accomplished, roughly [(number of channel) * (AUX settling time + one round robin cycle time)].
  4. The input voltage measurement comparison is completed when ADC_STAT2[DRDY_VSAUX] = 1.

Host checks the FAULT_COMP_VSAUX1 and FAULT_COMP_VSAUX2 registers for the comparison result.

ADC comparison abort conditions:

The device will not start the VS voltage measurement comparison under the invalid conditions listed below. When the comparison is aborted, the FAULT_COMP_MISC[COMP_ADC_ABORT] = 1, [DRDY_AUX_IN] = 1, [DRDY_VSAUX] = 1, and FAULT_COMP_VSAUX1/2 registers = 0xFF. If [AUX_IN_SEL4:0] is set to locked at a single channel, the AUX_IN_HI/LO registers will be reset to default value 0x8000 if the comparison run is aborted.

Invalid conditions or settings which will prevent the start of the VS voltage measurement comparison:

  • Invalid [AUX_IN_SEL] setting: results in no AUX ADC measurement on the selected channel. The AUX_IN_HI/LO registers are kept in default value.
  • Main or AUX ADCs are off or not set in continuous mode.

Post-ADC digital LPF check:

The digital LPF is checked continuous whenever the Main ADC is running. A duplicate diagnostic LPF is implemented to check against each LPF for each VS channel and the CSAUX channel. The check is performed with one LPF at a time.

Example, to test LPF1 for VS1, the input (that is, ADC measurement result from VS1) is fed to the LPF1 and the diagnostic LPF for a period of time. The output of the LPF1 and the diagnostic LPF are compared against each other. Several outputs from LPF1 and diagnostic LPF will be compared to ensure the operation of the LFP1 before moving to check the next LFP. If any of the LPFs fail the diagnostic check, FAULT_COMP_MISC[LPF_FAIL] = 1.

When the LPF for each VS channel is tested once, ADC_STAT2[DRDY_LPF] = 1. This diagnostic check of the LPFs will continuously run in the background as long as the Main ADC is running.

GUID-20210809-SS0I-6ZRF-NBWQ-LGQMHMRQBJGG-low.svg Figure 8-41 Post-ADC LPF Diagnostic (Blue Path as Example of Checking LPF1)

Furthermore, the device also implements a check to verify the functionality of the diagnostic LPF itself. By setting DIAG_COMP_CTRL4[LPF_FAULT_INJ] = 1 and restarting the Main ADC, the device will inject a fault into the diagnostic LPF, forcing a failure during the LPF diagnostic check which then sets the [LPF_FAIL] = 1. When the test is completed, simply set the [LPF_FAULT_INJ] = 0.