SLAAED9 November   2023 TAA5412-Q1 , TAC5311-Q1 , TAC5312-Q1 , TAC5411-Q1 , TAC5412-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Introduction
  5. 2 Diagnostic Monitoring Architecture
  6. 3 Monitored Faults
    1. 3.1 Microphone Faults
      1. 3.1.1 Inputs Shorted to Ground
      2. 3.1.2 Inputs Shorted to MICBIAS
      3. 3.1.3 Input Open Circuit
      4. 3.1.4 Input Pins Shorted Together
      5. 3.1.5 Input Overvoltage Detection
      6. 3.1.6 Inputs Shorted to VBAT
    2. 3.2 Line Out Faults
      1. 3.2.1 Output Overcurrent
      2. 3.2.2 Virtual Ground
    3. 3.3 Other Faults
      1. 3.3.1 MICBIAS Overvoltage
        1. 3.3.1.1 DIAG_CFG11 Register (page = 0x01, address = 0x51) [Reset = 0x40]
      2. 3.3.2 MICBIAS Overcurrent
      3. 3.3.3 MICBIAS Load Current
        1. 3.3.3.1 DIAG_CFG6 Register (page = 0x01, address = 0x4C) [Reset = 0xA2]
        2. 3.3.3.2 DIAG_CFG7 Register
      4. 3.3.4 Overtemperature Fault
      5. 3.3.5 Supply Back Pumping
  7. 4 Enabling Diagnostics and Programming Thresholds
    1. 4.1 DIAG_CFG0 Register (page = 0x01, Address = 0x46) [Reset = 0x00]
    2. 4.2 DIAG_CFG1 Register (page = 0x01, Address = 0x47) [Reset = 0x37]
    3. 4.3 DIAG_CFG2 Register (page = 0x01, Address = 0x48) [Reset = 0x87]
  8. 5 Fault Diagnostic Setup Procedure
  9. 6 Fault Reporting
    1. 6.1 Live Registers
      1. 6.1.1 CHx_LIVE Register (page = 0x01, address = 0x3D) [Reset = 0b]
      2. 6.1.2 CH1_LIVE Register (page = 0x01, address = 0x3E) [Reset = 0h]
      3. 6.1.3 INT_LIVE0 Register (page = 0x01, address = 0x3C) [Reset = 00]
      4. 6.1.4 INT_LIVE1 Register (page = 0x00, address = 0x42) [reset = 0x00]
      5. 6.1.5 INT_LIVE2 Register (page = 0x00, address = 0x43) [reset = 0x00]
    2. 6.2 Latched Registers
      1. 6.2.1 Clearing Latched Registers
    3. 6.3 Fault Filtering and Response Time
      1. 6.3.1 Debounce
      2. 6.3.2 Scan Rate
        1. 6.3.2.1 DIAG_CFG4 Register (page = 0x01, address = 0x4A) [reset = 0xB8]
      3. 6.3.3 Moving Average
        1. 6.3.3.1 DIAG_CFG5 Register (page = 0x01, address = 0x4B) [reset = 0h]
  10. 7 Responding to a Fault
    1. 7.1 INT_CFG Register (page = 0x00, address = 0x42) [reset = 0b]
      1. 7.1.1 DIAG_CFG10 Register (page = 0x01, address = 0x50) [Reset = 0x88]
    2. 7.2 Manual Recovery Sequence
    3. 7.3 Recommended Fault Register Read Sequence
  11. 8 Using PurePath Console
    1. 8.1 Advanced Tab
    2. 8.2 Diagnostics Walk-through
      1. 8.2.1 Diagnostics Configuration
      2. 8.2.2 Debounce Configuration
      3. 8.2.3 Latched Fault Status
  12. 9 Diagnostic Monitoring Registers
    1. 9.1 Voltage Measurements
    2. 9.2 MICBIAS Load Current
    3. 9.3 Internal Die Temperature
  13. 10Summary
  14. 11References

3.3.5 Supply Back Pumping

Due to the complex nature of circuits within automotive systems, connections can easily be shorted to one another, jeopardizing the integrity of audio system. As an example, the MICBIAS pin can potentially short to the primary battery supply, VBAT, and drive the MICBIAS to a higher voltage thus unintentionally pumping current back through the MICBIAS pin. A traditional MICBIAS does not have the ability to synchronize current if unintentionally shorted to another power supply source, so this hazard induces a reliability issue in the system. The TAx5x1x-Q1 integrates important protective features within the audio device to prevent back-pumping from damaging the integrity of the device.

As shown in Figure 3-10, the MICBIAS pin monitors any variations in the bias voltage and has integrated circuitry to synchronize current with a higher voltage in the case of back-pumping. Back-pumping or a sudden change in the power supply voltage (for example, a voltage spike or dip) can propagate through the MICBIAS pin, boost, HVDD, and the microphone. These pins are protected from reverse current and a short to a voltage higher than the programmed maximum threshold to provide a stable bias voltage for the microphone and a clean power supply for TAx5xxx-Q1.

GUID-20231108-SS0I-PV9F-NSNF-KDB5DGMDNJGZ-low.svgFigure 3-10 Supply Back Pumping Diagram