SLOSE32A April   2019  – October 2019 TAS6421-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Functional Block Diagram
  4. 4 Revision History
  5. 5 Device Options
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 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 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Serial Audio Port
        1. 9.3.1.1 I2S Mode
        2. 9.3.1.2 Left-Justified Timing
        3. 9.3.1.3 Right-Justified Timing
        4. 9.3.1.4 TDM Mode
        5. 9.3.1.5 Supported Clock Rates
        6. 9.3.1.6 Audio-Clock Error Handling
      2. 9.3.2  DC Blocking
      3. 9.3.3  Volume Control and Gain
      4. 9.3.4  High-Frequency Pulse-Width Modulator (PWM)
      5. 9.3.5  Gate Drive
      6. 9.3.6  Power FETs
      7. 9.3.7  Load Diagnostics
        1. 9.3.7.1 DC Load Diagnostics
        2. 9.3.7.2 Line Output Diagnostics
        3. 9.3.7.3 AC Load Diagnostics
          1. 9.3.7.3.1 Impedance Magnitude Measurement
          2. 9.3.7.3.2 Impedance Phase Reference Measurement
          3. 9.3.7.3.3 Impedance Phase Measurement
      8. 9.3.8  Protection and Monitoring
        1. 9.3.8.1 Overcurrent Limit (ILIMIT)
        2. 9.3.8.2 Overcurrent Shutdown (ISD)
        3. 9.3.8.3 DC Detect
        4. 9.3.8.4 Clip Detect
        5. 9.3.8.5 Global Overtemperature Warning (OTW), Overtemperature Shutdown (OTSD)
        6. 9.3.8.6 Channel Overtemperature Warning [OTW(i)] and Shutdown [OTSD(i)]
        7. 9.3.8.7 Undervoltage (UV) and Power-On-Reset (POR)
        8. 9.3.8.8 Overvoltage (OV) and Load Dump
      9. 9.3.9  Power Supply
        1. 9.3.9.1 Vehicle-Battery Power-Supply Sequence
          1. 9.3.9.1.1 Power-Up Sequence
          2. 9.3.9.1.2 Power-Down Sequence
        2. 9.3.9.2 Boosted Power-Supply Sequence
      10. 9.3.10 Hardware Control Pins
        1. 9.3.10.1 FAULT
        2. 9.3.10.2 WARN
        3. 9.3.10.3 MUTE
        4. 9.3.10.4 STANDBY
    4. 9.4 Device Functional Modes
      1. 9.4.1 Operating Modes and Faults
    5. 9.5 Programming
      1. 9.5.1 I2C Serial Communication Bus
      2. 9.5.2 I2C Bus Protocol
      3. 9.5.3 Random Write
      4. 9.5.4 Sequential Write
      5. 9.5.5 Random Read
      6. 9.5.6 Sequential Read
    6. 9.6 Register Maps
      1. 9.6.1  Mode Control Register (address = 0x00) [default = 0x00]
        1. Table 9. Mode Control Field Descriptions
      2. 9.6.2  Miscellaneous Control 1 Register (address = 0x01) [default = 0x32]
        1. Table 10. Misc Control 1 Field Descriptions
      3. 9.6.3  Miscellaneous Control 2 Register (address = 0x02) [default = 0x62]
        1. Table 11. Misc Control 2 Field Descriptions
      4. 9.6.4  SAP Control (Serial Audio-Port Control) Register (address = 0x03) [default = 0x04]
        1. Table 12. SAP Control Field Descriptions
      5. 9.6.5  Channel State Control Register (address = 0x04) [default = 0x55]
        1. Table 13. Channel State Control Field Descriptions
      6. 9.6.6  Channel 1 Volume Control Register (address = 0x05) [default = 0xCF]
        1. Table 14. Ch 1 Volume Control Field Descriptions
      7. 9.6.7  DC Load Diagnostic Control 1 Register (address = 0x09) [default = 0x00]
        1. Table 15. DC Load Diagnostics Control 1 Field Descriptions
      8. 9.6.8  DC Load Diagnostic Control 2 Register (address = 0x0A) [default = 0x11]
        1. Table 16. DC Load Diagnostics Control 2 Field Descriptions
      9. 9.6.9  DC Load Diagnostic Report 1 Register (address = 0x0C) [default = 0x00]
        1. Table 17. DC Load Diagnostics Report 1 Field Descriptions
      10. 9.6.10 DC Load Diagnostics Report 3 Line Output Register (address = 0x0E) [default = 0x00]
        1. Table 18. DC Load Diagnostics Report 3 Line Output Field Descriptions
      11. 9.6.11 Channel State Reporting Register (address = 0x0F) [default = 0x40]
        1. Table 19. State-Reporting Field Descriptions
      12. 9.6.12 Channel Faults (Overcurrent, DC Detection) Register (address = 0x10) [default = 0x00]
        1. Table 20. Channel Faults Field Descriptions
      13. 9.6.13 Global Faults 1 Register (address = 0x11) [default = 0x00]
        1. Table 21. Global Faults 1 Field Descriptions
      14. 9.6.14 Global Faults 2 Register (address = 0x12) [default = 0x00]
        1. Table 22. Global Faults 2 Field Descriptions
      15. 9.6.15 Warnings Register (address = 0x13) [default = 0x20]
        1. Table 23. Warnings Field Descriptions
      16. 9.6.16 Pin Control Register (address = 0x14) [default = 0x00]
        1. Table 24. Pin Control Field Descriptions
      17. 9.6.17 AC Load Diagnostic Control 1 Register (address = 0x15) [default = 0x00]
        1. Table 25. AC Load Diagnostic Control 1 Field Descriptions
      18. 9.6.18 AC Load Diagnostic Control 2 Register (address = 0x16) [default = 0x00]
        1. Table 26. AC Load Diagnostic Control 2 Field Descriptions
      19. 9.6.19 AC Load Diagnostic Impedance Report Ch1 Register (address = 0x17) [default = 0x00]
        1. Table 27. Ch1 AC LDG Impedance Report Field Descriptions
      20. 9.6.20 AC Load Diagnostic Phase Report High Register (address = 0x1B) [default = 0x00]
        1. Table 28. AC LDG Phase High Report Field Descriptions
      21. 9.6.21 AC Load Diagnostic Phase Report Low Register (address = 0x1C) [default = 0x00]
        1. Table 29. AC LDG Phase Low Report Field Descriptions
      22. 9.6.22 AC Load Diagnostic STI Report High Register (address = 0x1D) [default = 0x00]
        1. Table 30. AC LDG STI High Report Field Descriptions
      23. 9.6.23 AC Load Diagnostic STI Report Low Register (address = 0x1E) [default = 0x00]
        1. Table 31. Ch1 AC LDG STI Low Report Field Descriptions
      24. 9.6.24 Miscellaneous Control 3 Register (address = 0x21) [default = 0x00]
        1. Table 32. Misc Control 3 Field Descriptions
      25. 9.6.25 Clip Control Register (address = 0x22) [default = 0x01]
        1. Table 33. Clip Control Field Descriptions
      26. 9.6.26 Clip Window Register (address = 0x23) [default = 0x14]
        1. Table 34. Clip Window Field Descriptions
      27. 9.6.27 Clip Warning Register (address = 0x24) [default = 0x00]
        1. Table 35. Clip Warning Field Descriptions
      28. 9.6.28 ILIMIT Status Register (address = 0x25) [default = 0x00]
        1. Table 36. ILIMIT Status Field Descriptions
      29. 9.6.29 Miscellaneous Control 4 Register (address = 0x26) [default = 0x40]
        1. Table 37. Misc Control 4 Field Descriptions
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 AM-Radio Band Avoidance
      2. 10.1.2 Demodulation Filter Design
      3. 10.1.3 Line Driver Applications
    2. 10.2 Typical Applications
      1. 10.2.1 BTL Application
        1. 10.2.1.1 Design Requirements
          1. 10.2.1.1.1 Communication
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1 Hardware Design
          2. 10.2.1.2.2 Digital Input and the Serial Audio Port
          3. 10.2.1.2.3 Bootstrap Capacitors
          4. 10.2.1.2.4 Output Reconstruction Filter
      2. 10.2.2 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Electrical Connection of Thermal pad and Heat Sink
      2. 12.1.2 EMI Considerations
      3. 12.1.3 General Guidelines
    2. 12.2 Layout Example
    3. 12.3 Thermal Considerations
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Community Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary

Package Options

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

10.2.1.2.4 Output Reconstruction Filter

The output FETs drive the amplifier outputs in an H-Bridge configuration. These transistors are either fully off or fully on. The result is a square-wave output signal with a duty cycle that is proportional to the amplitude of the audio signal. The amplifier outputs require a reconstruction filter that comprises a series inductor and a capacitor to ground on each output, generally called an LC filter. The LC filter attenuates the PWM frequency and reduces electromagnetic emissions, allowing the reconstructed audio signal to pass to the speakers. Refer to the Class-D LC Filter Design Application Report for a detailed description of proper component description and design of the LC filter based upon the specified load and frequency response. The recommended low-pass cutoff frequency of the LC filter is dependent on the selected switching frequency. The low-pass cutoff frequency can be as high as 100 kHz for a PWM frequency of 2.1 MHz. At a PWM frequency of 384 kHz the low-pass cutoff frequency should be less than 40 kHz. Certain specifications must be understood for a proper inductor. The inductance value is given at zero current, but the TAS6421-Q1 device has current. Use the inductance versus current curve for the inductor to make sure the inductance does not drop below 1 µH (for fSW = 2.1 MHz) at the maximum current provided by the system design. The DCR of the inductor directly affects the output power of the system design. The lower the DCR, the more power is provided to the speakers. The typical inductor DCR for a 4 Ω system is 40 to 50 mΩ and for a 2 Ω system is 20 to 25 mΩ. Further guidance is provided in the Inductor Selection Guide for 2.1 MHz Class-D Amplifiers.