SLOS948 February   2019 TAS6424M-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     PCB AREA
  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 Timing Requirements
    7. 7.7 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  High-Pass Filter
      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
        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 10. Mode Control Field Descriptions
      2. 9.6.2  Miscellaneous Control 1 Register (address = 0x01) [default = 0x32]
        1. Table 11. Misc Control 1 Field Descriptions
      3. 9.6.3  Miscellaneous Control 2 Register (address = 0x02) [default = 0x62]
        1. Table 12. Misc Control 2 Field Descriptions
      4. 9.6.4  SAP Control (Serial Audio-Port Control) Register (address = 0x03) [default = 0x04]
        1. Table 13. SAP Control Field Descriptions
      5. 9.6.5  Channel State Control Register (address = 0x04) [default = 0x55]
        1. Table 14. Channel State Control Field Descriptions
      6. 9.6.6  Channel 1 Through 4 Volume Control Registers (address = 0x05–0x08) [default = 0xCF]
        1. Table 15. Ch x Volume Control Field Descriptions
      7. 9.6.7  DC Load Diagnostic Control 1 Register (address = 0x09) [default = 0x00]
        1. Table 16. DC Load Diagnostics Control 1 Field Descriptions
      8. 9.6.8  DC Load Diagnostic Control 2 Register (address = 0x0A) [default = 0x11]
        1. Table 17. DC Load Diagnostics Control 2 Field Descriptions
      9. 9.6.9  DC Load Diagnostic Control 3 Register (address = 0x0B) [default = 0x11]
        1. Table 18. DC Load Diagnostics Control 3 Field Descriptions
      10. 9.6.10 DC Load Diagnostic Report 1 Register (address = 0x0C) [default = 0x00]
        1. Table 19. DC Load Diagnostics Report 1 Field Descriptions
      11. 9.6.11 DC Load Diagnostic Report 2 Register (address = 0x0D) [default = 0x00]
        1. Table 20. DC Load Diagnostics Report 2 Field Descriptions
      12. 9.6.12 DC Load Diagnostics Report 3 Line Output Register (address = 0x0E) [default = 0x00]
        1. Table 21. DC Load Diagnostics Report 3 Line Output Field Descriptions
      13. 9.6.13 Channel State Reporting Register (address = 0x0F) [default = 0x55]
        1. Table 22. State-Reporting Field Descriptions
      14. 9.6.14 Channel Faults (Overcurrent, DC Detection) Register (address = 0x10) [default = 0x00]
        1. Table 23. Channel Faults Field Descriptions
      15. 9.6.15 Global Faults 1 Register (address = 0x11) [default = 0x00]
        1. Table 24. Global Faults 1 Field Descriptions
      16. 9.6.16 Global Faults 2 Register (address = 0x12) [default = 0x00]
        1. Table 25. Global Faults 2 Field Descriptions
      17. 9.6.17 Warnings Register (address = 0x13) [default = 0x20]
        1. Table 26. Warnings Field Descriptions
      18. 9.6.18 Pin Control Register (address = 0x14) [default = 0x00]
        1. Table 27. Pin Control Field Descriptions
      19. 9.6.19 AC Load Diagnostic Control 1 Register (address = 0x15) [default = 0x00]
        1. Table 28. AC Load Diagnostic Control 1 Field Descriptions
      20. 9.6.20 AC Load Diagnostic Control 2 Register (address = 0x16) [default = 0x00]
        1. Table 29. AC Load Diagnostic Control 2 Field Descriptions
      21. 9.6.21 AC Load Diagnostic Impedance Report Ch1 through CH4 Registers (address = 0x17–0x1A) [default = 0x00]
        1. Table 30. Chx AC LDG Impedance Report Field Descriptions
      22. 9.6.22 AC Load Diagnostic Phase Report High Register (address = 0x1B) [default = 0x00]
        1. Table 31. AC LDG Phase High Report Field Descriptions
      23. 9.6.23 AC Load Diagnostic Phase Report Low Register (address = 0x1C) [default = 0x00]
        1. Table 32. AC LDG Phase Low Report Field Descriptions
      24. 9.6.24 AC Load Diagnostic STI Report High Register (address = 0x1D) [default = 0x00]
        1. Table 33. AC LDG STI High Report Field Descriptions
      25. 9.6.25 AC Load Diagnostic STI Report Low Register (address = 0x1E) [default = 0x00]
        1. Table 34. Chx AC LDG STI Low Report Field Descriptions
      26. 9.6.26 Miscellaneous Control 3 Register (address = 0x21) [default = 0x00]
        1. Table 35. Misc Control 3 Field Descriptions
      27. 9.6.27 Clip Control Register (address = 0x22) [default = 0x01]
        1. Table 36. Clip Control Field Descriptions
      28. 9.6.28 Clip Window Register (address = 0x23) [default = 0x14]
        1. Table 37. Clip Window Field Descriptions
      29. 9.6.29 Clip Warning Register (address = 0x24) [default = 0x00]
        1. Table 38. Clip Warning Field Descriptions
      30. 9.6.30 ILIMIT Status Register (address = 0x25) [default = 0x00]
        1. Table 39. ILIMIT Status Field Descriptions
      31. 9.6.31 Miscellaneous Control 4 Register (address = 0x26) [default = 0x40]
        1. Table 40. 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 Parallel BTL Operation (PBTL)
      3. 10.1.3 Demodulation Filter Design
      4. 10.1.4 Line Driver Applications
    2. 10.2 Typical Applications
      1. 10.2.1 BTL Application
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Communication
        3. 10.2.1.3 Detailed Design Procedure
          1. 10.2.1.3.1 Hardware Design
          2. 10.2.1.3.2 Digital Input and the Serial Audio Port
          3. 10.2.1.3.3 Bootstrap Capacitors
          4. 10.2.1.3.4 Output Reconstruction Filter
        4. 10.2.1.4 Application Curves
      2. 10.2.2 PBTL Application
        1. 10.2.2.1 Design Requirements
          1. 10.2.2.1.1 Detailed Design Procedure
        2. 10.2.2.2 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
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

10.2.1.3.4 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, (SLOA119) 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 TAS6424M-Q1 device will have 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.