SLASEP6B September   2019  – December 2020 TPA6304-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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 Typical Characteristics
      1. 6.6.1 Bridge-Tied Load (BTL), BD
      2. 6.6.2 Parallel Bridge-Tied Load (PBTL)
      3. 6.6.3 Bridge-Tied Load (BTL), 1SPW
      4. 6.6.4 Bridge-Tied Load (BTL), 384 kHz, BD
      5. 6.6.5 Bridge-Tied Load (BTL), 384 kHz, 1SPW
  7. 7 Parameter measurement information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Single-Ended Analog Inputs
      2. 7.3.2  Gain Control
      3. 7.3.3  Class-D Operation and Spread Spectrum Control
        1. 7.3.3.1 High Frequency Pulse Width Modulator (PWM)
        2. 7.3.3.2 Clock Synchronization
        3. 7.3.3.3 Spread Spectrum Control
      4. 7.3.4  Gate Drive
      5. 7.3.5  Power FETs
      6. 7.3.6  Load Diagnostics
        1. 7.3.6.1 DC Load Diagnostics
          1. 7.3.6.1.1 Automatic DC Load Diagnostics at Device Initialization
          2. 7.3.6.1.2 Automatic DC Load Diagnostics During Hi-Z to MUTE or PLAY Transition
          3. 7.3.6.1.3 Manual Start of DC Load Diagnostics
          4. 7.3.6.1.4 Short-to-Ground
          5. 7.3.6.1.5 Short-to-Power
          6. 7.3.6.1.6 Shorted Load and Open Load
          7. 7.3.6.1.7 Line Output Diagnostics
        2. 7.3.6.2 AC Load Diagnostics
          1. 7.3.6.2.1 Operating Principal
          2. 7.3.6.2.2 Stimulus
          3. 7.3.6.2.3 Load Impedance
          4. 7.3.6.2.4 Tweeter Detection
          5. 7.3.6.2.5 Operation
      7. 7.3.7  Power Supply
        1. 7.3.7.1 Power-Supply Sequence
          1. 7.3.7.1.1 Power-Up Sequence
          2. 7.3.7.1.2 Power-Down Sequence
      8. 7.3.8  Device Initialization and Power-On-Reset (POR)
      9. 7.3.9  Protection and Monitoring
        1. 7.3.9.1 Over Current Protection
        2. 7.3.9.2 DC Detect
        3. 7.3.9.3 Load Current Limit
        4. 7.3.9.4 Clip Detect
        5. 7.3.9.5 Temperature Protection and Monitoring
          1. 7.3.9.5.1 Over Temperature Shutdown (OTSD)
          2. 7.3.9.5.2 Over Temperature Warning (OTW)
          3. 7.3.9.5.3 Thermal Gain Foldback (TGFB)
        6. 7.3.9.6 Power Failures
        7. 7.3.9.7 Load Dump Protection
      10. 7.3.10 Hardware Control Pins
        1. 7.3.10.1 FAULT Pin
        2. 7.3.10.2 STANDBY Pin
        3. 7.3.10.3 GPIO Pins
        4. 7.3.10.4 WARNING
        5. 7.3.10.5 MUTE
    4. 7.4 Device Functional Modes
      1. 7.4.1 Internal Reporting Signals
        1. 7.4.1.1 Fault Signal
        2. 7.4.1.2 Warning Signal
        3. 7.4.1.3 Clip Detect Signal
      2. 7.4.2 Device States and Flags
        1. 7.4.2.1 Audio Channel States
          1. 7.4.2.1.1 PROTECTIVE SHUTDOWN with AUTO RECOVERY State
          2. 7.4.2.1.2 PROTECTIVE SHUTDOWN State
            1. 7.4.2.1.2.1 Clear Fault
        2. 7.4.2.2 Status and Memory Registers
          1. 7.4.2.2.1 Status Registers
          2. 7.4.2.2.2 Memory Registers
      3. 7.4.3 Fault Events
        1. 7.4.3.1 Overview
        2. 7.4.3.2 Power Fault Events
          1. 7.4.3.2.1 DVDD POR
          2. 7.4.3.2.2 VBAT Over Voltage Fault
          3. 7.4.3.2.3 VBAT Under Voltage Fault
          4. 7.4.3.2.4 PVDD Over Voltage Fault
          5. 7.4.3.2.5 PVDD Under Voltage Fault
          6. 7.4.3.2.6 GVDD Fault
        3. 7.4.3.3 Over Temperature Shut Down (OTSD) Event
        4. 7.4.3.4 Over Current Shut Down (OCSD) Event
        5. 7.4.3.5 DC Fault Event
        6. 7.4.3.6 Load Current Fault Event
        7. 7.4.3.7 Invalid Clock Fault Event
      4. 7.4.4 Warning Events
        1. 7.4.4.1 Overview
        2. 7.4.4.2 Over Temperature Warning Event
        3. 7.4.4.3 Thermal Gain Foldback Warning Event
        4. 7.4.4.4 Load Current Warning Event
        5. 7.4.4.5 Clip Warning Event
    5. 7.5 Programming
      1. 7.5.1 I2C Serial Communication Bus
        1. 7.5.1.1 I2C Address Selection
      2. 7.5.2 I2C Bus Protocol
        1. 7.5.2.1 Random Write
        2. 7.5.2.2 Sequential Write
        3. 7.5.2.3 Random Read
        4. 7.5.2.4 Sequential Read
    6. 7.6 Register Maps
      1. 7.6.1 Registers
  9. 8 Application Information Disclaimer
    1. 8.1 Application Information
      1. 8.1.1 AM Radio Avoidance
      2. 8.1.2 Parallel BTL Operation (PBTL)
      3. 8.1.3 Reconstruction Filter Design
      4. 8.1.4 Bootstrap Capacitors
      5. 8.1.5 Line Driver Applications
    2. 8.2 Typical Applications
      1. 8.2.1 BTL Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Hardware Design Procedure
      2. 8.2.2 PBTL Application
        1. 8.2.2.1 Detailed Hardware Design Procedure
  10. 9 Power Supply Recommendations
  11. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Electrical Connection of Thermal Pad and Heat Sink
      2. 10.1.2 General Considerations
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
  12. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary

Package Options

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

8.1.3 Reconstruction Filter Design

The amplifier outputs are driven by high-current LDMOS transistors 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 half-bridge 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. Design of the reconstruction filter significantly affects the audio performance of the power amplifier. Therefore, to meet the system THD+N requirements, the selection of the inductors used in the output filter should be carefully considered. Refer to the Class-D LC Filter Design, SLAA701A, 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.

Certain specifications must be understood for a proper inductor. See the application note TAS6424-Q1 Inductor Selection Guide, SLOA242, for information on selection the proper inductor. The inductance value is given at zero current, but the inductors do have current through them as the TPA6304-Q1 drives current into the load. Use the inductance versus current curve for the inductor to made sure the inductance does not drop below 2 µH (for fsw = 2.1 MHz) at the maximum current for the system design during normal operation. 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 15 to 25 mΩ.