SLOS882B January   2015  – December 2017 TPA3140D2

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Device Comparison Table
  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 Switching Characteristics
    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  Gain Setting via GAIN Pin
      2. 9.3.2  SD Operation
      3. 9.3.3  Gain Limit Control, LIMTHRES and LIMRATE
      4. 9.3.4  SPEAKERGUARD Automatic Gain Limit, AGL
      5. 9.3.5  Thermal Foldback, TFB
      6. 9.3.6  PLIMIT
      7. 9.3.7  LIMTHRES
      8. 9.3.8  Spread Spectrum and De-Phase Control
      9. 9.3.9  GVDD Supply
      10. 9.3.10 DC Detect
      11. 9.3.11 PBTL Select
      12. 9.3.12 Short-Circuit Protection and Automatic Recovery Feature
      13. 9.3.13 Thermal Protection
    4. 9.4 Device Functional Modes
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Design Requirements
        1. 10.2.1.1 PCB Material Recommendation
        2. 10.2.1.2 PVCC Capacitor Recommendation
        3. 10.2.1.3 Decoupling Capacitor Recommendations
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Ferrite Bead Filter Considerations
        2. 10.2.2.2 Efficiency: LC Filter Required with the Traditional Class-D Modulation Scheme
        3. 10.2.2.3 When to Use an Output Filter for EMI Suppression
        4. 10.2.2.4 Input Resistance
        5. 10.2.2.5 Input Capacitor, Ci
        6. 10.2.2.6 BSN and BSP Capacitors
        7. 10.2.2.7 Differential Inputs
        8. 10.2.2.8 Using Low-ESR Capacitors
      3. 10.2.3 Application Performance Curves
        1. 10.2.3.1 EN55013 Radiated Emissions Results
        2. 10.2.3.2 EN55022 Conducted Emissions Results
  11. 11Power Supply Recommendations
    1. 11.1 Power Supply Decoupling, CS
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    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

9.4 Device Functional Modes

The TPA3140D2 has the option of running in either BD modulation or 1SPW modulation; this is set by the 1SPW pin.

1SPW = GND: BD-modulation

This is a modulation scheme that allows operation without the classic LC reconstruction filter when the amp is driving an inductive load with short speaker wires. Each output is switching from 0 volts to the supply voltage. The OUTPx and OUTNx are in phase with each other with no input so that there is little or no current in the speaker. The duty cycle of OUTPx is greater than 50% and OUTNx is less than 50% for positive output voltages. The duty cycle of OUTPx is less than 50% and OUTNx is greater than 50% for negative output voltages. The voltage across the load sits at 0V throughout most of the switching period, reducing the switching current, which reduces any I2R losses in the load.

TPA3140D2 BD_mode_modulation_los708.gifFigure 23. BD Mode Modulation

1SPW = HIGH: 1SPW-modulation

The 1SPW mode alters the normal modulation scheme in order to achieve higher efficiency with a slight penalty in THD degradation and more attention required in the output filter selection. In 1SPW mode the outputs operate at ~15% modulation during idle conditions. When an audio signal is applied one output will decrease and one will increase. The decreasing output signal will quickly rail to GND at which point all the audio modulation takes place through the rising output. The result is that only one output is switching during a majority of the audio cycle. Efficiency is improved in this mode due to the reduction of switching losses. The THD penalty in 1SPW mode is minimized by the high performance feedback loop. The resulting audio signal at each half output has a discontinuity each time the output rails to GND. This can cause ringing in the audio reconstruction filter unless care is taken in the selection of the filter components and type of filter used.

TPA3140D2 1SPW_mode_modulation_los708.gifFigure 24. 1SPW Mode Modulation