SLOS638C November   2011  – June 2022 TPA2015D1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and 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 Operating 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 SpeakerGuard™ Theory of Operation
        1. 9.3.1.1 SpeakerGuard™ With Varying Input Levels
        2. 9.3.1.2 Battery Tracking SpeakerGuard™
      2. 9.3.2 Fully Differential Class-D Amplifier
        1. 9.3.2.1 Advantages of Fully Differential Amplifiers
        2. 9.3.2.2 Improved Class-D Efficiency
      3. 9.3.3 Adaptive Boost Converter
        1. 9.3.3.1 Boost Converter Overvoltage Protection
      4. 9.3.4 Operation With DACs and CODECs
      5. 9.3.5 Filter Free Operation and Ferrite Bead Filters
      6. 9.3.6 Speaker Load Limitation
      7. 9.3.7 Fixed Gain Setting
    4. 9.4 Device Functional Modes
      1. 9.4.1 Shutdown Mode
      2. 9.4.2 Battery Tracking SpeakerGuard™ Operation
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 TPA2015D1 With Differential Input Signals
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1 Boost Converter Inductor Selection
            1. 10.2.1.2.1.1 Inductor Equations
          2. 10.2.1.2.2 Boost Converter Capacitor Selection
          3. 10.2.1.2.3 Components Location and Selection
            1. 10.2.1.2.3.1 Decoupling Capacitors
            2. 10.2.1.2.3.2 Input Capacitors
        3. 10.2.1.3 Application Curves
      2. 10.2.2 TPA2015D1 with Single-Ended Input Signals
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedure
        3. 10.2.2.3 Application Curves
  11. 11Power Supply Recommendations
    1. 11.1 Power Supply Decoupling Capacitors
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Component Placement
      2. 12.1.2 Trace Width
      3. 12.1.3 Pad Size
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Device Nomenclature
        1. 13.1.1.1 TPA2015D1 Glossary
        2. 13.1.1.2 Boost Terms
    2. 13.2 Community Resources
    3. 13.3 Trademarks
  14. 14Mechanical, Packaging, and Orderable Information
    1. 14.1 Package Option Addendum
      1. 14.1.1 Packaging Information
      2. 14.1.2 Tape and Reel Information

9.4.2 Battery Tracking SpeakerGuard™ Operation

Phase 1Battery discharging normally; supply voltage is above inflection point; audio output remains below limiter level.
The limiter level remains constant because the supply voltage is greater than the inflection point. Amplifier gain is constant at fixed-gain as set by the GAIN pin. The audio output remains at a constant loudness. The boost converter allows the audio output to swing above the battery supply voltage. Battery supply current increases as supply voltage decreases.
Phase 2Battery continues to discharge normally; supply voltage decreases below inflection point; limiter level decreases below audio output.
The limiter level decreases as the battery supply voltage continues to decrease. SpeakerGuard™ lowers amplifier gain, reducing the audio output below the new limiter level. The supply current decreases due to reduced output power.
Phase 3Battery supply voltage is constant; audio output remains below limiter level.
The audio output, limiter level, and supply current remain constant as well.
Phase 4Phone plugged in and battery re-charges; supply voltage increases.
The limiter level increases as the supply voltage increases. SpeakerGuard™ increases amplifier gain slowly, increasing audio output. Because the TPA2015D1 supply current is proportional to the PVOUT-to-VBAT ratio, the supply current decreases as battery supply voltage increases.
Phase 5Battery supply voltage is constant; audio output is below limiter level.
SpeakerGuard™ continues to increase amplifier gain to the fixed-gain as set by the GAIN pin. The audio output signal increases (slowly due to release time) to original value.
Phase 6Battery supply voltage is constant; audio output remains below limiter level.
Amplifier gain equal to fixed-gain as set by the GAIN pin. Audio output signal does not change. Supply current remains constant.
GUID-DA127A03-F5EB-4D9B-ADB5-9764C01BD3A6-low.gifFigure 9-7 Relationship Between Supply Voltage, Current, Limiter Level, and Output Audio Signal