SLAA856A July   2018  – July 2021 TAS5825M

 

  1.   Trademarks
  2. 1General Overview
  3. 2Advanced Emission Suppression
    1. 2.1 Spread Spectrum Modulation
    2. 2.2 Dephase and Multi-Device Phase Synchronization
  4. 3Printed Circuit Board Design for EMC
    1. 3.1 Printed Circuit Board Layout
    2. 3.2 Ferrite Bead Filter
    3. 3.3 Power Supply and Speaker Wires
    4. 3.4 TAS5825M Device Configurations
  5. 4TAS5825M EMI Test Results
    1. 4.1 EN55022 Radiated Emission Results
    2. 4.2 EN55022 Conducted Emission Results
    3. 4.3 Conclusions
  6. 5Revision History

1 General Overview

The emphasis on green technologies and sleek-looking electronics (such as the flat panel TV) has lead manufacturers to produce space-efficient and attractive products without sacrificing performance. The TAS5825M Class-D audio power amplifier provides Class AB audio performance using only the PCB as heat sink due to its high efficiency. In addition, the TAS5825M device has advanced PWM modulation and switching schemes that help reduce EMI while eliminating the need for the traditional Class-D output filter. PWM filtering requires only smaller and less expensive RF filter components. No external heat sink and less RF filtering result directly in PCB size reduction.

Discussions in the following sections explain the PCB layout practice and external components selection in order to achieve optimal audio performance and pass electromagnetic compatibility (EMC) specification EN55022.

  • Section 2 describes the advanced emission suppression techniques used to combat EMI.
  • Section 3 discusses the PCB design guidelines for audio quality and EMC.
  • Section 4 shows the EMC results.