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.