This document describes a filter-free class-D audio power amplifier with 6 or 12 dB fixed gain select. It operates from 2.4V to 5.5V and provides output power of 1.4W at 5V or 0.5W at 3.0V into 8Ω with 1% THD+N max. The amplifier features low current consumption, high efficiency, and low noise. It is suitable for applications such as cellular phones, PDAs, and notebook PCs.