The TPA3221EVM HD-Audio evaluation module demonstrates the TPA3221 integrated circuit from Texas Instruments. TPA3221 is an ultra-low idle-loss Class-D amp which keeps your system cooler and your battery playing longer while supporting 100kHz high resolution audio and features single-rail power supply support, gain settings, mute, and integrated protection. The device features advanced integrated feedback design which allows very low distortion across the audio band and enables a high audio quality. The device is operated in either HEAD-mode (High-Efficiency-AD) or AD-mode Pulse Width Modulation (PWM) and can drive up to 2 x 100 W into 4-Ω load or 2 x 130 W into 3-Ω load. The TPA3221EVM features adjustable gain settings from 18-34dB, and allows for flexible input signals with a 1-2 VRMS single-ended / differential analog input interface. This EVM supports 2 x BTL (stereo) output channels or 1 x PBTL (mono) output channel configurations. TPA3221EVM is a complete reference design for TPA3221, ready for evaluation and excellent listening.