The TAS5404-Q1 device is a four-channel class-D audio amplifier designed for use in automotive head units. The TAS5404-Q1 device provides four channels at 20 W continuously into 4 Ω at less than 1% THD+N from a 14.4-Vdc supply when used with the application circuit. The input is configured as an analog single-ended interface. The patented PWM topology of the device provides dramatic improvements in efficiency and audio performance over traditional linear amplifier solutions. The improvement in efficiency and audio performance reduces the power dissipated by the amplifier by a factor of ten under typical music playback conditions. The device incorporates all the required functions required by the OEM application. The built-in load diagnostic functions for detecting and diagnosing disconnected speakers help reduce test time during the manufacturing process.