The LM4921 combines a 16-bit resolution stereo I 2S input digital-to-analog converter (DAC) with a stereo headphone audio power amplifier. It is primarily designed for demanding applications in mobile phones and other portable communication device applications. The LM4921 features an I 2S serial interface for the digital audio information and a 16-bit SPI serial interface for internal register control and communication. With AVDD and DVDD = 3.0VDC and driving a 32Ω single-ended load to a 26mWRMS output level the distortion (THD+N) of the LM4921 will be less than 0.5%. The LM4921 also features a programmable 32-step digital volume control accessed through an SPI interface. Boomer audio power amplifiers were designed specifically to provide high quality output power with a minimal amount of external components. It is, therefore, ideally suited for mobile phone and other low voltage applications where minimal power consumption is a primary requirement. The LM4921 features a low-power consumption shutdown mode, and also has an internal thermal shutdown protection mechanism.