The CS4271 is a high-performance, integrated audio CODEC. The CS4271 performs stereo analog-to-digital (A/D) and digital-to-analog (D/A) conversion of up to 24-bit serial values at sample rates up to 192 kHz. The D/A offers a volume control that operates with a 1 dB step size. It incorporates selectable soft ramp and zero crossing transition functions to eliminate clicks and pops. The D/A’s integrated digital mixing functions allow a variety of output configurations ranging from a channel swap to a stereo-to-mono downmix. Standard 50/15µs de-emphasis is available for sampling rates of 32, 44.1, and 48 kHz for compatibility with digital audio programs mastered using the 50/15 µs preemphasis technique. Integrated level translators allow easy interfacing between the CS4271 and other devices operating over a wide range of logic levels. An on-chip oscillator eliminates the need for an external crystal oscillator circuit. This can reduce overall design cost and conserve circuit board space. The CS4271 automatically uses the on-chip oscillator in the absence of an applied master clock, making this feature easy to use.