The CS4205 is an AC ’97 2.1 compliant stereo audio codec designed for PC multimedia systems. It uses industry leading CrystalClear® delta-sigma and mixed signal technology. The CS405 is the first Cirrus AC ’97 audio codec to feature digital centric mixing and digital effects. This advanced technology and these features are designed to help enable the design of PC 99 and PC 2001 compliant high-quality audio systems for desktop, portable, and entertainment PCs.