The PCM2900B/2902B is Texas Instruments' single-chip, USB, stereo audio codec with a USB-compliant full-speed protocol controller and S/PDIF (PCM2902B only). The USB protocol controller requires no software code, but the USB descriptors can be modified in some areas (for example, vendor ID and/or product ID). The PCM2900B/2902B employs SpAct architecture, TI's unique system that recovers the audio clock from USB packet data. On-chip analog PLLs with SpAct architecture enable playback and record with low clock jitter as well as independent playback and record sampling rates.