The PCM2704/5/6/7 is TI's single-chip USB stereo audio DAC with USB-compliant full-speed protocol controller and S/PDIF. The USB-protocolcontroller works with no software code, but USB descriptors can be modified in some parts (for example, vendor ID/product ID) through the use of an external ROM (PCM2704/6), SPI (PCM2705/7), or on request. The modification of the USB descriptor through external ROM or SPI must comply with USB-IF guidelines, and the vendor ID must be your own ID as assigned by the USB-IF. The descriptor also can be modified by changing a mask; contact your representative for details. The PCM2704/5/6/7 employs SpAct architecture, TI's unique system that recovers the audio clock from USB packet data. On-chip analog PLLs with SpAct enable playback with low clock jitter.