• On-Chip USB Interface:
  • No Dedicated Device Driver Needed
  • Full-Speed Transceivers
  • Fully Compliant With USB 2.0 Specification
    • USB 1.1 Descriptors With USB Audio Class Support
  • Certified by USB-IF
  • Partially Programmable Descriptors
  • Adaptive Isochronous Transfer for Playback
  • Bus-Powered or Self-Powered Operation
• Sampling Rates: 32 kHz, 44.1 kHz, and 48 kHz
• On-Chip Clock Generator With Single 12-MHz Clock Source
• Single Power Supply:
  • Bus-Powered: 5 V, Typical (VBUS)
  • Self-Powered: 3.3 V, Typical
• 16-Bit Delta-Sigma Stereo DAC
  • Analog Performance at 5 V (Bus-Powered), 3.3 V (Self-Powered):
    • THD + N: 0.006% RL > 10 kΩ, Self-Powered
    • THD + N: 0.025% RL = 32 Ω
    • SNR = 98 dB
    • Dynamic Range: 98 dB
    • PO = 12 mW, RL = 32 Ω
  • Oversampling Digital Filter
    • Passband Ripple = ±0.04 dB
    • Stop-Band Attenuation = –50 dB
  • Single-Ended Voltage Output
  • Analog LPF Included
• Multiple Functions:
  • Up to Eight Human Interface Device (HID) Interfaces (Model and Setting Dependent)
  • Suspend Flag
  • S/PDIF Out With SCMS
  • External ROM Interface (PCM2704C/6C)
  • Serial Programming Interface (PCM2705C/7C)
  • I2S Interface (Selectable on PCM2706C/7C)

• USB Headphones
• USB Audio Speaker
• USB CRT/LCD Monitor
• USB Audio Interface Box
• USB-Featured Consumer Audio Product

The PCM270xC are TI's single-chip USB stereo audio digital-to-analog converters (DACs) with USB 2.0 compliant full-speed protocol controller and S/PDIF. The USB-protocol controller works with no software code, but USB descriptors can be modified in some areas (for example, vendor ID/product ID) through the use of an external ROM (PCM2704C and PCM2706C) or serial peripheral interface (SPI) (PCM2705C and PCM2707C). The PCM270xC also employ SpAct™ architecture, TI's unique system that recovers the audio clock from USB packet data. On-chip analog phase-locked loops (PLLs) with SpAct enable playback with low clock jitter.