USB AUDIO 2.0 REFERENCE DESIGN

XMOS USB Audio solutions utilize High Speed USB 2.0 with 480Mb/s of audio data, delivering 24-bit audio, sample frequencies up to 192kHz and from 2 to 40 audio channels. The highly flexible XMOS devices allow you to tailor your solution to the exact mix of interfaces and digital processes for your product.

This USB Audio solution utilizes the XS1-L8-64 device to provide high quality digital audio connectivity for pro-audio and consumer applications. The design provides certified USB 2.0 High Speed device and Audio Class 2.0 device class implementations with configurable digital audio interfaces, peripherals and the ability to integrate audio processing. The framework also includes support for USB Audio Class 1.0.

Features

  • Complete reference design
  • Stereo audio input via I2S
  • Stereo audio output via I2S
  • Optical digital audio output (S/PDIF)
  • Bit perfect digital audio data, 24-bit @ 192kHz
  • The industry's lowest round-trip audio latency
  • Supports standard sample rates - 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz**, 192kHz
  • USB bus-powered. No external power supply required
  • Low jitter audio master clocks using asynchronous USB synchronization
  • Built on the 500 MIPS, 8 cores, XS1-L8-64 processor
  • XMOS XSYS debug header for easy programming/debug from the host using the XMOS XTAG2 debug adapter
**176.4kHz SPDIF not supported on L8 USB Audio board. 176.4KHz SPDIF requires use of 22.5972MHz crystal instead of 11.2896MHz
USB Audio xTAG

Driver support

The XMOS USB Audio firmware supports both USB Audio Class 1.0 and USB Audio Class 2.0. Operation with a USB Audio Class 2.0 host is preferred because of its extended feature set and use of USB 2.0.

Apple OSX version 10.6.4 and above natively supports USB Audio Class 2.0 – no driver install is required.

Windows, however, only provides support for USB Audio Class 1.0. To use a USB Audio Class 2.0 device under Windows requires a driver. XMOS therefore provides a free Windows USB Audio driver for evaluation and prototyping, a free stereo-only driver for production, and a path to a more feature-rich multichannel production driver from Thesycon.

Download the USB Audio Class 2.0 Evaluation Driver for Windows or see the USB Audio Class 2.0 Windows Driver Overview for further details.

Evaluation and production Windows drivers are also available from our partners CEntrance or Ploytec.

Designing USB Audio 2.0 products

The USB Audio 2.0 Reference Design is based on the XS1-L8-64 xCORE-General Purpose device. We recommend that new USB Audio 2.0 designs should be based on xCORE-USB devices instead of xCORE-General Purpose devices. See USB Audio DJ Kit for an example.