Cmedia Audio-Visual Tech Q&A | Symmetry Blog
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1. Does Cmedia USB audio codec require vendor drivers for a designated operating system?
Cmedia USB audio codecs are classified as UAC 1.0, USB 2.0 Full Speed or UAC 2.0, or USB 2.0 High Speed. The UAC 1.0 has long been supported by built-in drivers for Windows, Linux, MacOS and iOS with known cross-platform compatibility. With the latest updates to Windows 10, UAC 2.0 built-in drivers are now found in Linux, MacOS and iOS, and Windows 10.
2. How do you choose between UAC 1.0 and 2.0 devices from Cmedia?
It depends on the required sample rate of your audio stream. UAC 1.0 devices are capable of supporting up to 24-bit@96KHz and UAC 2.0 aims for high bitrate audio up to 32-bit@768KHz in PCM and 22.4MHz in DSD format.
3. Does Cmedia USB codec require firmware development?
It depends on your device and application requirement. Most USB codecs can operate as plug and play without any firmware development. Source code is available upon request from Cmedia for custom firmware development.
4. Is it possible to customize the Cmedia USB codec design without developing firmware?
Yes, Cmedia offers a PC GUI configuration tool that can be accessed upon request. This tool allows you to customize the USB descriptor (VID/PID), product and manufacturer strings, and audio performance (gain, filtering, EQ, mixer). It also provides a firmware binary base for customization.
5. Does the Cmedia USB Audio Codec depend on USB VBUS power for normal operation, or does it require an external power supply?
Cmedia USB audio codec can operate solely on USB VBUS power; however, an external power supply may be used based on application requirements.
6. Do I need to acquire VID/PID from USB.ORG for my USB audio product?
The VID/PID is the unique identifier to distinguish USB devices and are used by operating systems to locate designated drivers for the USB device. Cmedia allows developers to adopt Cmedia VID along with chip specified PID to be used in their products.