UC350

Improved USB interlink for digital audio

USB was developed to connect peripherals like printers, scanners, mice, keyboards and storage devices to a PC, not for streaming digital audio. Incorrect received data can be re-sent as many times as required to ensure correct data transfer. The 5V USB bus power supply was intended to power peripherals that draw a maximum current of 500mA. Noise is of less importance as long as the peripheral works as intended.

As computer-based digital audio streaming became popular, USB was (mis)used for digital audio streaming. Because of related real-time data stream, there is no time for re-sending incorrect data. Incorrectly received data remains incorrect. USB audio devices are also highly sensitive to noise, this noise cannot be blocked as relatively large bandwidth interface is required to get the data through. Noise that falls within this digital audio interface bandwidth can enter the digital audio receiver and connected circuits like a DAC without any problems. Re-clockers won't help as these only attenuate jitter, not noise.

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