Audio Master Clock Source

[CallumSmithSound]

The XMOS dev board has 3 possible clock sources:

• A Cirrus Logic CS2100CP
• A Skyworks Si5351
• An PLL output from the XMOS

The Cirrus Logic clock seems the most supported in XMOS libraries. It has support for external sources (World Clock / SPDIF) which the other sources do not. However, I'm not using these sources. Also the CS2100CP is expensive (~£6 vs ~£1.65 for the Si5351) and is now obsolete.

The PLL output from the XMOS has high jitter so that would be a last resort. This leaves the skyworks, which needs testing.

[CallumSmithSound]

Another Advantage of the Skyworks Si5351 is that it would entirely fix an adress conflict between the CS2100CP and the DACs removing the need for a I²C multiplexer. Due to the fact that I'm using less DACs than the dev board, it would be trivial to remove the I²C multiplexer. This would only become an issue if I tried to design a board with a higher channel count