Hello,
I would like to ask a couple of questions about the master clock signal required of any audio DAC or ADC device, internally or externally generated. I have a situation where there is no way to share the master clock used by my ADC's with the processor that can only generate its own MCLK internally. This means that only the bit clock, frame sync and data signals are connected between host processor and ADC.
I am wondering if there is the possibility of jitter that will degrade the quality of the audio captured as a result of this. The ADC will have a high quality reference clock generated specifically for it so I know it will be exactly 256fs and 512fs as required. The master clock in the processor is a divided value of its own CPU clock and I'm still investigating how close I can get to the exact 256fs and 512fs of the data clock. I think I can get 24MHz for the real 24.576MHz clock and 12MHz for the real 12.288MHz clock. It's based around 12MHz due to USB timings.
My second question would be just how important the MCLK in the host CPU even needs to be if the data collection is just triggered by edges of the bit clock anyway (ADC as master). Perhaps it only needs to be fast enough inside the CPU to be sure it never misses those edges which I can definitely guarantee with the maximum setting.
Thanks!
