Hello,
I'm having a bit of trouble syncing the ADC and the DSP. The DSP is on the non-isolated side of the board and the ADC is on the isolated side of the board. The sides are separated by digital opto-couplers. For noise reasons, I am not able to put the DSP on the isolated side of the board.
The DSP sends the clock and the sync signals across the digital opto-couplers and triggers the ADC to send its data bits back across the digital opto-coupler to the DSP. The problem that I'm encountering is that the propagation delay through the digital opto-couplers is too long. The isolation scheme adds almost a full bit time and the DSP saw all the data shifted by a bit or two, with at least one bit lost completely.
I then tried sending the data and clock across the opto-coupler to the ADC, and then sent two signals back across the opto-coupler with the data to the DSP, so that everything was delayed, and had the DSP sync to the incoming clock, instead of the outgoing clock. This solution, mostly worked.
Is there an easier way to sync these signals?
Thanks