Other Parts Discussed in Thread: PCM1690, , TIDA-01414
Hello,
Currently I'm designing an USB DAC with 10 analogue Outputs, 2 analogue Inputs and 6 digital Inputs.
To archieve this I want to run a XMOS chip (XUF 216). The XMOS has a maximum of 32ch I/O via I2S; in the case of the full 32ch it works via TDM. Around the XMOS Chip I want to use TI hardware to get the analogue outputs and inputs. Because the XMOS is the Master, for the 6 digital Inputs there is the need of asynchronous sample rate converters, in this case SRC4192s. So for 6 channels I need 3 SRC4192s. To get the 2 analogue Inputs I want to use a 2 channel ADC. The main goal of the board is to get the maximum sound quality out of the DACs. At first I just wanted to use two PCM1690, so I can easyly get my 10 channels with two chips only. But I have read, that the PCM1795 is much better at performing and has 32bit, what is very helpful for DSP Processing (Active Crossover, Room Correction and Digital Volume Control). If I go for the PCM1795s I would need at least 5 of them. So there are 5 DACs + 1 ADCs + 3 ASRCs + 1 XMOS Chip. That means I need to distribute the MCLK to 10 chips and the LRCK,BCLK to 9 chips. But how to archieve this? With clock drivers and clock buffers? Would there be a degradation of sound quality when using them and/or additive jitter? And how to route the clocks? Daisy chain? with a bus? or star chained with the buffers like in the dolby atmos soundbar reference design? How to deal with reflections etc?
Thank You very much!
Jens
