Hi Khoi, Sorry for slow reply but as Chen explained I was traveling... Anyhow, when you say 100+ sensors I guess you mean that you will need 3 or 4 DDC232 , right? As explained on the DS (start on pg 20), you can cascade them in daisy chain. There are different ways to do that and all work well. You can use MCU or FPGA. That doesn't matter and there is no ns critical timing specs (or jitter, etc...) so you can bitbang the GPIO of the MCU, for instance. Only thing is that it may have to be a "fast" MCU to do so at fast rates... Notice that the CLK and DCLK signals are on the 10-20MHz. Again, you can run them slower but make sure the device can finish all what needs to finish to meet the 500Hz... Just FYI, if you don't know which mode to pick, I am thinking that at 500Hz you may be able to send all the data (100+ channels at 20bit) in the interval that goes from the DVALID to the CONV edge. Just ran the calcs. if so, that is the most forgiving approach from a layout/noise isolation perspective as the data transmission (and whatever toggling noise coming from that) happens at a different instant from the data conversion (from CONV to DVALID). Regards, Edu
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