I'm trying to figure out how to implement an auto range by changing the resistors values for R2 and R3 with a MCU. First I was thinking of using a mux like the ADG5208BCPZ, but I think I might fry the chip depending on the input voltage (like 100v). I am considering on making a mux using relays, but I'd like to try a more compact option. Can someone explain to me how add this functionality to my circuit?
I have designed a board with an AD7794 with inputs to read analog signals, but each differential pair had a set range (+-0-1.17V, 2x +-0-100V, 0-5A, 0-100kOhm (they all have input protection)) and I used the ADC's gain to have a pseudo auto range. But there are some things I want to improve, like adding an instrumentation amp between the signal and the ADC and an actual range select.