Thanks for the reply Sean. I'll go forward with this approach, and update when I've verified that it works.
It is recommended to use the ADG5409 with a minimum of 9V as the supply.
Is there a reason you chose the ADG5409, other than low resistance? These are latchup proof parts and hence are more robust to electrical stresses. Do you see this…
Have you any more details on what the fault is that is damaging the part? Is it a positive or negative over voltage condition?
I have attached a tutorial which outlines protection methods to be used. You have implemented one of them but…
Today I repeated the test in two situation as bellow, Ch1, Ch2 are installed with AD8421, Ch2, Ch4 are installed with AD8429. In Ch1, the gain mux ADG1404 is removed to elminate any possible reason from Mux, and pin 5, 6 are shorted to have…