Member level 4
I am designing a current measurement circuit. The circuit involves more than one shunt resistance in order to cover different ranges of current. I would like to access any of them using 1 channel and switch between the shunts using relays but the minimum shunt resistor I am using is 50 mOhm and the relays have contact resistance within 30 to 100 mOhms so the values of the contact resistance is going to completely change the milli volt values that I am sensing over the shunt. My question is what are the alternatives , are there any relays with ultra low contact resistance 1 mOhms forexample? I can't use transistors because I need guaranteed isolation. Thank you very much in advance!