Hello, everyone!

I have a project design, where is an instrumentation amplifier. The input resistance of the circuit has to be 1M Ohm, and I have no idea how to calculate value of the resistors. I tried to google, but nothing useful was found. Can you help me with formulas?

 

hi,
A good starting point would be to use an existing IA circuit, refer the image.

The resistors must be close tolerance 0.1% or better if possible, use a CMOS OPA or FET input OPA.

E

 

Instrumentation Amplifier Application Note - page 3.