I'm wanting to get an analog signal output equal to the differential signal IN X gain. In other words, if I have input A = 11V and input B=12V and Gain = 1, then I want an output signal of 1V. Is this what common mode rejection is? ie. it takes the difference in the signals and not the reference voltage of the signals. I want the same output if IN A=1V and IN B=2V or IN A=5V and IN B = 6V. The application involves current sense resistors and mosfets to switch in/out resistances, or perhaps high side resistors. I want to isolate the voltage drop across the resistors and ignore the actual voltage level the resistors are at.