I run the simulation on diff pair positive input connected with negative input and I want to find input common mode diff pair.
I run .dc analisys...
.dc vin 0 vdd 0.001
Could you say please how I can find input common mode in this simulation?
Common Mode Terminology is concerned with AC Signals.So, you should apply an AC signal when these Inputs are connected together then you look the Output.
After that Compare Output to Input in dB.