I have a differential amplifier. Problem of "gain" of the op-amp or "how it is wired."
- I have simulated this as a voltage source controlled voltage (VofV.)
- As a generic amplifer.
- As a good old LM741C.
Very strange behavior when there is an error of "wiring." But quasi good results.
What is happening?
Precision : it is a "Dynamics-DC" analysis (so called) by microp12 Spectrum-Software ... and the results are, I think so, "numerically" correct.
EDIT : for obtaining what are "real" and correct results, one must make some other analysis on these examples, as TRANsient analysis. So, when you have a circuitry to be analysed, always try different kind of simulation. And, "in fine", ... Realize in a 'real world' by assembling it on a breadboard ... and viewing on a scope (or other toosl) the behavior. When you use "simulators" or "mathematical" tools, don't forget to verify some "answers" given. Be critical ...