I'm just calculating some ABCD paramerters for some amplifiers and I thought I knew this by now, but I can't figure out why the BJT sim, is so different to my AC model sim, just for a CE amp.
I my calculations for A and D match the model spot on, with and without the bypassed emitter, Iin should be 411nA. But the BJT model keeps giving a Iin value about 1.3uA, so ~3x bigger than my calc and the 2 models.
What little thing am I forgetting or overlooking this time ?
I have IB=756.9nA, and D=rm*Gin=3.836mA/A for when RE/Ce is ignored
Would the hybrid-pi model with caps fix this? I'm ready to learn that again, I just never got to using it last time.