Hi,there!
I want to simplify my 5 mosfet amp which is consist of diff. pairs with resistor load.I heard that you can use VCCS to replace the input diff. pairs, and the ggain is set to the gm of the input transistor. I know the small signal current can be denoted as i=gm*vgs, then the VCCS can model the small signal current correctly.But,if there is only one VCCS with gm, what about the DC operating point? For the total current is not equal to gm*vgs but 0.5*u*C*(Vgs-Vth)^2. So,only using one VCCS,can it model the input differential pairs accurately?
Regards
urian