I'm having a lot of trouble with more complex transistor DC circuits (can't wait for the AC, heh). Basically, what I want to ask is does KVL holds "around" a transistor as well?
For example, if I have a p-type MOSFET, and I successfully calculate Vsd and Vdg, can I find Vsg like Vsg=Vsd+Vdg? I think I remember seeing that this is true only in saturation mode, but I can't seem to find it again anywhere for the life of me. Similarly, can I go "through" a wire when doing BJT circuits? What I mean is, if I know that BJT is in saturation (and Vbe=0.7, Vce=0.2), is it allowed to have both of them in the equation while doing KVL (effectively going through the emitter wire).
TL;DR: Is it valid to write Ib*Rb+Vbe-Vce=0 regardless of the mode of operation. Same for the MOSFETs?