We are learning the hybrid parameter model for transistors in school and i dont think that i have ever been so confused in my life!
Like say for example to determine the input resistance for a simple Common Emitter amplifier circuit the lecturer started the formula like so:
Rin = Vbe/Ib (Rin = resistance in, Vbe = voltage between base and emitter, Ib = base current)
How come Rin isn't something like: Rin = Rs + Vbe/Ib (Rs input resistor)
And its the same thing with the output resistor, the load resistor doesn't get taken into account for the output resistance????
Like say for example to determine the input resistance for a simple Common Emitter amplifier circuit the lecturer started the formula like so:
Rin = Vbe/Ib (Rin = resistance in, Vbe = voltage between base and emitter, Ib = base current)
How come Rin isn't something like: Rin = Rs + Vbe/Ib (Rs input resistor)
And its the same thing with the output resistor, the load resistor doesn't get taken into account for the output resistance????