Question

What is the approximate hybrid parameter voltage gain of a CE amplifier?

(a) hfe × RL / hie

(b) -hfe × RL / hie

(c) hfe × RL / hoe

(d) -hfe × RL / hoe

I had been asked this question during an internship interview.

Question is from Approximate Hybrid Model and its use in CE, CB, CC topic in portion Small-Signal Low-Frequency AC models of Transistors of Electronic Devices & Circuits

Answer 1

Correct choice is (b) -hfe × RL / hie

Best explanation: The voltage gain of a common emitter (CE) amplifier can be expressed in terms of approximate hybrid parameters. The voltage gain is equal to -hfe × RL / hie where, RL is load resistance, hie is input resistance and -hfe is the current gain.