Question

In CE arrangement, the value of input impedance is approximately equal to _____

(a) HIE

(b) HIB

(c) HOE

(d) HRE

The question was asked during an interview.

I want to ask this question from Transistor Hybrid Model in division Small-Signal Low-Frequency AC models of Transistors of Electronic Devices & Circuits

Answer 1

Correct answer is (a) HIE

The explanation: hie = vBE/ib; common emitter input impedance

                           For VCE = 0   i.e. output short circuited

Where vBE =Base emitter voltage   i.e. input voltage

               ib =  Base current  i.e. input current.