Question

The h-parameters analysis gives correct results for __________

(a) large signals only

(b) small signals only

(c) both large and small

(d) not large nor small signals

The question was posed to me in a job interview.

Question is from Transistor Hybrid Model topic in section Small-Signal Low-Frequency AC models of Transistors of Electronic Devices & Circuits

Answer 1

Right option is (b) small signals only

Easiest explanation: Every linear circuit is associated with h –parameters. When this linear circuit is terminated with load rL, we can find input impedance, current gain, voltage gain, etc in terms of h-parameters. For small a.c. signal, transistor behaves as linear device. Under such circumstances the a.c. signal operation of a transistor can be described in terms of h-parameters.