Question

Which external parameters affect the transistor hybrid parameters?

(a) Temperature

(b) Collector current

(c) Temperature and collector current

(d) External parameters don’t affect hybrid parameters

I have been asked this question in examination.

Question is taken from Conversion Formulas for the Parameters of the Three-Transistor Configurations topic in section Small-Signal Low-Frequency AC models of Transistors of Electronic Devices & Circuits

Answer 1

Right answer is (c) Temperature and collector current

Explanation: The transistor hybrid boundaries are not consistent and change with temperature, collector current and collector emitter voltage. Consequently, while planning the circuit the hybrid boundaries ought to be estimated under similar conditions as the actual circuit.