Question

What is trans-conductance?

(a) Ratio of change in drain current to change in collector current

(b) Ratio of change in drain current to change in gate to source voltage

(c) Ratio of change in collector current to change in drain current

(d) Ratio of change in collector current to change in gate to source voltage

I have been asked this question in homework.

My doubt stems from The FET Small-Signal Model topic in division Field-Effect Transistors of Electronic Devices & Circuits

Answer 1

Right option is (b) Ratio of change in drain current to change in gate to source voltage

Easy explanation: The change in drain current which is resulted due to change in gate to source voltage in a FET is measured by trans-conductance. This is termed as trans because it provides relationship between input and output quantity.