Question

Q point can be set to work on active region requires particular conditions. What are they?

(a) BE reverse biased and BC forward biased

(b) BE reverse biased and BC reverse biased

(c) BE forward biased and BC reverse biased

(d) BE forward biased and BC forward biased

The question was posed to me during an interview for a job.

Asked question is from The Operating Point in section Transistor Biasing and Thermal Stabilization of Electronic Devices & Circuits

Answer 1

Correct answer is (c) BE forward biased and BC reverse biased

To explain: BJT requires the forward voltage nearly equal to 0.7v and the p-junction should be more positive in BE junction and n region should be more positive in BC junction. This will make the current to flow through emitter which is the sum of current through base and emitter.