Question

In the given situation for n-channel JFET, we get drain-to-source current is 5mA. What is the current when VGS = – 6V?

(a) 5 mA

(b) 0.5A

(c) 0.125 A

(d) 0.5A

I have been asked this question in semester exam.

The doubt is from Biasing of JFET and MOSFET in division FET Amplifiers of Analog Circuits

Answer 1

The correct option is (c) 0.125 A

The explanation is: IDS = IDSS(1-VGS/VP)^2

When VGS = 0, IDSS = IDS = 5mA

When VGS = -6V, IDS = 5mA(1 + 4)^2

IDS = 5 x 25 = 125 mA.