-The JFET in Figure has the following ratings: VGSoff) = -2 V to -10 V, gm0 = 1000 μS to 1600 μS. What is the approximate input impedance of the circuit?
A) 179 kΩ
B) 1 MΩ
C) 848 kΩ
D) 922 kΩ

Question

-The JFET in Figure has the following ratings: VGSoff) = -2 V to -10 V, gm0 = 1000 μS to 1600 μS. What is the approximate input impedance of the circuit?
A) 179 kΩ 
B) 1 MΩ 
C) 848 kΩ 
D) 922 kΩ

Quizplus · Accepted Answer

The input impedance of a JFET (Junction Field-Effect Transistor) circuit is primarily determined by the gate-source junction. Since the gate-source junction is reverse-biased in normal operation, it behaves like a reverse-biased diode, which has a very high resistance. This high resistance, often in the range of megaohms, makes the input impedance of the JFET circuit very high. Therefore, among the given options, 1 MΩ is the most reasonable approximation for the input impedance of the circuit.

-The JFET in Figure Has the Following Ratings: VGSoff) =