-Refer to the figure above. In this circuit, VGS is biased correctly for proper operation. This means that VGS is
A)0 V.
B)positive.
C)negative.
D)either negative or positive.

Question

-Refer to the figure above. In this circuit, VGS is biased correctly for proper operation. This means that VGS is
A)0 V. 
B)positive. 
C)negative. 
D)either negative or positive.

Quizplus · Accepted Answer

For proper operation in a typical enhancement-mode N-channel MOSFET, VGS must be positive to attract electrons towards the gate, creating a channel between the source and drain. However, for a P-channel MOSFET, VGS needs to be negative to attract holes towards the gate to create a channel. Since the question does not specify the type of MOSFET, the assumption based on common usage would be incorrect. The correct operation of a MOSFET, whether N-channel or P-channel, requires VGS to be biased correctly, which means it can be either positive or negative depending on the type of MOSFET. My previous explanation mistakenly focused on N-channel MOSFETs, neglecting the context of P-channel MOSFETs where VGS is negative for proper operation.

-Refer to the Figure Above