How is FET a voltage controlled device?


A Field-Effect Transistor (FET) is a voltage-controlled device as its operation is primarily governed by the voltage applied to the gate terminal.

How is FET a voltage controlled device.
How is FET a voltage controlled device.


In an FET, the gate voltage establishes an electric field that controls the flow of charge carriers between the source and drain terminals. This voltage-induced field modulates the conductivity of the semiconductor channel, enabling precise control over the current flow.


Q: How does an FET work?

A: By applying a voltage to the gate, which controls the flow of current between the source and drain.

Q: What are the types of FETs?

A: Common types include MOSFETs (Metal-Oxide-Semiconductor FETs) and JFETs (Junction Field-Effect Transistors).

Q: Why is voltage control advantageous?

A: Voltage control allows for high input impedance, low power consumption, and efficient signal amplification.

Q: Are FETs unipolar or bipolar devices?

A: FETs are unipolar devices, relying on either electrons (N-channel) or holes (P-channel) for conduction.

Q: What is threshold voltage in FETs?

A: It’s the minimum gate voltage required to establish a conducting channel between the source and drain.

Q: Can FETs be used for switching applications?

A: Yes, FETs are widely employed in digital circuits for their fast switching capabilities.

Q: How does temperature affect FET performance?

A: Temperature can influence threshold voltage and impact overall FET characteristics.

Q: What is the difference between N-channel and P-channel FETs?

A: N-channel FETs use electrons for conduction, while P-channel FETs use holes.

Q: Are FETs more sensitive to static electricity than other transistors?

A: Yes, FETs can be more sensitive, and precautions are necessary to prevent damage.

Q: Can FETs be used in radio frequency (RF) applications?

A: Absolutely, FETs are commonly employed in RF amplifiers and mixers.