A field-effect transistor relies on an electric field to control the conductivity of a semiconductor channel. Voltage applied to the gate terminal alters the width of the charge carrier channel between the source and drain, effectively acting as a voltage-controlled resistor. Because they draw almost no input current at the gate, these devices offer high input impedance and are the foundational building blocks for most integrated circuits.
Check the datasheet to see if that FET can handle the gate drive voltage before we spin the new board revision.
When troubleshooting a dead circuit, remember that a FET can be easily destroyed by static electricity if the gate is left floating.
Related terms
MOSFET
A metal-oxide-semiconductor field-effect transistor is a voltage-controlled switch used to amplify or switch electronic signals.
JFET
A type of field-effect transistor that uses a reverse-biased junction to control current.
Source
The terminal of a field-effect transistor where majority charge carriers enter the channel.
Drain
One of the three main terminals on a field-effect transistor.