JFET stands for junction field-effect transistor, a simple three-terminal semiconductor device where a voltage applied to the gate terminal pinches off the current flowing between the source and drain. Unlike MOSFETs, JFETs do not have an insulating oxide layer, making them highly reliable and immune to static discharge damage, though they are strictly depletion-mode devices.
We used a JFET in the input stage of the microphone preamp for its extremely low noise floor.
Also heard as
- junction field-effect transistor
Related terms
MOSFET
A metal-oxide-semiconductor field-effect transistor is a voltage-controlled switch used to amplify or switch electronic signals.
FET
A field-effect transistor controls the flow of electrical current using an electric field.
Transconductance
The electrical property relating the current output of a device to its voltage input.