JFET
The junction gate field-effect transistor (JFET or JUGFET) is the simplest type of field-effect transistor. It can be used as an electronically-controlled switch or as a voltage-controlled resistance. Electric charge flows through a semiconducting channel between "source" and "drain" terminals. By applying a reverse bias voltage to a "gate" terminal, the channel is "pinched", so that the electric current is impeded or switched off completely.
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