Diode-connected transistor

A diode-connected transistor is a method of creating a two-terminal rectifying device (a diode) out of a three-terminal transistor. A characteristic of diode-connected transistors is that they are always in the saturation region for metal–oxide–semiconductor field-effect transistors (MOSFETs) and junction-gate field-effect transistors (JFETs), and in the active region for bipolar junction transistors (BJTs).

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