A thyristor is a four-layer semiconductor device with alternating P-type and N-type materials. A Thyristor usually consists of three electrodes: an anode (positive terminal), Cathode (negative terminal) and a gate. The gate is the main control terminal while the main current flows between the anode and cathode.
It acts exclusively as a switch, conducting when the gate receives a current trigger, and continuing to conduct until the voltage across the device is reversed, or until the voltage is completely removed.
Shop Express Electronics range of thyristor semiconductors below.