The Function and Structure of Thyristor

The Function and Structure of Thyristor

One of the main functions of Thyristor is to stabilize voltage and current.

Silicon controlled rectifier is widely used in electric tools, speed regulating motors, vacuum cleaners, dimming lamps, Heat gun, intelligent electric kettles, perm boards, light wave ovens, motorcycle igniters, stove igniters, negative ion generators, leakage protection, Solid-state relay and related electrical control circuits. Thyristor is an active switching element that remains in a non channel state until triggered or "ignited" by a relatively small control signal. Once ignited, even if the trigger signal is withdrawn, it remains in a channel state. To cut it off, a reverse voltage can be applied between its anode and cathode or the current flowing through the Thyristor diode can be reduced to a certain value below.

Structure of Thyristor components

Regardless of the appearance of the Thyristor, their core is a four layer P1N1P2N2 structure composed of P-type silicon and N-type silicon. It has three PN junctions (J1, J2, J3), with anode A introduced from the P1 layer of the J1 structure, cathode K introduced from the N2 layer, and control electrode G introduced from the P2 layer. Therefore, it is a four layer, three terminal semiconductor device.