What is a thyristor and its classification

The thyristor is the abbreviation of Thyristor, and the thyristor is called thyristor. It is a high-power switch type semiconductor device. It is written in the circuit with the symbols “V” and “VT” (the old standard uses letters. "SCR" stands for).

Thyristors have the characteristics of silicon rectifying devices, can work under high voltage, high current conditions, and its working process can be controlled and widely used in controllable rectification, AC voltage regulator, non-contact electronic switch, inverter and frequency conversion and other electronic Circuit.

First, the type of thyristor thyristor has a variety of classification methods.

(a) Classification of thyristors according to shutdown, conduction, and control modes The thyristors can be classified into common thyristors, bidirectional thyristors, reverse thyristors, gate turn-off thyristors (GTO), BTG thyristors, and temperature according to their turn-off, conduction, and control modes. Control thyristors and light control thyristors and many other.

(b) According to the pin and polarity classification of thyristors according to their pin and polarity can be divided into two-pole thyristor, triode thyristor and quadrupole thyristor.

(III) Classification of thyristors by package types According to their package types, they can be divided into three types: metal-encapsulated thyristors, plastic-sealed thyristors and ceramic-packaged thyristors. Among them, the metal encapsulated thyristor is divided into bolt-shaped, flat-shaped, round shell-shaped and many other; plastic thyristor is divided into two kinds with heat sink type and no heat sink type.

(d) According to current capacity classification thyristor according to current capacity can be divided into high-power thyristor, power thyristor and low power thyristor three. In general, high-power thyristors are mostly packaged in metal shells, while medium- and low-power thyristors are mostly made of plastic or ceramic packages.

(E) Classification of thyristors according to their shutdown speeds The thyristors can be classified into common thyristors and high-frequency (fast) thyristors according to their shutdown speeds.

Fig. 8-1 is a classification diagram of a thyristor, Fig. 8-2 is the appearance of the thyristor, and Fig. 8-3 is a circuit diagram symbol of the thyristor.