A thyristor is a solid-state semiconductor device with four layers of alternating N and P-type material. They act as bistable switches, conducting when their gate receives a current trigger, and continue to conduct while they are forward biased (that is, while the voltage across the device is not reversed).
Some sources define silicon controlled rectifiers and thyristors as synonymous.
Other sources define thyristors as a larger set of devices with at least four layers of alternating N and P-type material, including:
- Distributed Buffer - Gate Turn-off Thyristor (DB-GTO)
- Gate turn-off thyristor (GTO)
- Integrated gate commutated thyristor (IGCT)
- MOS composite static induction thyristor/CSMT
- MOS Controlled Thyristor (MCT)
- Reverse conducting thyristor
- Silicon controlled rectifier (SCR)
- Static induction thyristor (SITh)
- Triode AC switch (TRIAC)
Read more about Thyristor: Introduction, History, Applications, Comparisons To Other Devices, Failure Modes, Silicon Carbide Thyristors, Types of Thyristor