Vishay VS-T90RIA120, Thyristor 1200V, 90A 120mA

Single thyristor (SCR) power modules
3500V_RMS isolating voltage from the metal base

These products contain Beryllium Oxide and MUST NOT be cut open or incinerated.

UL E78996 approved

Thyristors - Vishay Semiconductor

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. Thyristors are synonymous to Silicon-Controlled Rectifier (SCR).
Encapsulated modules with electrically isolated base plate. Suitable for applications such as battery chargers, welders and plating equipment, regulated power supplies and temperature and speed control circuits.