High Temp SCRs STMicroelectronics High Temp SCRs are used in controlled rectifier bridges, current limiters, AC relays, or as HV crowbar protection for SMPS. The SCRs perfectly suit compact equipment and are 12A to 80A 600V to 1200V range rated at a 150°C Tj. The 150°C junction temperature gives headroom for smaller heatsink and higher load control, whether for solid state relays or motor starters.