First discrete thyristor to withstand spikes higher than 1,200V

Littelfuse has introduced its first discrete thyristor devices capable of withstanding voltage spikes higher than 1,200V. The Teccor brand SK225xD/SK255KD/SK625xD/SK655KD Series SCR switching thyristors are unidirectional switches designed to handle voltage spikes and power surges in incoming AC power mains. The SCRs can take up to 1,300V (SK225xD and SK255KD Series) or 1,700V (SK625xD and SK655KD Series) without malfunctioning. The devices are suitable for switching of 50/60Hz AC mains up to 440Vrms. These high voltage SCRs have high repetitive and non-repetitive peak off-stage voltage (VDRM/VDSM) ratings, ensuring reliable operation even when subjected to the high voltage surges common in commercial AC mains power in some areas. Typical applications for the SK225xD/SK255KD/SK625xD/SK655KD Series SCR Switching Thyristors include AC solid-state switches, industrial power tools, and line rectification (50/60Hz), says the company. “These high voltage SCRs are ideal for use as unidirectional switches for AC mains power supplies up to 240Vrms that are subject to frequent voltage surges or mains voltage fluctuations, or up to 440Vrms in stable voltage,” said Daisy Wang, global product marketing manager, SCR switching thyristors. “They are particularly useful in regions where the AC mains voltage is unstable; even 240Vrms or lower lines may have voltage spikes of 1,000V or higher, so a 1,200V or 1,600V SCR may be required.”