Littelfuse - New unidirectional SIDAC switching thyristors for capacitor discharge applications (Kxxx0S1URP)

Littelfuse has launched two new product series, namely Kxxx0S1URP and Kxxx0GURP series of unidirectional AC thyristor (SIDAC). SIDAC is a semiconductor switch used with capacitors and transformers in capacitor discharge ignition (CDI) circuits to produce high voltage spikes. Compared with existing high-energy SIDAC and standard SIDAC products, the Kxxx0S1URP and Kxxx0GURP series have lower switching losses. The new SIDAC design provides higher repetitive pulse current (ITRM) ratings at higher ambient temperatures, improved breaking / trigger voltage relative temperature characteristics, and lower switching losses. This allows existing circuits to support higher voltage output and ensures stable voltage output at high ambient temperatures. Typical applications for the Kxx0yU series of SIDAC / unidirectional thyristors include high-power flame ignition modules designed for gas cooking equipment, multi-burner models from portable, desktop to commercial grade, gas water heaters and fuel heaters of various sizes, and ion generator . "In a typical high-power gas ignition circuit, SIDAC is like a switch that quickly releases energy from the capacitor," said Daisy Wang, product sales manager for the product line. "The high instantaneous rate of change (di / dt) of the pulsed current from the discharge drives the high pulsed voltage output from the secondary side of the transformer, which creates an ignition spark in the spark gap."