New thyristors safeguard SLIC interfaces from lightning-induced surges and power fault events

Littelfuse has introduced two series of SIDACtor protection thyristors designed to protect SLIC interfaces against lightning-induced surges and power fault events. The surface-mount B61089QDR and B9110DF Series thyristors for programmable tracking protection contain fast-switching crowbarring structures that are compatible with the Basic levels outlined in the ITU K.20, K.21 and K.45 recommendations from the ITU. The B61089QDR Dual-Port Battrax provides surge protection for SLIC cards that have only implemented negative voltage ringing. The B9110DF Series provides surge protection for SLIC cards that have implemented both positive and negative voltage ringing, which are used in most telecommunications applications today. It also tracks the Vcc reference of the SLIC chipset so that if and when it enters a low quiescent stage, the protection threshold will match this lower threshold.