TISP4030H1BJR-S is a very low voltage bidirectional thyristor overvoltage protector designed for digital line signal level protection in ISDN and xDSL applications. The device features a symmetrical voltage-triggered thyristor that initially clips overvoltages through breakdown clamping, then transitions to a low-voltage on-state condition when voltage rises to the breakover level, safely diverting surge current through the device. It operates with a repetitive peak off-state voltage (VDRM) of ±15 V and a breakover voltage (V(BO)) of ±30 V, with low capacitance of 62 pF typical at 1 MHz. The device is housed in an SMB (DO-214AA) package and is RoHS compliant, making it suitable for transformer winding protection and low voltage electronics in telecommunications and data communication systems.