TISP4030L1AJR-S is a very low voltage bidirectional thyristor overvoltage protector designed to provide 2-point protection for transformer windings and low voltage electronics. The device features a symmetrical voltage-triggered thyristor that initially clips overvoltages through breakdown clamping until the breakover voltage is reached, at which point it transitions to a low-voltage on-state condition to safely divert surge current. With a breakover voltage of ±30 V, repetitive peak off-state voltage rating of ±15 V, and low capacitance of 27 pF, this device is optimized for digital line signal protection applications including ISDN and xDSL systems. The protector switches off when the diverted current falls below the holding current threshold, providing reliable protection while maintaining signal integrity in sensitive communication circuits.