The TISP4240M3BJR-S is a bidirectional thyristor overvoltage protector designed to safeguard telecommunication equipment from transient voltage events. It features a repetitive peak off-state voltage (VDRM) of 180 V and a breakover voltage (V(BO)) of 240 V. When a surge exceeds its breakover level, the device crowbars into a low-voltage on-state, diverting the excess current to protect downstream components. This protector can withstand significant surge events, such as a 100 A peak pulse for a 10/700 µs waveform. Housed in a surface-mount SMBJ package, it is commonly used for 2-point protection in 2-wire equipment like telephones and modems against lightning and AC power disturbances.