1.5 kW TVS for telecom line protection
The 1.5SMC20A V7G is a 1500W peak-pulse-power Zener TVS diode from Taiwan Semiconductor's 1.5SMC series, designed to clamp transients on telecom and industrial DC buses. Its 17.1V reverse standoff voltage means it stays transparent on a 12V or 15V rail and only conducts when the line exceeds that threshold, shunting the surge to ground. The 1500W rating is the peak power the die can absorb in that pulse — enough for secondary protection in a central-office line card or an outdoor radio unit.
Package and board-fit
Housed in the DO-214AB (SMC) surface-mount package, the part measures roughly 7.1 x 6.2 mm with a seated height around 2.6 mm. The SMC footprint is larger than the SMA sibling, which translates to better heat sinking into the PCB copper — relevant when the TVS sees repetitive surges, not just a single event. The unidirectional configuration (single channel) means the cathode band on the package must align with the positive rail; reverse the polarity and the diode conducts at the forward voltage instead of the Zener breakdown.