1.5 kW TVS in a DO-214AB — what the SM15T10A does
The STMicroelectronics SM15T10A is a single-channel unidirectional Zener TVS diode from the TRANSIL™ family, designed to clamp voltage transients on general-purpose power and signal lines. It delivers 1500 W (1.5 kW) peak pulse power per the 10/1000 µs waveform, with a clamping voltage of 18.6 V at the rated peak pulse current of 538 A (8/20 µs waveform). The 8.55 V reverse standoff voltage means it stays out of the way on a nominal 5 V or 3.3 V rail, only clamping when the line exceeds the 9.5 V minimum breakdown threshold. Packaged in a DO-214AB (SMC) surface-mount case, it suits board-level transient protection in industrial controls, telecom equipment, and power supplies where a single unidirectional clamp is sufficient.
The SM15T10A carries an Obsolete lifecycle status. For existing designs, the part must be sourced through independent distribution or surplus channels. The 1.5 kW peak pulse rating and DO-214AB footprint are common across the TRANSIL™ family, so a parametric replacement — such as a higher-voltage variant in the same package — may be feasible, but no pin-compatible drop-in is formally designated. Any substitution requires a review of the clamping voltage and breakdown thresholds against the protected circuit.
Temperature range and mounting
The SMC footprint is standard for 1.5 kW TVS diodes, making board layout straightforward if a replacement is needed.