150 V rail protection in a 400 W footprint
The SMAJ150A-13: Its 150 V reverse standoff voltage means it sits across the line without conducting during normal operation, then triggers at a minimum breakdown of 167 V to shunt the surge. The 243 V maximum clamping voltage at the 1.6 A peak pulse current defines the voltage the protected IC sees — keep this below the downstream device's absolute maximum rating.
Rated at 400 W peak pulse power for the standard 10/1000 µs exponential waveform — this is the energy-handling benchmark for TVS diodes in signal and low-power data lines. The 1.6 A peak pulse current at that waveform tells you the surge current the part can sink before the junction overheats. The power line protection flag is set to No, confirming this device is intended for signal or data-line transient suppression, not for clamping mains or high-energy power bus surges.
DO-214AC SMA — board-fit and thermal path
Housed in the DO-214AC (SMA) package, a surface-mount footprint common across the SMAJ series. The cathode tab on the SMA package is the primary heat path — the PCB copper pad area under it sets the junction-to-ambient thermal resistance.