The 1.5SMCJ16A_R1_00001: The clamping voltage at 57.7A (26V) is the governing number for downstream IC protection, not the headline wattage alone. The DO-214AB (SMC) package with its tab area is the thermal key — the cathode tab carries heat away from the junction during the transient; adequate pad geometry on the PCB is what the supplier device package drawing assumes.
1.5SMCJ family — what this series is for
The 1.5SMCJ series is a general-purpose unidirectional Zener TVS family used to clamp voltage transients on power rails, signal lines, and communication buses. The single unidirectional channel means it protects against positive-going surges in one polarity — for AC or bidirectional protection a matched pair or different series would be needed. Surface-mount SMC package fits pick-and-place assembly lanes and reflow profiles standard in telecom, industrial control, and consumer electronics boards — no through-hole mounting required.