1.5SMCJ33A_R1_00001 as a TVS clamp
The peak pulse current of 28.1A at that waveform sets the clamping current the diode must conduct without lifting the standoff voltage off the protected rail.
DO-214AB SMC package and sourcing posture
The part ships in the SMC (DO-214AB) surface-mount package on tape-and-reel or cut-tape — the wide copper pad under the body gives the thermal path needed to dissipate the 1500W pulse energy without exceeding the junction temperature limit. The datasheet thermal impedance curve governs how long a given pulse width can run before the die heats past 150°C. Lifecycle is Active per the manufacturer record.