TransZorb® TVS in the 1.5SMC family
The 1.5SMC91CA-M3/9AT is a unidirectional bidirectional transient voltage suppressor — Vishay's TransZorb® family in the DO-214AB (SMC) surface-mount package.
What 1.5kW peak pulse means for surge handling
1500W peak pulse capacity in the 10/1000µs wave shape is the standard telecom and industrial surge waveform — it means the part survives a single 12A surge event without degradation, and the clamping voltage of 125V is what actually clamps across the line being protected. The 77.8V standoff rating defines the working voltage the circuit runs at continuously without the TVS conducting — the gap between 77.8V and 125V is the protection headroom. Junction temperature rating extends to 150°C, which gives margin in enclosed or thermally challenging environments. The -65°C low end covers cold-start and outdoor equipment — the die doesn't see damage at cold extreme the way some lower-rated parts do.