28V standoff — what the clamping spec means
The 1.5SMCJ28CA: That 45.4 V is the figure that matters for downstream IC protection — it sits below the absolute-maximum ratings of most 24V-tolerant logic families. Rated 1.5 kW peak pulse power in the 10/1000 µs window — a shorter-duration spike at the same energy dumps less current, so the clamp stays lower; a slower front (1000 µs) pulls more current before the TVS limits it, and the clamp moves closer to its maximum. Know your worst-case transient shape before selecting a 1.5 kW part on a 24V line. Operating junction range runs from -50°C to 150°C — the 150°C ceiling gives thermal headroom in enclosed panels or near heat sources that would push a commercial-grade 85°C TVS into derating. The bidirectional configuration means it clamps both polarities on a single polarity rail, so polarity-sensitive circuits get two-direction protection from one device.
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