Clamping envelope for transient protection
The 1.5SMCJ24 is a unidirectional Zener-based TVS diode rated 24 V reverse standoff — the working rail the protected circuit sees in normal operation. For a 24 V rail this gives roughly 19 V of headroom to the clamping ceiling — enough to protect downstream ICs and connectors from surge events without firing on normal operating noise. The clamping voltage at 34.9 A is the figure that matters for Let-through voltage calculations; budget it against the absolute-maximum input of whatever sits behind it.
SMC package and thermal margins
The DO-214AB (SMC) package is the industry-standard SMT outline for 1.5–3 kW TVS diodes — widely second-sourced and compatible with standard hot-air or IR reflow profiles. The operating junction temperature extends to 150 °C, so the device tolerates elevated ambient without derating in most enclosed equipment. Solder joint reliability on the wide SMC leads benefits from a preheat ramp — the part is not hermetic, so a moisture bake before reflow (125 °C, 4–8 hours for an uncontrolled shelf) prevents popcorn delamination in production.