The 1500 W peak pulse rating (10/1000 µs waveform) defines the energy the 1.5SMCJ45CA can absorb without degradation — at 20.6 A peak current the clamping ceiling sits at 72.7 V maximum. In practice the clamping voltage tracks lower than that ceiling at a given peak current; the 72.7 V figure is the absolute maximum the protected node ever sees during a surge event. A downstream IC with a 40 V absolute-max rating is not safe behind this part — the standoff is 45 V (typ), so the TVS idles just above the protected rail in normal operation and transitions to clamp only when a transient exceeds the breakdown threshold.
The clamping chain — standoff, breakdown, clamp
Three voltage points define the selection chain: 45 V reverse standoff is where the TVS conducts negligible current in normal operation. Junction breakdown begins at 50 V minimum — the rated trigger threshold. When a surge drives 20.6 A through the device, the clamping voltage is held to 72.7 V maximum. The working peak reverse voltage (VWM) and the clamping voltage are separated by a wide margin, which gives the protected circuit breathing room against fast-rising transients without premature triggering on normal rail noise.
Junction temperature and DO-214AB board fit
Rated junction temperature runs to 150 °C, which gives margin in enclosed panels where ambient can reach 70–80 °C. The SMC (DO-214AB) package is the mid-size SMC footprint — compatible with standard surface-mount pick-and-place and reflow profiles. Thermal pad area on the PCB directly affects the device's steady-state current handling; the 20.6 A peak pulse rating is a short-duration figure — continuous operating current is governed by the thermal resistance to ambient and the maximum allowable junction temperature, not by the peak pulse spec.
Quoted to order through independent distribution against an RFQ; availability and lead time confirmed at quote time.