1.5 kW peak-pulse TVS Zener in DO-214AB SMC
The 1.5SMC68CAHM3/I is a bidirectional single-channel Transient Voltage Suppressor — a TransZorb®-type Zener — in the DO-214AB (SMC) surface-mount package. Bidirectional clamping means it suppresses both polarities of transient surge without requiring separate polarity-aware layout; a single device on a line protects against positive spikes and negative transients alike. Rated 1500 W peak pulse (10/1000 µs waveform), the 1.5SMC series is qualified to AEC-Q101, placing it in the automotive electronics stress-grade tier. Operating junction temperature runs to 150 °C, and the Tj range of -65 °C to 150 °C covers both cold-start and engine-bay ambient profiles.
Clamping ceiling and standoff: the three ratings that govern protection design
Reverse standoff voltage is 58.1 V typ — the working voltage below which the TVS presents high impedance and draws only leakage current. The part stays dormant in normal operation at this rail. Breakdown triggers at a minimum of 64.6 V, defining the threshold where conduction begins. For a protected rail, the downstream circuit must survive 92 V let-through for the duration of the surge event. Peak pulse current of 16.3 A (10/1000 µs) tells you the surge shape the part handles before self-heating exceeds the thermal limit. Matching the TVS Ipp rating to the expected surge magnitude in the telecom or automotive environment — lightning impulse, load dump, or inductive kick — is the primary selection gate.