Transient suppression for 20 V rails
The SMCJ20A-13 is a Zener-type unidirectional TVS diode from Diodes Incorporated, designed to clamp transients on 20 V nominal supply rails. Breakdown occurs at a minimum of 22.2 V, clamping the voltage to 32.4 V maximum at the rated 46.3 A peak pulse current. This gives a clear margin above the 20 V reverse standoff — the rail sees no leakage at normal operating voltage, and the clamp engages only when the transient exceeds the 22.2 V threshold.
Package and board-fit
Housed in the DO-214AB (SMC) surface-mount package, the SMCJ20A-13 occupies a standard footprint with a large copper tab for heat sinking. The -55°C to +150°C junction temperature range covers industrial and under-hood automotive environments — the junction temperature rise from a single 1500 W pulse is brief, but repetitive pulsing requires the PCB copper area to keep the average junction below 150°C.