Zener TVS for 24V rail protection
Microchip SMBJ24CE3/TR13 is a bidirectional Zener TVS diode designed to clamp transients on a 24V nominal rail. Its 26.7V minimum breakdown voltage and 43V maximum clamping at 14A peak pulse current define the protection window — the rail sees no clamping below 26.7V, and the clamp holds at 43V worst-case during a 10/1000µs surge. Rated for 600W peak pulse power, this part handles moderate surge events on power inputs, relay coils, or signal lines in general-purpose industrial and telecom gear. The bidirectional configuration means a single device clamps both positive and negative transients — no polarity concern during rework or assembly.
Breakdown and clamping — what the numbers mean for your BOM
The 24V reverse standoff is the maximum DC or peak AC voltage the TVS will not conduct at — your 24V rail sits below this with margin. The 26.7V min breakdown is the threshold where the Zener starts to avalanche; below that, the part is effectively open. The 43V clamping voltage is the worst-case voltage the protected circuit sees during a 14A, 10/1000µs pulse — downstream components must survive that peak. The DO-214AA SMB package is a standard footprint — rework with hot air is routine; the body is large enough to hand-solder if needed, and the cathode band (absent on bidirectional) is replaced by a marking that reads the part number.
SMBJ24CE3/TR13 carries an active product status from Microchip Technology. Supplied in Tape & Reel for automated pick-and-place. The DO-214AA SMB package is MSL1 — no bake required before reflow if the shelf life is respected.