600W peak pulse power — what it covers
The SMBJ85CE3/TR13: Rated for 600W peak pulse power per the 10/1000 µs waveform, this TVS clamps transients up to 3.9 A peak pulse current before the silicon gives out. That 600W number is the energy the die can absorb in a single pulse — enough for most industrial surge events on a 48 V or 85 V rail, but not a direct lightning hit. The scorch mark on a dead board tells you whether the TVS held or the downstream IC took the hit.
Bidirectional — one device for both polarities
A single bidirectional channel means the same part clamps positive and negative transients symmetrically. No need to orient the diode on the board — it works either way, which simplifies assembly and reduces polarity errors on the line.
Breakdown and clamping window
Reverse standoff is 85 V — the rail voltage the part sits across without conducting. Breakdown starts at 94.4 V minimum, and clamping maxes out at 151 V at the peak current. That 57 V window between standoff and clamp is the margin your downstream silicon has to survive. If the protected IC's abs-max is below 151 V, this part won't save it.
Active production — no end-of-life worry
Listed as Active by Microchip Technology. No NRND flag, no last-time-buy clock ticking. You can design this in today and expect to buy it next year without a board spin.
DO-214AA (SMB) — the common footprint
Surface-mount in the DO-214AA (SMB) package. Same footprint as the generic SMBJ series — if your BOM already has an SMBJ part, this drops in without a layout change.