1500 W peak pulse in a DO-214AA footprint
The 1.5SMB51A: The 70.1 V clamping voltage at 21.7 A peak pulse current means this part clamps transients well below the typical 60 V bus rating of downstream DC-DC converters in telecom line cards.
Breakdown and standoff — the protection window
Reverse standoff voltage is 43.6 V, meaning the diode stays off below that level and does not leak onto the protected rail. Minimum breakdown voltage is 48.5 V, so the avalanche triggers reliably before the rail sees a transient above that threshold. The 1500 W peak pulse rating at 10/1000 µs gives a solid margin for secondary lightning surge protection in telecom equipment, where the GR-1089 intra-building surge typically peaks around 500 W per port.
Surface-mount storage and handling
Operating temperature range -65°C to 150°C junction covers telecom outdoor cabinets and central-office environments.