1500 W TransZorb — a TVS that absorbed the surge
The 1.5KE180-E3/73: The 258 V maximum clamping voltage at 5.8 A peak pulse current defines the transient ceiling the protected bus sees — any surge below that energy is clamped before it reaches the downstream silicon.
Clamping window and standoff margin
Reverse standoff voltage is 146 V typ — the TVS draws negligible leakage below that threshold. Breakdown occurs between 162 V min, and the clamp hardens at 258 V max. The 16 V gap between standoff and breakdown gives the designer margin to absorb rail ripple without the TVS self-triggering on normal line noise.
Obsolete — sourcing through independent channels
Vishay has marked the 1.5KE180-/73 as obsolete. A board spin to a current-production TVS in the same DO-201AA footprint may be the more repeatable path for a new BOM.
Thermal and package envelope
Junction temperature range spans -55 °C to 175 °C — suited to high-reliability environments where the TVS sees repetitive surge events and the die temperature climbs above the 125 °C common for commercial-grade parts. The DO-201AA axial package (DO-27 equivalent) is a through-hole form factor, and the 1.5KE family suffix on the supplier device package matches the standard Vishay marking for this die size.