The 1.5KE91CAHE3/51: It comes in a through-hole DO-201AA (DO-27) axial package. The reverse standoff voltage is 77.8 V, and minimum breakdown voltage is 86.5 V. Operating temperature range spans -55°C to 175°C, covering the full automotive under-hood thermal profile without derating.
This part is marked Obsolete by Vishay. Sourcing is through independent distribution channels; availability and pricing are confirmed at RFQ against the BOM quantity. For new designs or long-term production, a functionally equivalent bidirectional TVS in the same 1500 W class with a similar standoff voltage should be evaluated. The DO-201AA footprint is common across many TVS families.