Transient protection envelope and what it guards
The 1.5KE350A-E3/51: With a breakdown voltage minimum of 333V and a clamping ceiling of 482V at 3.1A peak pulse current (10/1000µs waveform), it shunts overvoltage events before they reach downstream silicon — think industrial PSU outputs, motor drive DC buses, or telecom rectifiers where a 300V rail needs a hard voltage limit.
No power line protection (it's a standalone TVS, not a filtered suppressor), so it pairs with a fuse or PTC for overcurrent coordination.
Sourcing posture — Last Buy status
Vishay lists this part as Last Buy — meaning the manufacturer has announced end-of-life but still accepts final orders within a defined window. For BOM lines that already carry this MPN, the path is to source remaining inventory through independent distribution. Availability is lot-specific and confirmed at quote time against the required quantity.