1500 W peak pulse in a bidirectional axial package
The 1.5KE39CAHE3/51: It clamps at 53.9 V maximum and handles a peak pulse current of 27.8 A, protecting downstream electronics from transients on 24 V or 28 V rails.
Bidirectional clamping for symmetrical protection
With a single bidirectional channel, this diode protects both polarities from a single device — no need to series two unidirectional parts. The reverse standoff voltage is 33.3 V typical, breakdown starts at 37.1 V minimum, and clamping is guaranteed at 53.9 V maximum. The 1500 W rating at 10/1000 µs means it absorbs high-energy transients like load dump or inductive kickback. For shorter pulses (8/20 µs), the peak power capability is higher, but the datasheet derating curve should be consulted for the exact pulse width.
Obsolete — sourced through independent channels
Vishay has marked the 1.5KE39CAHE3/51 as obsolete. No official successor is listed in the available records. The through-hole DO-201AA (DO-27) axial package is a standard footprint, so a pin-compatible replacement from another manufacturer may exist, but no direct cross-reference is provided here. Verify the electrical parameters (33.3 V standoff, 53.9 V clamp, 1500 W peak pulse) when selecting an alternative.