What the 1500W peak pulse rating means for your BOM
The 1.5KE91CA: The 125 V clamping voltage at 12.2 A peak pulse current (10/1000 µs waveform) means a 77.8 V supply bus — common in 48 V telecom or 72 V industrial systems — gets clamped before the downstream DC-DC converter's input rating is exceeded. The 1500 W rating is the peak pulse power dissipation for an 8/20 µs or 10/1000 µs surge — the actual energy the part absorbs depends on the pulse duration.
Housed in a DO-201AA (DO-27) axial-leaded package, the 1.5KE91CA is a through-hole part suited for point-to-point wiring or PCB mounting where the lead bend radius and hole diameter match the DO-201 footprint. The bidirectional construction means a single device protects both polarities — no need for two diodes back-to-back on a bipolar line. The junction temperature limit of 175°C allows the device to absorb repeated surges in a 85°C ambient enclosure without derating the peak power below the 1500 W mark.
Active production — no lifecycle surprises
For a BOM that already qualified the DO-201 footprint, the active lifecycle means no board spin is required for the foreseeable future.