Obsolete — plan a replacement before your next BOM run
If you have an existing stock or a last-time buy window, the part is a 1500W Zener TVS in a DO-201AD axial package. For new designs or replenishment, you will need a pin-compatible substitute — the 1.5KE68A (without the RL4 suffix) is the same die in a different packaging option and may be a drop-in, but verify the reel/tape quantity and lead form before committing.
What the 1500W rating means for your protection rail
This is a 1500W peak pulse power Zener TVS rated for a 10/1000 µs waveform. The 58.1V reverse standoff voltage means it will not conduct at normal 48V or 60V bus levels, but clamps at 92V when a surge hits. The breakdown voltage min is 64.6V — that is the knee where the device starts to avalanche. For a 48V nominal rail, this gives about 16V of headroom before the TVS turns on, which is typical for industrial and telecom supplies.
Package and mounting — through-hole axial, no rework surprises
DO-201AD axial package, through-hole mount. The leads are tin-plated copper; the body is molded epoxy. No exposed pad, no thermal vias to worry about — just a clean axial lead that bends into a 1.1 mm (0.043 in) diameter hole.
Sourcing this obsolete part — what to expect
Because the 1.5KE68ARL4 is Obsolete, standard distributor stock is depleted or very limited. If you have an existing stock, the part is still usable; just ensure your incoming inspection checks the date code and lead solderability. For a long-term production run, we recommend qualifying the 1.5KE68A or a similar 1500W axial Zener TVS from onsemi's Mosorb™ family.