1500W Zener TVS – protection window and package
The 1.5KE56ARL4 is a unidirectional Zener TVS diode from onsemi's Mosorb™ series, rated for 1500W peak pulse power (10/1000µs waveform). It clamps transients at 77V maximum, with a reverse standoff of 47.8V and a minimum breakdown of 53.2V. This window means the part stays transparent on a 48V rail and starts conducting just above that, protecting downstream silicon from surges up to 19.5A peak pulse current. Housed in a DO-201AD axial through-hole package, it handles the thermal pulse of a 1500W surge without failing — the axial leaded body conducts heat into the PCB copper and air.
onsemi lists the 1.5KE56ARL4 as Obsolete. For a BOM that already uses this part, the immediate decision is whether to secure last-time-buy inventory or qualify a drop-in alternative from the same 1.5KE family. The base product number 1.5KE covers a wide range of standoff voltages in the same DO-201AD package. A functionally equivalent replacement would share the same 47.8V standoff, 53.2V breakdown, and 77V clamp — for example, the 1.5KE56A (unidirectional, same ratings) is a common cross-shop candidate, though its suffix and packaging may differ. Confirm the exact voltage window and pulse rating before substituting.
Sourcing the 1.5KE56ARL4 – availability and RFQ
Because the part is obsolete, standard distributor stock is depleted. We source the 1.5KE56ARL4 through our multi-supplier network — including franchise, specialty, and open-market channels — and quote it per your BOM quantity and required date-code window.