What this TVS diode protects and how it clamps
The 1.5KE13ARL4 is a unidirectional Zener TVS diode from onsemi's Mosorb™ series, rated for 1500 W peak pulse power (10/1000 µs waveform). It clamps at 18.2 V maximum when the surge current reaches 82 A, and its reverse standoff voltage of 11.1 V means it stays off the 12 V rail under normal conditions. This is a through-hole axial part in a DO-201AD package — the same body as a 1.5KE series standard. The wide operating temperature range of -65°C to 175°C junction suits it for industrial and outdoor gear where ambient swings are severe.
Sourcing reality: obsolete, last-time-buy window closed
onsemi lists the 1.5KE13ARL4 as obsolete. No official successor is recorded. For a BOM line that still calls out this exact order code, the practical path is a last-time-buy from remaining distributor stock or a pin-compatible replacement from the same 1.5KE family. We can source and quote this part against your BOM quantity — the RFQ will confirm current availability and pricing at the time of order. No stock-holding claim is made here.
Key ratings that drive the fit decision
The 11.1 V standoff voltage defines the maximum continuous DC voltage the diode will not conduct — match it to your rail voltage with margin. The 18.2 V clamp is the voltage the protected circuitry must survive during a surge; if your downstream components are rated for 20 V or higher, this clamp gives headroom. Peak pulse current is 82 A. That 1500 W rating is the product of clamp voltage and peak current — it tells you the energy-handling capability for a single pulse. For repetitive surges, derate per the pulse derating curve in the datasheet. The DO-201AD axial package requires through-hole soldering — not a reflow process. Board layout must account for the lead spacing and the hole diameter for the axial leads.