What this Zener TVS diode does and where it fits
The 1.5KE10AG is a unidirectional Zener TVS diode from onsemi's Mosorb™ series, designed to clamp transient overvoltages on a DC rail. Its 8.55V reverse standoff voltage means it stays off below that level, then avalanches at a minimum of 9.5V to shunt the surge. With a peak pulse power rating of 1500W and a clamping voltage of 14.5V maximum, it protects downstream circuitry from lightning-induced transients, inductive load switching, and ESD events in general-purpose industrial and telecom equipment. The DO-201AD axial package is through-hole mountable, making it a straightforward replacement on legacy boards.
Key ratings and what they mean for your BOM
The 1500W peak pulse power is rated for a 10/1000µs waveform — the standard telecom surge. The 103A peak pulse current at that waveform tells you the part can handle a heavy surge, but the clamping voltage of 14.5V is the number that matters for the protected device: if your load can't survive 14.5V, you need a lower-clamp part. The operating temperature range of -65°C to 175°C covers extreme environments from outdoor enclosures to engine bays, though derating above 25°C is expected.
Sourcing reality: obsolete status and what to do
The 1.5KE10AG is marked obsolete by onsemi. The base product number 1.5KE covers a family of voltage variants; a pin-compatible alternative within the same 1.5KE family (e.g., 1.5KE10A) may be available if the 'G' suffix (lead-free / RoHS) is not a hard requirement. We can source the part against an RFQ — confirm your quantity and we'll check open-market availability.