Zener TVS for 43.6V rails – 1500W pulse capability
The 1.5KE51ARL4 is an onsemi Mosorb™ Zener TVS diode rated for 1500W peak pulse power (10/1000µs waveform) with a reverse standoff voltage of 43.6V and a clamping voltage of 70.1V at 21.4A peak pulse current. Housed in a DO-201AD axial package, it operates from -65°C to 175°C junction temperature, making it suitable for high-temperature environments like industrial power supplies and automotive modules.
What the voltage ratings mean for your rail
The 43.6V reverse standoff is the maximum DC voltage the TVS can sit across without conducting — design it on a 36V or 42V bus with margin. Breakdown starts at 48.5V min, and clamping at 70.1V max limits the transient voltage seen by the downstream circuitry. With a 1500W peak pulse rating, this part handles substantial surge energy; the 21.4A peak pulse current at the 10/1000µs waveform gives a quick check against expected transient currents.
Lifecycle reality – obsolete, no direct successor
onsemi has marked the 1.5KE51ARL4 as Obsolete. No official successor part is listed in the product documentation.