Transient suppressor for 459 V DC rails
The 1.5KE540A-E3/54: Its 459 V reverse standoff voltage means it sits across a DC bus up to that level without conducting leakage, then clamps transients at 740 V max to protect downstream semiconductors. The 513 V minimum breakdown voltage gives a 54 V window between standoff and clamping onset — enough margin for a regulated 459 V rail with normal ripple, while still catching surges before they reach the 740 V clamp ceiling.
Peak current and thermal envelope
At the 740 V clamping voltage, the device handles 2.03 A of peak pulse current (Ipp) for the standard 10/1000 µs transient. The 1500 W rating is the product of clamp voltage and peak current — a common benchmark for comparing TVS diodes in this power class. Operating temperature spans -55 to 175 °C junction, covering military and industrial temperature grades. The wide range suits deployment in outdoor telecom rectifiers, motor drive DC links, and power supplies where ambient heat and self-heating both factor into derating.
Supplied in the DO-201AA / DO-27 axial-leaded package, a through-hole format with a 1.5KE supplier device code. The leaded body is compatible with existing board layouts using this footprint — no pad redesign needed for a drop-in replacement in a TVS socket position. The reel format suits automated insertion; the cut tape works for prototype or low-volume builds.
Active lifecycle — no obsolescence watch needed
The base product number is 1.5KE540; the -/54 suffix denotes the lead-free / RoHS-compliant finish and the specific packaging code. No pin-compatible second source is recorded in the Vishay TransZorb family for this exact voltage and power class.