TransZorb bidirectional TVS — 1.5 kW peak pulse, 185 V standoff
The 1.5KE220CA-E3/51: The 1500 W rating means the device can absorb a single 10/1000 µs surge up to that power level without failing — a common benchmark for industrial and telecom secondary-side protection where the energy in a lightning-induced transient or inductive kickback must be shunted to ground.
Clamping parametrics and the 185 V rail decision
The 328 V clamp is the voltage the protected circuit must survive — downstream components rated for 350 V or higher have margin; a 250 V-rated capacitor would see its dielectric stressed beyond its maximum at the clamp voltage. The junction temperature derates the peak pulse power above 25°C per the standard TransZorb curve.
DO-201AA axial-lead package and board integration
The through-hole DO-201AA (DO-27) axial package mounts with leads formed to the board or inserted into a terminal block. The 1.5KE series footprint is standard across the TransZorb family — a 1.5KE220CA can be swapped for another 1.5KE voltage variant without layout changes. Supplied in Bulk packaging, suitable for hand-insertion or wave-solder assembly in low-to-medium volume production runs.
Last Buy status and sourcing posture
Vishay has placed the 1.5KE220CA-/51 into Last Buy status — the manufacturer's end-of-life notice is active, and remaining inventory is finite. Sourced through independent distribution channels against an RFQ.