Obsolete automotive TVS — what the 1500W rating means for the BOM line
The 1.5KE220AHE3/51: Its 328V clamping voltage at 4.6A peak pulse current means a 185V nominal rail — typical for 180V DC bus or 120V AC rectified lines — is clamped before the transient exceeds the downstream semiconductor's breakdown.
Automotive qualification and temperature envelope
The 175°C maximum junction temperature (TJ) is the upper limit for the silicon die itself; the DO-201AA axial package's thermal impedance to the PCB copper area sets the practical derating above 25°C. At 1500W peak pulse, the device absorbs the transient energy within the pulse duration, but repetitive events require the average power to stay within the thermal budget.
EOL reality — sourcing an obsolete automotive TVS
Each lot is verified for date code and traceability against the original Vishay manufacturing marks — no pin-compatible successor from Vishay is documented, so a board-level replacement would require requalification of a functionally equivalent TVS in the same DO-201AA footprint.