Obsolete TVS — what it means for your BOM line
The 1.5KE170-E3/54: With a clamping voltage of 244V at 6.1A peak pulse current, it protects downstream circuitry from voltage transients up to that level.
Protection window and operating envelope
The reverse standoff voltage is 138V — the TVS draws negligible leakage below this threshold. Breakdown occurs between 153V (min) and the clamping limit of 244V at full peak pulse current. This 138V standoff suits 120VAC or 170VDC rail protection, where the TVS stays transparent during normal operation and clamps only during transients. The DO-201AA (DO-27) axial-lead package is through-hole mounted, rated for the full 1500W pulse without derating at 25°C lead temperature. The axial body clips into a standard 0.100-inch pitch hole pattern — no board spin needed to replace an existing DO-201 footprint.
Sourcing reality for an obsolete TransZorb
Each lot is traceable and verified against the original Vishay datasheet parameters. No pin-compatible successor is listed on the Vishay TransZorb line for this exact breakdown voltage in the DO-201 package. A functional replacement would require a different order code with the same 138V standoff and 1500W rating — confirm the clamping voltage and package match before committing a BOM change.