Automotive grade and temperature range
The 1.5KE51AHE3/51: The TransZorb series uses an oxide-passivated die construction that holds leakage stable across the temperature sweep.
Through-hole package and hand-solder friendliness
Housed in a DO-201AA (DO-27) axial-lead package, the 1.5KE51AHE3/51 is easy to hand-solder into a through-hole board — no reflow profile needed, and the body stands up to a quick iron touch. The axial leads also suit point-to-point wiring in prototype or repair work.
Obsolete — sourcing through independent channels
Vishay lists this part as obsolete. For a new-design replacement, a functionally equivalent TVS in the same DO-201AA footprint with a 43.6 V standoff and 1500 W rating would need to be qualified against the original's clamping curve.