What the 1500W rating means on a TVS diode
The 1.5KE56-E3/73: That 1500W figure is the peak power the die can absorb in a single transient event — it does not mean continuous dissipation. For a sustained overvoltage, the junction temperature rise would exceed the 175°C TJ limit within milliseconds. The reverse standoff voltage is 45.4V, meaning the diode stays high-impedance below that level and does not load the rail.
Package and rework — DO-201AA axial
Through-hole DO-201AA (DO-27) axial package. Rework is straightforward — two solder points, no thermal pad to manage. Pin 1 is the cathode band; the anode is the opposite lead. That covers military and industrial environments — the die itself is the limiting factor, not the package or solder joint.
Lifecycle and sourcing — obsolete, no direct successor
Vishay lists the 1.5KE56-/73 as Obsolete. The TransZorb series has been superseded by newer TVS families, but no single pin-compatible drop-in replacement is documented. No second-source cross-reference is maintained by the original manufacturer.