Surge protection window and clamping behaviour
The 1.5KE440CA-B: This protection window — from 376 V standoff to 602 V clamp — means the diode absorbs transients that exceed the normal line voltage without clipping the signal during normal operation, making it suited for 277 VAC or 300–350 VDC rail protection where the steady-state voltage stays below the standoff threshold.
Package, mounting, and thermal envelope
Housed in a DO-201AA (DO-27) axial-lead through-hole package, the 1.5KE440CA-B mounts directly into a PCB or terminal block with the leads forming the current path. The DO-201 body is the same footprint used across the 1.5KE series, so a single board layout serves multiple voltage variants in the family.