The 1.5KE22A-TP: Breakdown occurs at 20.9 V minimum, so the diode stays out of conduction below that threshold and only shunts when the transient exceeds the normal operating range.
DO-201AE axial — board-fit and thermal note
Through-hole DO-201AE package (same as 1.5KE series industry standard) with axial leads — the body sits above the board, and the lead length sets the thermal resistance. The operating junction range is -55°C to 175°C, covering the full industrial temperature envelope including cold-crank and high-ambient scenarios.
Active production — sourcing posture
Marked as Active by Micro Commercial Co.