Clamping and pulse ratings for the protection decision
The 1.5KE15A-E3/54: The 12.8 V reverse standoff voltage means the TVS stays transparent on a 12 V rail — leakage is negligible until the transient exceeds that threshold. Breakdown is guaranteed between 14.3 V and the clamping ceiling, so a 24 V supply bus is outside the safe operating window for this part; it is sized for nominal 12 V systems. The single unidirectional channel protects one signal or power line.
DO-201AA axial — through-hole mounting note
Housed in the DO-201AA (DO-27) axial-lead package, the 1.5KE15A-/54 is a through-hole device. The lead bend radius and hole diameter on the PCB must follow Vishay's recommended footprint to avoid stress cracks in the glass passivation — the same package used across the 1.5KE series, so a single board layout serves multiple voltage variants.
TransZorb series — what the name signals
Vishay markets this as a TransZorb® TVS, its proprietary designation for a silicon-avalanche diode optimized for repetitive surge clamping. The series is rated for general-purpose circuit protection — no power-line-specific rating, so it is suited for DC rail and signal-line transient suppression rather than AC mains clamping.