Zener TVS for 376V rail protection
The STMicroelectronics P6KE440ARL is a 600W Zener transient voltage suppressor from the P6KE series, designed to clamp overvoltage transients on DC power rails and signal lines operating at up to 376V continuous. It is a unidirectional device in a DO-204AC (DO-15) axial-lead through-hole package, rated for general-purpose surge protection where a single channel is sufficient.
Voltage window and clamping behaviour
The reverse standoff voltage of 376V is the maximum DC or peak AC voltage the protected line can carry without the device conducting appreciably. Breakdown occurs at a minimum of 418V, and the clamping voltage is held to a maximum of 776V at the rated peak pulse current of 5.2A (8/20µs waveform). This clamping ratio — 776V at 5.2A versus a 376V standoff — is typical for a Zener TVS; the design margin between the protected circuit's absolute maximum rating and the clamping voltage must be at least 776V to avoid damage during a surge event.
Power handling and surge capability
Rated at 600W peak pulse power for a 10/1000µs waveform, the device can absorb substantial transient energy. The 5.2A peak pulse current (8/20µs) is the current the part can safely shunt while clamping at 776V. No power line protection feature is included — this is a basic TVS diode, not a filtered or coordinated protector. Capacitance is 350pF at 1MHz, which may affect high-speed signal lines; for data-line protection, a lower-capacitance TVS or a steering-diode array is preferred.
Package and assembly note
The DO-15 axial package requires through-hole mounting with 0.040-inch (1.0 mm) diameter holes on a 0.300-inch lead spacing. Wave soldering or hand soldering is typical; the leads are tin-plated and solderable per standard IPC J-STD-001 profiles.
Lifecycle and sourcing
Cut Tape (CT) is also available for prototype or low-volume builds.