Taiwan Semiconductor Corporation P4KE440

Overview

P4KE440 from Taiwan Semiconductor is a unidirectional 400W transient voltage suppressor (TVS) diode with a nominal breakdown voltage of 440V, working stand-off voltage of 356V, and clamping voltage of 631V at 0.66A peak pulse current. It features low leakage (<1μA), fast response (<1.0ps), and DO-41 packaging for overvoltage protection in high-voltage industrial power supplies.

For engineers reviewing the P4KE440 datasheet, P4KE440 pinout, P4KE440 application, or P4KE440 equivalent, key selection criteria include its 440V VBR min/max range (396–484V), 631V clamping performance at 10/1000μs waveform, AEC-Q101 qualification option (P4KE440H), and DO-204AL mechanical compatibility with legacy through-hole layouts.

Technical Context

The P4KE440 operates as a unidirectional avalanche diode, triggered when reverse voltage exceeds its 396–484V breakdown range at 1mA test current. Its 631V clamping voltage limits transient energy to protected circuits under standardized 10/1000μs surge conditions.

Designed for single-pulse suppression only, it delivers 400W peak power dissipation at 25°C with thermal derating above ambient, and exhibits <1μA reverse leakage at 356V working voltage - critical for low-power standby circuit integrity.

Key Specifications

Pinout & Package

DO-204AL (DO-41) axial-leaded package with cathode band marking; leads are pure tin-plated and solderable per J-STD-002. Mechanical dimensions comply with JEDEC DO-41 outline.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient voltage suppression applications.

Compared with P4KE440, the P4KE440A offers tighter breakdown control and lower clamping for improved protection margin, while the 1.5KE440A provides higher surge endurance at the cost of footprint and thermal redesign - neither is pin-compatible, requiring layout revision for substitution.

Availability

P4KE440 is available at Aetrix Electronics and suitable for industrial motor drives, high-voltage DC power supplies, and EV charging infrastructure requiring stable component supply with consistent DO-41 mechanical form factor and UL/ROHS compliance.

Supply support for P4KE440 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Taiwan Semiconductor Corporation (TSC) is a vertically integrated semiconductor manufacturer specializing in discrete power devices, TVS diodes, and rectifiers with global distribution and AEC-Q101 qualification capabilities.

The P4KE series was developed for cost-effective, high-reliability transient suppression in industrial, automotive, and lighting applications - emphasizing robust surge handling, low leakage, and standardized DO-41 packaging for broad design reuse.

FAQ

What is the exact breakdown voltage range for P4KE440?

The P4KE440 has a guaranteed breakdown voltage range of 396V to 484V at 1mA test current, measured per ANSI/IEEE C62.35 standards. This 20% tolerance reflects the inherent variability of silicon avalanche characteristics and ensures reliable triggering across temperature and production lots. The P4KE440 must be selected with this range in mind when designing voltage margins for protected circuits.

Is P4KE440 unidirectional or bidirectional?

P4KE440 is a unidirectional TVS diode, indicated by the absence of "CA" suffix and confirmed by its cathode-band marking and forward voltage specification (VF = 6.5V max). It conducts only in reverse breakdown mode and blocks forward current up to 3.5V - unlike bidirectional variants (e.g., P4KE440CA), which lack polarity marking and exhibit symmetrical clamping in both directions.

Does P4KE440 meet automotive qualification standards?

The base P4KE440 is not AEC-Q101 qualified; however, the P4KE440H variant - identified by the "H" suffix in the ordering code - is fully AEC-Q101 certified for automotive applications. This qualification includes stress testing for temperature cycling, humidity, and mechanical shock, making P4KE440H suitable for under-hood and EV charging systems where reliability under harsh conditions is mandatory.

What is the maximum clamping voltage of P4KE440 under standard test conditions?

The maximum clamping voltage of P4KE440 is 631V, measured at 0.66A peak pulse current using the standardized 10/1000μs double-exponential waveform. This value represents the upper limit of voltage seen by downstream components during worst-case surge events and is used in circuit protection analysis to verify that protected ICs remain within their absolute maximum ratings.

Can P4KE440 replace P4KE400 in an existing design?

P4KE440 can replace P4KE400 only if the system's maximum transient voltage exceeds 400V and the clamping margin allows 631V versus P4KE400's 574V. While both share DO-41 packaging and similar thermal characteristics, the higher V_BR of P4KE440 delays conduction - potentially exposing downstream components to longer overvoltage duration. Verify timing and energy absorption in the specific surge profile before substitution.