Taiwan Semiconductor Corporation P4KE350A

Overview

P4KE350A from Taiwan Semiconductor is a unidirectional 400W transient voltage suppressor (TVS) diode designed for primary overvoltage protection in DC power rails and signal lines. It features a 350V nominal breakdown voltage, 300V working stand-off voltage, clamps to ≤482V at 0.87A peak pulse current, and delivers sub-nanosecond response (<1.0ps from 0V to V_BR). It is widely used in industrial power supplies and automotive ECU input protection.

For engineers reviewing the P4KE350A datasheet, P4KE350A pinout, P4KE350A application, or P4KE350A equivalent, key selection criteria include its 300V V_WM, 482V clamping voltage at 0.87A, DO-41 package compatibility, AEC-Q101 qualification option (P4KE350AH), and low leakage (<1μA @ 300V).

Technical Context

The P4KE350A operates as a unidirectional avalanche diode, leveraging silicon PN-junction breakdown to clamp transients above its 332–368V V_BR range (tested at 1mA). Its 400W peak pulse power rating is defined per 10/1000μs waveform per ANSI/IEEE C62.35, with thermal derating above 25°C ambient.

It exhibits a temperature coefficient of 0.110%/°C for V_BR, enabling predictable voltage drift across –55°C to +175°C operating junction range. The device maintains <1μA reverse leakage at 300V (V_WM) and achieves clamping within 1.0ps - critical for protecting fast-switching MOSFET gates and microcontroller I/O pins.

Key Specifications

Pinout & Package

DO-204AL (DO-41) package: axial-leaded, cylindrical glass-passivated body with cathode band marking. Leads are pure tin-plated, solderable per J-STD-002; polarity is marked by cathode band (cathode = banded end).

Key Features

Applications

Equivalent & Alternatives

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

Compared with P4KE350A, SMAJ350A offers SMT compatibility at the cost of higher leakage and different footprint, while 1.5KE350A provides greater energy handling in a larger axial package with marginally slower response - both require layout or mechanical reassessment.

Availability

P4KE350A is available at Aetrix Electronics and suitable for industrial power input protection, automotive body control modules, telecom DC feeder systems, and renewable energy charge controller designs requiring stable component supply and long-term obsolescence management.

Supply support for P4KE350A 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 analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, specializing in power management, protection, and interface devices.

The P4KE series belongs to TSC's transient voltage suppressor product line, engineered for robust, cost-effective overvoltage protection in automotive, industrial, and telecom infrastructure applications where reliability under repetitive surge stress is critical.

FAQ

What is the clamping voltage of the P4KE350A under standard surge conditions?

The P4KE350A clamps to a maximum of 482 V when subjected to its rated 10/1000μs surge waveform at 0.87 A peak pulse current (I_PPM). This value is measured per ANSI/IEEE C62.35 and represents the upper limit of voltage seen by downstream components during transient events - a critical parameter for ensuring compatibility with 500V-rated capacitors or 3.3V/5V logic interfaces protected via series impedance.

Is the P4KE350A suitable for automotive applications?

Yes - the P4KE350A has an AEC-Q101 qualified variant (P4KE350AH) that undergoes rigorous stress testing including temperature cycling, high-temperature reverse bias, and humidity testing. While the base P4KE350A is not AEC-Q101 certified, its 175°C max junction temperature, low leakage, and robust DO-41 construction make it suitable for non-safety-critical automotive subsystems such as lighting control and infotainment power rails.

How does the P4KE350A differ from the P4KE350 (non-A) version?

The P4KE350A features tighter breakdown voltage tolerance: 332–368 V (±5%) versus 315–385 V (±10%) for the P4KE350. This results in more consistent clamping behavior and improved predictability in precision protection circuits. Both share identical package, power rating, and thermal specifications - the "A" suffix denotes enhanced V_BR uniformity, not functional or reliability differences.

Can the P4KE350A be used in bidirectional configurations?

No - the P4KE350A is unidirectional only, with a clearly marked cathode band. For bidirectional protection at 350V, the correct part is P4KE350CA (C = bidirectional, A = tight tolerance), which provides symmetrical clamping in both polarities and uses the same DO-41 package. Using P4KE350A in reverse-biased mode risks permanent breakdown due to lack of reverse avalanche design.

What is the maximum steady-state power dissipation for the P4KE350A?

The P4KE350A has a steady-state power dissipation (P_D) of 1 W at lead temperature (T_L) = 75°C with 9.5 mm lead lengths. This rating applies only to continuous DC or low-frequency AC stress - not transient events. In normal operation, leakage remains <1 μA at 300 V, resulting in negligible static power (<0.3 mW), making thermal management straightforward in typical through-hole mounting scenarios.