Microchip Technology MPLAD18KP170CA

Overview

MPLAD18KP170CA from Microsemi is a bidirectional surface-mount transient voltage suppressor (TVS) designed for high-energy surge protection in aerospace, automotive, and industrial systems. It delivers 18,000 W peak pulse power at 10/1000 μs, clamps at ≤275 V under 100 A peak impulse current, and features a 170 V reverse standoff voltage (VWM) with ±5% breakdown tolerance (189–209 V). It is qualified to AEC-Q101 and meets RTCA DO-160F Level 4 pin injection for Waveform 4.

For engineers reviewing the MPLAD18KP170CA datasheet, MPLAD18KP170CA pinout, MPLAD18KP170CA application, or MPLAD18KP170CA equivalent, this device is selected for secondary lightning protection per IEC 61000-4-5 (42 Ω, 12 Ω, and 2 Ω source impedances), ESD/EFT immunity per IEC 61000-4-2/4-4, and high-reliability avionics load dump suppression where thermal resistance (RθJC = 0.7 °C/W) and low-profile mounting are critical.

Technical Context

The MPLAD18KP170CA employs an avalanche diode structure optimized for fast response (<5 ns clamping time) and repeatable multi-stroke surge handling. Its metal-base package enables direct thermal coupling to heatsinks, supporting junction-to-case thermal resistance of 0.7 °C/W and steady-state dissipation up to 71 W at TC = 100°C.

It operates as a bidirectional clamp across signal or power lines, with symmetrical breakdown (V(BR) = 189–209 V) and clamping voltage VC ≤ 275 V at IPP = 100 A. Compliance with RTCA DO-160F Waveform 4 (6.4/69 μs) and IEC 61000-4-5 Class 2–5 ensures suitability for aircraft secondary protection and industrial surge environments.

Key Specifications

Pinout & Package

Package: Surface-mount PLAD (Plastic Leaded Anode/Cathode) with metal baseplate for thermal conduction. Dimensions: 12.32 × 10.54 × 5.08 mm (L × W × H); weight ≈ 1 g; RoHS-compliant matte-tin plating; UL94V-0 epoxy body.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ170CA and V275LA20AP, the MPLAD18KP170CA uniquely combines 18 kW pulse handling, sub-5 ns response, DO-160F/IEC compliance, and metal-base thermal performance - making it irreplaceable in high-reliability aerospace and automotive power rail protection where single-point failure is unacceptable.

Availability

MPLAD18KP170CA is available at Aetrix Electronics and suitable for aircraft avionics, automotive power distribution, and industrial motor drive applications requiring stable component supply, long-term lifecycle support, and traceable high-reliability sourcing.

Supply support for MPLAD18KP170CA 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

Microsemi (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog, mixed-signal, and radiation-hardened components for aerospace, defense, and industrial markets.

The MPLAD18KP170CA belongs to Microsemi's PLAD-series high-power TVS family, engineered specifically for multi-stroke lightning protection in safety-critical platforms where thermal robustness, regulatory compliance, and long-term parametric stability are mandatory.

FAQ

What is the clamping voltage of MPLAD18KP170CA at its rated peak pulse current?

The MPLAD18KP170CA has a maximum clamping voltage (VC) of 275 V when subjected to a 100 A peak impulse current (IPP) under 10/1000 μs waveform conditions. This value is measured across the device terminals with the cathode mounted to a thermally optimized heatsink, ensuring consistent voltage limiting during high-energy transients encountered in aviation and automotive load dump scenarios.

Is MPLAD18KP170CA compliant with automotive reliability standards?

Yes, the MPLAD18KP170CA is qualified to AEC-Q101 for discrete semiconductors, including stress testing for temperature cycling, humidity bias, and surge robustness. Its wafer fabrication and assembly lot traceability further support PPAP documentation requirements for Tier 1 automotive suppliers integrating the device into power distribution modules or ADAS control units.

How does the metal baseplate of MPLAD18KP170CA improve thermal performance?

The metal baseplate of the MPLAD18KP170CA serves as both the cathode terminal and primary thermal conduction path, achieving a junction-to-case thermal resistance (RθJC) of just 0.7 °C/W. When soldered to a 2 oz. copper thermal pad or external heatsink, this enables sustained power dissipation up to 71 W at TC = 100°C - far exceeding standard SMD TVS devices limited by RθJA alone.

Can MPLAD18KP170CA be used for IEC 61000-4-5 Class 5 lightning protection?

No - the MPLAD18KP170CA is certified for IEC 61000-4-5 Class 1–4 under 42 Ω and 12 Ω source impedances, and Class 2–3 under 2 Ω. Class 5 requires higher energy handling beyond its 18 kW rating; for Class 5, Microsemi recommends cascaded protection using this device as secondary stage behind a higher-energy front-end suppressor.

What does the "CA" suffix indicate in MPLAD18KP170CA?

The "CA" suffix in MPLAD18KP170CA explicitly denotes bidirectional construction, meaning the device provides symmetrical clamping for both positive and negative transients. Unlike unidirectional variants (e.g., MPLAD18KP170A), the CA version has identical breakdown and clamping characteristics in either polarity - essential for protecting AC-coupled or floating differential signal paths.