Microchip Technology MAPLAD18KP14A

Overview

MAPLAD18KP14A from Microsemi is a unidirectional surface-mount transient voltage suppressor (TVS) designed for high-energy surge protection in aerospace, automotive, and industrial power systems. It delivers 18,000 W peak pulse power at 10/1000 μs, clamps transients to ≤23.2 V at 776 A, and features a 14 V reverse standoff voltage (VWM), 15.6–17.2 V breakdown voltage (V(BR)), and 0.7 °C/W junction-to-case thermal resistance.

For engineers reviewing the MAPLAD18KP14A datasheet, MAPLAD18KP14A pinout, MAPLAD18KP14A application, or MAPLAD18KP14A equivalent, key selection criteria include its DO-160F Waveform 4 Level 4 compliance, IEC 61000-4-5 Class 1–5 secondary lightning protection capability, low-profile thermoset epoxy package with metal-base cathode, and suitability for high-reliability avionics power bus and load-dump protection.

Technical Context

The MAPLAD18KP14A operates as a silicon avalanche diode-based TVS, leveraging controlled breakdown behavior to clamp fast-rising transients while maintaining low leakage (<10 μA at 14 V). Its metal-base construction enables direct thermal coupling to heatsinks, supporting sustained surge handling under <0.05% duty cycle per Figure 2.

It meets RTCA/DO-160F Section 22 multi-stroke lightning requirements and provides pin-injection protection for Waveform 4 (6.4/69 μs) and Waveform 5A (40/120 μs), with derating guidance in MicroNote 132 and 134 for temperature and steady-state power叠加 effects.

Key Specifications

Pinout & Package

MAPLAD18KP14A uses a surface-mount plastic package with void-free UL94V-0 thermosetting epoxy body and tin-lead or RoHS-compliant matte-tin plating. The cathode is the metal base (underside), and the anode is the top-side metallized terminal - polarity is defined by physical orientation, not pin numbering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ14A and SMCJ14A, the MAPLAD18KP14A delivers 30× higher peak pulse power, certified DO-160F performance, and a metal-base thermal interface-making it the only viable option for flight-critical surge protection where thermal reliability and regulatory compliance are non-negotiable.

Availability

MAPLAD18KP14A is available at Aetrix Electronics and suitable for aircraft power distribution, automotive engine control, and industrial motor drive applications requiring stable component supply, long-term lifecycle support, and full traceability documentation.

Supply support for MAPLAD18KP14A 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 MAPLAD18KP14A belongs to Microsemi's PLAD family of high-power surface-mount TVS diodes, engineered specifically for DO-160F-compliant avionics and AEC-Q101-qualified automotive systems demanding multi-kilowatt surge resilience.

FAQ

What is the clamping voltage of MAPLAD18KP14A at its rated peak pulse current?

The MAPLAD18KP14A has a maximum clamping voltage (VC) of 23.2 V at 776 A peak pulse current (IPP) under 10/1000 μs waveform conditions. This value is measured per Figure 3 in RF01215 Rev B and ensures downstream circuitry remains within safe voltage limits during worst-case surge events. The MAPLAD18KP14A achieves this clamping performance while sustaining 18,000 W peak pulse power without thermal failure.

Is MAPLAD18KP14A certified for DO-160F Section 22 lightning testing?

Yes, the MAPLAD18KP14A is explicitly validated for RTCA/DO-160F Section 22 multi-stroke lightning protection, including Waveform 4 Level 4 (6.4/69 μs) and Waveform 5A Level 4 (40/120 μs). Documentation in RF01215 Rev B confirms its qualification across the full MPLAD18KP7.0A–200CA series, with temperature derating guidance provided in MicroNote 132. MAPLAD18KP14A meets these standards as a unidirectional device.

How does the metal-base construction of MAPLAD18KP14A improve thermal performance?

The metal base of MAPLAD18KP14A serves as both the cathode terminal and primary thermal conduction path, achieving a junction-to-case thermal resistance of just 0.7 °C/W. This allows efficient heat transfer to PCB copper pours or external heatsinks, minimizing junction temperature rise during 18,000 W surges. Unlike plastic-body TVS diodes, the MAPLAD18KP14A avoids thermal saturation under repeated transients-critical for avionics mission profiles.

What is the polarity configuration and mounting orientation for MAPLAD18KP14A?

The MAPLAD18KP14A is a unidirectional TVS with cathode on the metal base (bottom surface) and anode on the top metallized pad. Correct mounting requires the metal base to be soldered directly to a thermal pad or heatsink, with the top pad connected to the protected line. Polarity is physically defined-no silkscreen marking is needed. Reversing orientation prevents proper clamping and risks catastrophic failure during surge events. MAPLAD18KP14A must be mounted with base-down per package drawings in RF01215 Rev B.

Does MAPLAD18KP14A meet AEC-Q101 reliability standards?

Yes, MAPLAD18KP14A is tested in accordance with AEC-Q101 requirements for discrete semiconductors, as stated in RF01215 Rev B. It undergoes surge testing, high-temperature operating life, temperature cycling, and mechanical shock validation. The "A" suffix denotes unidirectional construction qualified to AEC-Q101, making MAPLAD18KP14A suitable for automotive engine control, transmission, and chassis applications where extended temperature operation and vibration resilience are mandatory.