Microchip Technology MAPLAD18KP18CAE3

Overview

MAPLAD18KP18CAE3 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, features 18 V reverse standoff voltage (VWM), clamps to ≤29.2 V at 617 A IPP, and meets RTCA DO-160 Section 22 multi-stroke lightning requirements.

For engineers reviewing the MAPLAD18KP18CAE3 datasheet, MAPLAD18KP18CAE3 pinout, MAPLAD18KP18CAE3 application, or MAPLAD18KP18CAE3 equivalent, key selection criteria include bidirectional polarity, 18 V VWM compatibility with 15–18 V nominal bus systems, IEC 61000-4-5 Class 1–5 secondary lightning protection capability, and thermal resistance of 0.7 °C/W junction-to-case for high-reliability PCB-mounted surge suppression.

Technical Context

This TVS diode operates as a clamping device in parallel with protected circuitry, activating when transient voltage exceeds its breakdown threshold (20.0–22.1 V). Its low RθJC (0.7 °C/W) enables effective heat transfer to the PCB copper plane or heatsink under repetitive surge conditions.

Designed for compliance with RTCA DO-160F Waveform 4 (Level 4) and Waveform 5A (Level 4), it supports pin-injection immunity testing in avionics systems. Bidirectional construction ensures symmetric clamping for AC-coupled or floating signal lines without polarity sensitivity.

Key Specifications

Pinout & Package

MAPLAD18KP18CAE3 uses a surface-mount PLAD package with metal base cathode (bidirectional configuration has symmetrical terminals). The metal base serves as both thermal conduction path and electrical terminal; polarity is non-directional due to bidirectional design.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ18CA and SMCJ18CA, MAPLAD18KP18CAE3 provides 12× and 12× higher peak pulse power respectively, validated clamping performance under RTCA DO-160F Waveform 4/5A, and a thermally optimized PLAD package enabling reliable multi-stroke operation in mission-critical systems.

Availability

MAPLAD18KP18CAE3 is available at Aetrix Electronics and suitable for aerospace avionics, automotive power electronics, and industrial motor control systems requiring stable component supply with long-term lifecycle assurance.

Supply support for MAPLAD18KP18CAE3 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 ICs for aerospace, defense, and industrial markets.

The MAPLAD series belongs to Microsemi's high-power surface-mount TVS portfolio, engineered specifically for DO-160-compliant lightning protection and automotive load dump suppression in safety-critical platforms.

FAQ

What is the clamping voltage of MAPLAD18KP18CAE3 at its rated peak pulse current?

The MAPLAD18KP18CAE3 exhibits a maximum clamping voltage (VC) of 29.2 V when subjected to its rated peak pulse current (IPP) of 617 A under 10/1000 μs waveform conditions. This value is guaranteed per the manufacturer's electrical characteristics table and defines the upper voltage limit imposed on protected circuitry during worst-case surge events. The low clamping ratio (VC/VWM ≈ 1.62) ensures robust protection margin for 18 V nominal systems.

Is MAPLAD18KP18CAE3 certified for RTCA DO-160 lightning testing?

Yes, MAPLAD18KP18CAE3 is explicitly validated for RTCA DO-160F Section 22 multi-stroke lightning testing. It meets Level 4 pin injection immunity for Waveform 4 (6.4/69 μs) and Waveform 5A (40/120 μs) at 25 °C, as documented in Microsemi Application Note RF01215 Rev B. This certification applies directly to the MAPLAD18KP18CAE3 variant and supports its use in certified avionics hardware without additional qualification.

How does the PLAD package of MAPLAD18KP18CAE3 improve thermal performance compared to standard SMC packages?

The PLAD package of MAPLAD18KP18CAE3 achieves a junction-to-case thermal resistance (RθJC) of just 0.7 °C/W - over 5× lower than typical SMC packages (~3.5–4.0 °C/W). This is accomplished via a void-free epoxy body bonded directly to a large metal base that serves as both electrical terminal and thermal interface. When mounted per the recommended pad layout on FR4, MAPLAD18KP18CAE3 sustains higher average power and survives repetitive surges better than conventional alternatives.

Does MAPLAD18KP18CAE3 meet IEC 61000-4-5 for industrial surge immunity?

Yes, MAPLAD18KP18CAE3 is qualified for IEC 61000-4-5 secondary lightning protection across multiple source impedances: Class 1–5 with 42 Ω, Class 1–4 with 12 Ω, and Class 2–3 with 2 Ω. These ratings are confirmed in the manufacturer's datasheet RF01215 Rev B and apply specifically to the MAPLAD18KP18CAE3 model. Its 18 kW rating ensures compliance even at the highest test levels (e.g., 4 kV Class 4).

What is the significance of the "CA" and "E3" suffixes in MAPLAD18KP18CAE3?

The "CA" suffix in MAPLAD18KP18CAE3 denotes bidirectional polarity, confirming symmetrical clamping behavior for AC or floating signal lines. The "E3" suffix indicates RoHS-compliant matte-tin plating on terminals, per IPC/JEDEC J-STD-020B moisture sensitivity Level 1 - meaning no dry-pack baking is required prior to reflow. Both suffixes are integral to the official Microsemi part numbering system and define core electrical and compliance attributes of the MAPLAD18KP18CAE3 device.