Microchip Technology MAPLAD18KP20AE3

Overview

MAPLAD18KP20AE3 from Microsemi is a unidirectional 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 a 20 V reverse standoff voltage (VWM), clamps to ≤32.4 V at 556 A peak current, and exhibits 0.7 °C/W junction-to-case thermal resistance for efficient heat dissipation in lightning and load-dump protection circuits.

For engineers reviewing the MAPLAD18KP20AE3 datasheet, MAPLAD18KP20AE3 pinout, MAPLAD18KP20AE3 application, or MAPLAD18KP20AE3 equivalent, key selection criteria include its DO-160F Waveform 4 Level 4 compliance, IEC 61000-4-5 Class 1–5 secondary lightning capability with 42 Ω source impedance, RoHS-compliant e3 plating, and metal-base cathode configuration requiring bottom-side thermal mounting.

Technical Context

This TVS diode operates as a clamping device in parallel with sensitive circuitry, activating above its 20 V standoff threshold to divert transients via avalanche breakdown. Its low RθJC (0.7 °C/W) enables direct thermal coupling to PCB copper or heatsinks, supporting multi-stroke RTCA DO-160 Section 22 compliance under ≤0.05% duty cycle conditions.

It meets AEC-Q101 stress testing requirements and supports both unidirectional surge suppression and ESD/EFT protection per IEC 61000-4-2/4-4. The device's 1 g mass and void-free UL94V-0 epoxy package are optimized for high-reliability surface-mount assembly on FR4 boards using recommended pad layout per RF01215 Rev B.

Key Specifications

Pinout & Package

MAPLAD18KP20AE3 uses a surface-mount plastic package with metal base cathode termination. The cathode is the exposed metal underside of the device body; the anode is the top-side metallized terminal. Package dimensions: 12.32 × 10.54 × 5.08 mm (L × W × H), with recommended FR4 pad layout per RF01215 Rev B.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ20A and SMCJ20A, MAPLAD18KP20AE3 provides 30× and 12× higher peak pulse power respectively, along with certified DO-160F Waveform 4 Level 4 performance, AEC-Q101 qualification, and 0.7 °C/W thermal resistance - making it uniquely suited for mission-critical aerospace and automotive surge protection where reliability and multi-stroke endurance are mandatory.

Availability

MAPLAD18KP20AE3 is available at Aetrix Electronics and suitable for aerospace avionics, automotive ECMs, and industrial motor drives requiring stable component supply with long-term lifecycle assurance and traceable sourcing.

Supply support for MAPLAD18KP20AE3 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 Corporation (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 PLAD family, including MAPLAD18KP20AE3, was engineered specifically for high-energy transient suppression in safety-critical platforms where DO-160, AEC-Q101, and IEC 61000-4-5 compliance are mandatory design requirements.

FAQ

What is the clamping voltage of MAPLAD18KP20AE3 at its rated peak pulse current?

The clamping voltage VC of MAPLAD18KP20AE3 is guaranteed ≤32.4 V at 556 A peak pulse current (IPP) under 10/1000 μs waveform conditions. This value is measured per Figure 3 in RF01215 Rev B and defines the maximum voltage imposed on protected circuitry during worst-case surge events. MAPLAD18KP20AE3 maintains this clamping performance across its full operating temperature range (-55 °C to +150 °C) when properly mounted to thermal mass.

Does MAPLAD18KP20AE3 require special PCB layout considerations for thermal management?

Yes - MAPLAD18KP20AE3 relies on its metal base cathode for thermal conduction, so the PCB must include a large, thermally robust copper pour (minimum 250 mm² recommended) directly beneath the device, connected via multiple thermal vias to internal ground planes. Per RF01215 Rev B, failure to implement the specified pad layout reduces RθJA from 50 °C/W to >100 °C/W, risking thermal runaway during repeated surges. MAPLAD18KP20AE3 must not be used without verified thermal mounting.

Is MAPLAD18KP20AE3 certified for RTCA DO-160F Section 22 lightning testing?

Yes - MAPLAD18KP20AE3 is explicitly listed in RF01215 Rev B as meeting RTCA DO-160F Section 22 multi-stroke lightning requirements, including Waveform 4 (6.4/69 μs) Level 4 compliance at 25 °C. Its 18,000 W PPP rating and low RθJC enable sustained performance across multiple strokes with ≤0.05% duty factor, satisfying aircraft-level surge resilience mandates that standard TVS diodes cannot achieve.

How does the e3 suffix in MAPLAD18KP20AE3 affect its assembly process?

The e3 suffix indicates RoHS-compliant matte-tin plating per J-STD-020B, enabling compatibility with lead-free reflow profiles up to 260 °C for 10 seconds. Unlike legacy SnPb terminations, MAPLAD18KP20AE3's e3 finish eliminates intermetallic formation risks during high-temperature assembly and supports IPC-A-610 Class 3 acceptability. No special flux or preheat adjustments are required beyond standard Pb-free SMT guidelines.

Can MAPLAD18KP20AE3 be used in bidirectional configurations?

No - MAPLAD18KP20AE3 is unidirectional (denoted by "A" suffix); bidirectional variants carry "CA" (e.g., MAPLAD18KP20CA). Using MAPLAD18KP20AE3 in AC or differential signal paths will result in forward conduction during negative half-cycles, causing catastrophic failure. For bidirectional protection, select the CA version, which features symmetrical breakdown in both polarities and identical 18 kW PPP rating.