Microchip Technology MAPLAD36KP120AE3

Overview

MAPLAD36KP120AE3 from Microsemi is a unidirectional surface-mount transient voltage suppressor (TVS) designed for high-energy surge protection in aerospace and automotive systems. It delivers 36 kW peak pulse power at 10/1000 μs, features a 120 V reverse standoff voltage (VWM), clamps to ≤193 V at 187 A peak pulse current (IPP), and operates across –55°C to +150°C junction temperature. It is qualified to AEC-Q101 and meets RTCA DO-160 Section 22 multi-stroke lightning requirements.

For engineers reviewing the MAPLAD36KP120AE3 datasheet, MAPLAD36KP120AE3 pinout, MAPLAD36KP120AE3 application, or MAPLAD36KP120AE3 equivalent, key selection criteria include its 120 V VWM rating, 193 V max clamping voltage at 187 A, RoHS-compliant e3 plating, thermal resistance of 1.0 °C/W (junction-to-case), and suitability for secondary lightning protection per IEC 61000-4-5 with 12 Ω and 42 Ω source impedances.

Technical Context

This TVS diode uses an avalanche breakdown mechanism to divert high-energy transients away from sensitive circuitry. Its low R_θJC (1.0 °C/W) enables efficient heat transfer to a heatsink, supporting sustained surge handling under repetitive 0.05% duty cycle conditions. The device is optimized for unidirectional polarity with cathode on the metal baseplate, requiring proper PCB pad layout per Microsemi's recommended footprint.

It complies with IEC 61000-4-2 (ESD), IEC 61000-4-4 (EFT), and IEC 61000-4-5 (lightning surge) standards, and achieves RTCA DO-160F Waveform 4 Level 4 and Waveform 5A Level 4 protection up to 120 V VWM. Derating applies above 100°C case temperature per Figure 3.

Key Specifications

Pinout & Package

MAPLAD36KP120AE3 uses a thermally enhanced PLAD surface-mount package with a metal baseplate acting as the cathode terminal. The package measures 12.32 mm × 10.54 mm × 5.08 mm (L×W×H) and features tin-plated terminals compliant with MIL-STD-2026. Mounting requires the recommended FR4 pad layout (Ref: RF01216 Rev B, Page 6) for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ120A and 1.5KE120A, MAPLAD36KP120AE3 provides 60× higher peak pulse power, certified qualification for harsh environments, and a thermally optimized SMT package-making it the sole viable option for aerospace-grade and high-reliability automotive surge protection.

Availability

MAPLAD36KP120AE3 is available at Aetrix Electronics and suitable for aerospace power distribution, automotive load dump protection, and industrial motor drive inputs requiring stable component supply and long-term lifecycle support.

Supply support for MAPLAD36KP120AE3 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 solutions for aerospace, defense, and industrial markets.

The PLAD-series TVS diodes were developed specifically for high-energy transient suppression in mission-critical platforms where multi-stroke lightning resilience, thermal robustness, and qualification traceability are mandatory.

FAQ

What is the maximum clamping voltage of MAPLAD36KP120AE3 under standard test conditions?

The MAPLAD36KP120AE3 has a maximum clamping voltage (V_C) of 193 V when subjected to its rated peak pulse current of 187 A under the 10/1000 μs waveform. This value is measured per Figure 3 in the RF01216 datasheet and defines the upper voltage limit imposed on protected circuitry during surge events. Exceeding this clamping level risks damage to downstream components rated below 193 V absolute maximum.

Is MAPLAD36KP120AE3 suitable for bidirectional signal line protection?

No, MAPLAD36KP120AE3 is a unidirectional TVS diode, indicated by the "A" suffix (not "CA"). Its cathode is the metal baseplate, and it conducts only during negative transients relative to that terminal. For bidirectional protection on AC or differential lines, the MAPLAD36KP120CA variant must be used instead. Using MAPLAD36KP120AE3 on bidirectional lines leaves positive-going transients unprotected.

Does MAPLAD36KP120AE3 require a heatsink for reliable operation?

Yes-MAPLAD36KP120AE3 relies on thermal conduction through its metal baseplate. Its R_θJC of 1.0 °C/W assumes direct attachment to a heatsink or large copper plane per the recommended pad layout in RF01216 Rev B. Without adequate thermal sinking, junction temperature can exceed 150°C during repetitive surges, leading to parametric shift or failure. Derating curves in Figure 3 mandate reduced PPP above 100°C case temperature.

What qualifications does MAPLAD36KP120AE3 hold for automotive use?

MAPLAD36KP120AE3 is qualified to AEC-Q101 for stress testing including temperature cycling, humidity bias HAST, and mechanical shock. It also meets RTCA DO-160F Section 22 for multi-stroke lightning-making it suitable for automotive applications requiring DO-160 compliance, such as EV battery management systems and ADAS domain controllers. Its e3 RoHS plating supports lead-free manufacturing.

How does the "E3" suffix in MAPLAD36KP120AE3 affect assembly?

The "E3" suffix indicates RoHS-compliant matte-tin plating per J-STD-002 and MIL-STD-2026, enabling compatibility with standard lead-free reflow profiles (peak 260°C for 10 s). Unlike legacy SnPb terminations, E3 plating eliminates intermetallic growth concerns and ensures solder joint reliability under thermal cycling. No special flux or preheat is required beyond standard Class 3 IPC guidelines.