Microchip Technology MAPLAD36KP18AE3

Overview

MAPLAD36KP18AE3 from Microsemi is a unidirectional surface-mount transient voltage suppressor (TVS) designed for high-energy surge protection in aerospace and automotive power systems. It delivers 36,000 W peak pulse power at 10/1000 μs, features a 18 V reverse standoff voltage (VWM), clamps to ≤30.8 V at 1169 A peak impulse current, and exhibits 1.0 °C/W junction-to-case thermal resistance. It is qualified to AEC-Q101 and meets RTCA DO-160 Section 22 multi-stroke lightning requirements.

For engineers reviewing the MAPLAD36KP18AE3 datasheet, MAPLAD36KP18AE3 pinout, MAPLAD36KP18AE3 application, or MAPLAD36KP18AE3 equivalent, key selection criteria include its 18 V VWM rating, 30.8 V max clamping voltage at 1169 A, low-profile PLAD package with metal-base cathode, RoHS-compliant e3 termination, and suitability for secondary lightning protection per IEC 61000-4-5 with 42 Ω source impedance up to Class 5.

Technical Context

This TVS diode operates as a clamping device in parallel with protected circuitry, triggering at breakdown voltage (V(BR) = 20.0–22.1 V) to divert surge energy away from sensitive components. Its low RθJC (1.0 °C/W) enables effective heat transfer to a heatsink or PCB copper plane, supporting repeated surge events under ≤0.05% duty cycle.

The device complies with IEC 61000-4-2 (ESD), IEC 61000-4-4 (EFT), and IEC 61000-4-5 (lightning surge) standards, and is validated for pin-injection immunity per RTCA/DO-160F Waveform 4 (Level 4 up to 400 V) and Waveform 5A (Level 4 up to 78 V). Its unidirectional polarity and metal-base cathode configuration require correct PCB orientation during layout.

Key Specifications

Pinout & Package

MAPLAD36KP18AE3 uses the PLAD surface-mount package: void-free UL94V-0 epoxy body (12.32 × 10.54 × 5.08 mm), matte-tin (e3) RoHS-compliant terminations, and metal base acting as cathode terminal. Mounting requires recommended pad layout (A = 11.94 mm, B = 5.85 mm) for optimal thermal and mechanical reliability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ18A and V26MLA0603NH, MAPLAD36KP18AE3 provides 90× higher peak power, certified thermal performance for repeated surges, and documented compliance with aviation and automotive surge standards - making it the only option for mission-critical high-energy transient suppression.

Availability

MAPLAD36KP18AE3 is available at Aetrix Electronics and suitable for aerospace power distribution, automotive load dump protection, and industrial motor drive DC bus applications requiring stable component supply, long-lifecycle support, and traceable high-reliability sourcing.

Supply support for MAPLAD36KP18AE3 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, RF, and timing solutions for aerospace, defense, and industrial markets.

The MAPLAD36KP18AE3 belongs to Microsemi's PLAD-series high-power TVS family, engineered specifically for multi-stroke lightning protection and automotive load dump compliance in safety-critical systems.

FAQ

What is the clamping voltage of MAPLAD36KP18AE3 at its rated peak pulse current?

The MAPLAD36KP18AE3 has a maximum clamping voltage (VC) of 30.8 V when subjected to its rated peak impulse current of 1169 A under 10/1000 μs waveform conditions. This value is measured per standard test methods defined in the datasheet and ensures downstream circuitry remains within safe operating voltage limits during high-energy transients. The clamping performance is guaranteed across the full operating temperature range.

Is MAPLAD36KP18AE3 qualified for automotive applications?

Yes, MAPLAD36KP18AE3 is AEC-Q101 qualified and specifically designed for automotive load dump protection per ISO 7637-2 Pulse 5a. Its 18 V VWM rating aligns with 12 V battery systems, and its 36,000 W surge capability exceeds typical load dump energy requirements. The device also supports thermal management via its metal-base cathode, enabling robust mounting on engine-control-unit PCBs.

How does the PLAD package of MAPLAD36KP18AE3 improve thermal performance?

The PLAD package of MAPLAD36KP18AE3 features a metal base that serves as both the cathode terminal and primary thermal conduction path. With a junction-to-case thermal resistance of just 1.0 °C/W, it enables efficient heat transfer to PCB copper planes or external heatsinks. This design allows MAPLAD36KP18AE3 to sustain repeated 36 kW surges without thermal runaway-unachievable with standard SMD packages like SMA or SMC.

Does MAPLAD36KP18AE3 meet RTCA DO-160 lightning protection requirements?

Yes, MAPLAD36KP18AE3 is explicitly validated for RTCA DO-160 Section 22 multi-stroke lightning testing. Its 36,000 W peak pulse power rating, fast response (<100 ps), and low clamping voltage ensure compliance with Level 4 and Level 5 pin-injection immunity for Waveforms 4 and 5A. The device is widely deployed in avionics power supplies where DO-160 certification is mandatory.

What is the meaning of the 'E3' suffix in MAPLAD36KP18AE3?

The 'E3' suffix in MAPLAD36KP18AE3 indicates RoHS-compliant matte-tin plating per JEDEC J-STD-020B, with no lead or hazardous substances. This termination ensures reliable solderability, long-term intermetallic stability, and compatibility with lead-free reflow profiles. The 'E3' marking is laser-etched on the device body and corresponds to Microsemi's standardized RoHS-conformance designation.