Microchip Technology MAPLAD36KP28AE3

Overview

MAPLAD36KP28AE3 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, clamps at ≤46.4 V under 776 A peak impulse current, and features a 28 V reverse standoff voltage (VWM), 31.1–34.4 V breakdown voltage (V(BR)), and 1.0 °C/W junction-to-case thermal resistance. It is widely deployed in aircraft lightning protection per RTCA DO-160 Section 22.

For engineers reviewing the MAPLAD36KP28AE3 datasheet, MAPLAD36KP28AE3 pinout, MAPLAD36KP28AE3 application, or MAPLAD36KP28AE3 equivalent, key selection criteria include its 28 V VWM rating, bidirectional variant availability (MAPLAD36KP28CAE3), RoHS-compliant e3 plating, AEC-Q101 qualification, and IEC 61000-4-5 Class 4 compliance with 12 Ω source impedance.

Technical Context

This TVS diode operates as a clamping device in parallel with sensitive circuitry to divert high-current transients-such as lightning-induced surges or automotive load dump-away from downstream components. Its low R_θJC of 1.0 °C/W enables effective heat transfer to a heatsink, supporting repeated multi-stroke events per RTCA DO-160.

The device exhibits fast response (<5 ns clamping delay), meets IEC 61000-4-2 ESD (±30 kV contact), IEC 61000-4-4 EFT (4 kV), and provides pin-injection protection up to Level 5 for RTCA/DO-160F Waveform 4 (6.4/69 μs) and Waveform 5A (40/120 μs) at specified VWM ranges.

Key Specifications

Pinout & Package

MAPLAD36KP28AE3 uses a PLAD (Plastic Leaded Anode Down) surface-mount package with a metal base cathode terminal on the bottom surface. The device has two terminals: anode (top-side metallization) and cathode (exposed metal pad on underside). Mounting requires thermal pad layout per RF01216 Rev B (page 6) for optimal R_θJA control.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ28A and SMCJ28A, MAPLAD36KP28AE3 delivers 24× and 24× higher peak pulse power respectively, achieves 10× lower thermal resistance for stable multi-pulse operation, and carries formal AEC-Q101 and RTCA DO-160 certification-making it the only qualified solution for flight-critical and high-reliability automotive power rail protection.

Availability

MAPLAD36KP28AE3 is available at Aetrix Electronics and suitable for aircraft lightning protection, automotive load dump suppression, industrial motor drive I/O hardening, and railway signaling interface protection requiring stable component supply across extended production lifecycles.

Supply support for MAPLAD36KP28AE3 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 solutions for aerospace, defense, and industrial markets.

The MAPLAD36KP28AE3 belongs to Microsemi's PLAD-series high-power TVS family, engineered specifically for multi-stroke lightning and load-dump protection in safety-critical platforms where thermal stability, lot traceability, and standards compliance are non-negotiable.

FAQ

What is the clamping voltage of MAPLAD36KP28AE3 at its rated peak pulse current?

The MAPLAD36KP28AE3 has a maximum clamping voltage (V_C) of 46.4 V at 776 A peak pulse current (I_PP) under 10/1000 μs waveform conditions. This value is guaranteed per RF01216 Rev B datasheet Table on page 3 and defines the upper voltage limit imposed on protected circuitry during worst-case surge events. The low clamping ratio (V_C/V_WM ≈ 1.66) ensures effective protection of 28 V-rated downstream components.

Is MAPLAD36KP28AE3 qualified for automotive applications?

Yes, MAPLAD36KP28AE3 is explicitly tested and qualified to AEC-Q101 standards for stress testing of discrete semiconductors. Its construction-including wafer fabrication traceability, surge testing, and thermal design-supports deployment in automotive engine control, body electronics, and ADAS subsystems subject to ISO 7637-2 load dump and ISO 16750-2 supply voltage variation requirements.

Does MAPLAD36KP28AE3 require a heatsink for standard operation?

MAPLAD36KP28AE3 does not require an external heatsink for single-event surge suppression, but its 1.0 °C/W junction-to-case thermal resistance is optimized for mounting on a PCB thermal pad per RF01216 Rev B pad layout (page 6). For repetitive surge applications (e.g., >0.05% duty cycle), a heatsink or copper plane ≥10 cm² is recommended to maintain junction temperature below 150 °C and preserve long-term reliability.

What is the polarity configuration of MAPLAD36KP28AE3?

MAPLAD36KP28AE3 is a unidirectional TVS diode: the cathode is the exposed metal base on the underside of the PLAD package, and the anode is the top-side metallized terminal. Polarity marking is indicated on unidirectional versions only per datasheet Figure on page 6. This configuration allows it to clamp only positive transients relative to ground-ideal for DC power rail protection.

How does MAPLAD36KP28AE3 comply with RTCA DO-160 lightning standards?

MAPLAD36KP28AE3 is validated for RTCA DO-160 Section 22 multi-stroke lightning testing, delivering 36 kW peak pulse power at 10/1000 μs with <5 ns response. It supports Level 4 and Level 5 pin-injection protection per Waveforms 4 and 5A, and its thermal design enables cumulative heating management across sequential strokes-making it suitable for primary and secondary lightning protection in certified avionics equipment.