Microchip Technology MPLAD18KP75CA

Overview

MPLAD18KP75CA 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, clamps at ≤121 V under 100 A peak impulse current, and features a 75 V reverse standoff voltage (VWM) with ±5% breakdown tolerance (83.3–92.1 V). It is qualified to AEC-Q101 and meets RTCA DO-160F Level 4 pin injection for Waveform 4.

For engineers reviewing the MPLAD18KP75CA datasheet, MPLAD18KP75CA pinout, MPLAD18KP75CA application, or MPLAD18KP75CA equivalent, key selection criteria include its bidirectional polarity, 75 V working voltage, 121 V max clamping at 100 A, IEC 61000-4-5 Class 1–5 secondary lightning compliance, and suitability for aircraft avionics, engine control units, and DC bus protection where multi-stroke surge resilience is critical.

Technical Context

This TVS diode employs an avalanche breakdown structure optimized for low clamping ratio and fast response (<5 ns), enabling effective suppression of fast-rising transients such as ESD (IEC 61000-4-2), EFT (IEC 61000-4-4), and lightning-induced surges (IEC 61000-4-5). Its bidirectional construction allows symmetrical clamping on both polarities without external circuit inversion.

The device uses a void-free thermosetting epoxy package with tin-plated terminals solderable per MIL-STD-750 Method 2026, and achieves 0.7 °C/W junction-to-case thermal resistance - critical for dissipating 18 kW pulses without thermal runaway when mounted on heatsinked PCBs per recommended pad layout.

Key Specifications

Pinout & Package

Package: Surface-mount PLAD (Plastic Leaded Anode/Cathode) with metal base cathode terminal. Dimensions: 12.32 × 10.54 × 5.08 mm (L × W × H), weight ≈ 1 g. Cathode is the metal base (bottom side); anode is top-side metallization.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ75CA and SMCJ75CA, the MPLAD18KP75CA provides 30× and 12× higher peak pulse power respectively, enabling certified multi-stroke lightning resilience in aerospace and heavy-duty automotive systems - a distinction critical for safety-critical bus protection where single-event robustness is insufficient.

Availability

MPLAD18KP75CA is available at Aetrix Electronics and suitable for aircraft avionics, automotive ECU power rails, and industrial DC bus protection requiring stable component supply, long-lifecycle assurance, and traceable high-reliability sourcing.

Supply support for MPLAD18KP75CA 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 components for aerospace, defense, and industrial markets.

The MPLAD18KP75CA belongs to Microsemi's PLAD-series high-power TVS family, engineered specifically for multi-stroke lightning protection in safety-critical platforms where standard TVS diodes fail under repeated 10/1000 μs surges.

FAQ

What is the clamping voltage of MPLAD18KP75CA at its rated peak pulse current?

The MPLAD18KP75CA has a maximum clamping voltage (VC) of 121 V at 100 A peak pulse current (IPP) under 10/1000 μs waveform conditions. This value is guaranteed across temperature and lot variations per the datasheet's electrical characteristics table and ensures downstream components see no more than 121 V during surge events. The MPLAD18KP75CA maintains this clamping performance even after multiple strokes when properly heatsinked.

Is MPLAD18KP75CA suitable for automotive applications?

Yes, the MPLAD18KP75CA is AEC-Q101 qualified and explicitly rated for automotive load dump protection per ISO 7637-2. Its 75 V VWM aligns with 24 V system architectures, and its 18,000 W PPP rating exceeds typical load dump energy requirements. The MPLAD18KP75CA also supports secondary lightning immunity per IEC 61000-4-5, making it appropriate for engine control units, battery management systems, and ADAS domain controllers.

Does MPLAD18KP75CA require a heatsink for reliable operation?

While the MPLAD18KP75CA can handle single 18 kW pulses without external heatsinking, sustained or multi-stroke operation requires thermal management. Its 0.7 °C/W RθJC demands direct attachment of the metal base to ≥25 cm² of 2 oz copper or an external heatsink to maintain junction temperature below 150 °C. The MPLAD18KP75CA's pad layout specification mandates a minimum 12.32 × 10.54 mm thermal pad for optimal performance - omitting this compromises surge endurance.

How does the CA suffix affect the functionality of MPLAD18KP75CA?

The "CA" suffix in MPLAD18KP75CA denotes bidirectional construction, meaning the device clamps symmetrically for both positive and negative transients - unlike unidirectional "A" variants that only protect one polarity. This makes the MPLAD18KP75CA ideal for AC-coupled lines, differential buses (e.g., RS-485), or floating systems where voltage reversal is possible. The cathode remains the metal base regardless of polarity mode.

What standards does MPLAD18KP75CA meet for aircraft applications?

The MPLAD18KP75CA is certified for RTCA DO-160F Section 22 lightning-induced transient testing, including Waveform 4 (6.4/69 μs) Level 4 and Waveform 5A (40/120 μs) Level 4 for 75 V devices. It also satisfies IEC 61000-4-5 secondary lightning protection up to Class 5 with 42 Ω source impedance. These qualifications are documented in Microsemi's RF01215 Rev B datasheet and make the MPLAD18KP75CA suitable for flight-critical avionics I/O protection.