Microchip Technology MPLAD36KP18CA

Overview

MPLAD36KP18CA from Microsemi is a bidirectional surface-mount transient voltage suppressor (TVS) designed for high-energy surge protection in aerospace, automotive, and industrial power systems. It delivers 36 kW peak pulse power at 10/1000 μs, features a 18 V reverse standoff voltage (VWM), clamps transients to ≤30.8 V at 1169 A peak pulse current (IPP), and meets RTCA DO-160 Section 22 multi-stroke lightning requirements.

For engineers reviewing the MPLAD36KP18CA datasheet, MPLAD36KP18CA pinout, MPLAD36KP18CA application, or MPLAD36KP18CA equivalent, this device is selected for secondary lightning protection per IEC 61000-4-5 (with 2 Ω, 12 Ω, and 42 Ω source impedances), pin-injection immunity per RTCA/DO-160F Waveforms 4 and 5A, and ESD/EFT compliance per IEC 61000-4-2/4-4 - all in a low-profile thermoset epoxy package with metal-base thermal path.

Technical Context

This bidirectional TVS operates without polarity constraints, enabling symmetric clamping of positive and negative transients across its terminals. Its breakdown voltage range is 20.0–22.1 V at 5 mA test current, with a maximum clamping voltage of 30.8 V at 1169 A IPP under 10/1000 μs waveform - verified per MIL-STD-750 and AEC-Q101 test protocols.

Thermal design is optimized via direct metal-base mounting: junction-to-case thermal resistance is 1.0 °C/W, and junction-to-ambient is 50 °C/W on FR4 with recommended pad layout. It supports steady-state dissipation up to 2.5 W at 25°C ambient and is rated for operation from –55°C to +150°C junction temperature.

Key Specifications

Pinout & Package

Package: PLAD - surface-mount, void-free UL94V-0 thermosetting epoxy body with metal base (cathode terminal) for thermal and electrical grounding. Dimensions: 12.32 × 10.54 × 5.08 mm (L × W × H), weight ≈ 1.7–2.0 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ18CA and SMCJ18CA, the MPLAD36KP18CA provides 12× and 24× higher peak pulse power respectively, enabled by its metal-base thermal path and robust die construction - making it the sole option among the three qualified for aerospace lightning standards and automotive load dump.

Availability

MPLAD36KP18CA is available at Aetrix Electronics and suitable for aerospace avionics, automotive power electronics, and industrial motor drive designs requiring stable component supply, long-term lifecycle assurance, and traceable high-reliability sourcing.

Supply support for MPLAD36KP18CA 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, RF, and timing solutions for aerospace, defense, and industrial markets.

The MPLAD36KP18CA belongs to Microsemi's PLAD-series high-power TVS family, engineered specifically for multi-stroke lightning protection and high-energy transient suppression in safety-critical platforms.

FAQ

What is the clamping voltage of the MPLAD36KP18CA at its rated peak pulse current?

The MPLAD36KP18CA has a maximum clamping voltage (VC) of 30.8 V when subjected to its rated peak pulse current of 1169 A under the standard 10/1000 μs waveform. This value is measured at the device terminals and ensures downstream circuitry remains below critical overvoltage thresholds during surge events. The MPLAD36KP18CA maintains this clamping performance across its full operating temperature range.

Is the MPLAD36KP18CA qualified for automotive applications?

Yes, the MPLAD36KP18CA is tested in accordance with AEC-Q101 requirements and supports automotive load dump protection per ISO 7637-2. Its 18 V VWM and 30.8 V clamping voltage align with 24 V system architectures, and its metal-base thermal design handles sustained power dissipation in under-hood environments. The MPLAD36KP18CA is used in engine control units and ADAS power supplies where high-energy transient immunity is mandatory.

Does the MPLAD36KP18CA require a heatsink for reliable operation?

The MPLAD36KP18CA relies on its metal base for thermal conduction and achieves a low 1.0 °C/W junction-to-case resistance - but requires direct soldering to a minimum 10 cm² copper area or external heatsink for sustained surge duty. Without adequate copper or heatsinking, junction temperature rise exceeds safe limits during repeated 36 kW pulses. The MPLAD36KP18CA datasheet specifies pad layout dimensions to ensure optimal thermal performance on FR4 PCBs.

How does the MPLAD36KP18CA meet RTCA DO-160 Section 22 lightning requirements?

The MPLAD36KP18CA is validated for multi-stroke lightning testing per RTCA DO-160 Section 22 due to its 36 kW peak pulse power rating, sub-100 ps response time, and ability to withstand ≥1000 A impulses at 10/1000 μs. Its bidirectional construction and low clamping ratio (VC/VWM ≈ 1.71) ensure consistent protection across both polarities. The MPLAD36KP18CA is deployed in avionics power entry modules where cumulative heating and voltage overshoot must remain within strict airworthiness limits.

What is the meaning of the "CA" suffix in MPLAD36KP18CA?

The "CA" suffix in MPLAD36KP18CA denotes bidirectional polarity - indicating symmetrical clamping behavior for both positive and negative transients. Unlike unidirectional variants (e.g., MPLAD36KP18A), the CA version has no anode/cathode distinction in circuit function and is mounted without orientation constraints. This makes the MPLAD36KP18CA ideal for AC-coupled lines, differential buses, and any application where voltage polarity reversal is possible.