Microchip Technology MPLAD36KP78CA

Overview

MPLAD36KP78CA 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, clamps transients to ≤126 V at 286 A, and features a 78 V reverse standoff voltage (V_WM) with ±5% breakdown tolerance (86.7–95.8 V). It is qualified to AEC-Q101 and meets RTCA DO-160F Waveform 4 Level 4 and IEC 61000-4-5 Class 4 (42 Ω source) requirements.

For engineers reviewing the MPLAD36KP78CA datasheet, MPLAD36KP78CA pinout, MPLAD36KP78CA application, or MPLAD36KP78CA equivalent, this device is selected for secondary lightning protection, load dump suppression, and ESD/EFT hardening where low-profile SMT mounting, traceable high-reliability screening, and multi-stroke surge endurance are critical.

Technical Context

The MPLAD36KP78CA employs an avalanche diode structure optimized for fast response (<5 ns clamping rise time) and low thermal resistance (R_θJC = 1.0 °C/W), enabling efficient dissipation of repetitive 36 kW transients without cumulative heating. Its bidirectional construction allows symmetric clamping for AC-coupled or floating bus lines.

It operates across –55°C to +150°C junction temperature, supports IPC/JEDEC J-STD-020B Level 1 moisture sensitivity (no dry pack required), and is RoHS compliant (e3 plating). Surge testing per AEC-Q101 includes 100% lot-level 1000 A impulse validation.

Key Specifications

Pinout & Package

Package: PLAD (Plastic Low-Profile Anode-Cathode Dual) - void-free UL94V-0 epoxy body, metal base cathode termination, 12.32 × 10.54 × 5.08 mm (L×W×H), weight ~1.85 g. Mounting pad layout per RF01216 Rev B: 11.94 mm × 5.85 mm footprint with 2.44 mm solder mask opening.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ78CA and SMCJ78CA, the MPLAD36KP78CA uniquely combines 36 kW pulse handling, DO-160F Waveform 4 Level 4 validation, and 1.0 °C/W thermal resistance-enabling single-device protection in mission-critical aerospace and heavy-duty automotive systems where multi-stroke endurance and thermal stability are non-negotiable.

Availability

MPLAD36KP78CA is available at Aetrix Electronics and suitable for aircraft avionics, automotive 48 V power systems, and industrial motor drive designs requiring stable component supply, long-term lifecycle assurance, and full traceability for safety-critical deployments.

Supply support for MPLAD36KP78CA 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-tolerant ICs for aerospace, defense, and industrial markets.

The MPLAD36KP78CA belongs to Microsemi's PLAD-series high-power TVS family, engineered specifically for multi-stroke lightning and load dump protection in environments where standard TVS diodes fail due to thermal accumulation or insufficient energy rating.

FAQ

What is the clamping voltage of MPLAD36KP78CA at its rated peak pulse current?

The MPLAD36KP78CA has a maximum clamping voltage (V_C) of 126 V at 286 A peak pulse current under 10/1000 μs waveform conditions. This value is guaranteed across temperature and lifetime, and defines the upper voltage limit imposed on protected circuitry during worst-case surge events. The MPLAD36KP78CA maintains this clamping performance even after repeated multi-stroke surges when properly heatsinked.

Is MPLAD36KP78CA suitable for RTCA DO-160F Section 22 lightning protection?

Yes, the MPLAD36KP78CA is explicitly validated for RTCA DO-160F Section 22 multi-stroke lightning testing, including Waveform 4 (6.4/69 μs) Level 4 compliance. Its 36 kW rating, sub-5 ns response, and thermal design allow it to meet the stringent cumulative energy and repetition rate requirements of aircraft power and data systems. The MPLAD36KP78CA is referenced in Microsemi's RF01216 documentation for this exact use case.

Does MPLAD36KP78CA require a heatsink for continuous operation?

The MPLAD36KP78CA does not require an external heatsink for single-event surge suppression, but thermal management is essential for repetitive surges. With R_θJC = 1.0 °C/W and R_θJA = 50 °C/W, mounting the metal base to ≥25 cm² of 2 oz copper reduces junction temperature rise to <5°C during 1000-pulse sequences. For sustained duty cycles, a bolted heatsink is recommended. The MPLAD36KP78CA's metal-base package is designed for this direct thermal interface.

How does the bidirectional construction of MPLAD36KP78CA affect its circuit placement?

The bidirectional construction of MPLAD36KP78CA allows placement across any two nodes without polarity concern-ideal for AC-coupled interfaces, floating grounds, or differential buses like RS-485 or CAN FD. Unlike unidirectional TVS diodes, the MPLAD36KP78CA clamps both positive and negative transients symmetrically, eliminating risk of reverse-bias damage during negative-going surges. Its cathode is the metal base, making PCB layout straightforward.

What screening options are available for MPLAD36KP78CA in high-reliability programs?

The MPLAD36KP78CA supports optional upscreening per MIL-PRF-19500, including M, MA, MX, and MXL reliability levels with wafer lot traceability, 3σ standby current screening, and conformance inspections. These options are documented in Microsemi's Hirel Non-Hermetic Product Portfolio brochure and are commonly specified for avionics and military programs. The base MPLAD36KP78CA already meets AEC-Q101 and DO-160F requirements without upscreening.