Microchip Technology MAPLAD36KP400A

Overview

MAPLAD36KP400A 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, clamps transients to ≤644 V at 56 A peak pulse current, and features a 400 V reverse standoff voltage (VWM) with 444–492 V breakdown voltage (V(BR)). It is qualified to AEC-Q101 and meets RTCA DO-160 Section 22 multi-stroke lightning requirements.

For engineers reviewing the MAPLAD36KP400A datasheet, MAPLAD36KP400A pinout, MAPLAD36KP400A application, or MAPLAD36KP400A equivalent, this device is selected for secondary lightning protection per IEC 61000-4-5 (42 Ω source), pin-injection immunity per RTCA/DO-160F Waveform 4 Level 4, and high-reliability load dump suppression where thermal resistance (RθJC = 1.0 °C/W) and low-profile SMT mounting are critical.

Technical Context

The MAPLAD36KP400A employs an avalanche diode structure optimized for fast response (<100 ps clamping delay) and high-energy dissipation in unidirectional configuration. Its metal-base cathode construction enables direct thermal coupling to PCB copper or heatsinks, supporting junction-to-case thermal resistance of 1.0 °C/W under defined mounting conditions.

It operates across –55 °C to +150 °C junction temperature range and is rated for 100% surge testing per lot. Electrical behavior is defined by strict V(BR) tolerance (±5%), low standby current (≤10 μA @ 400 V), and stable temperature coefficient (αV(BR) = 56 mV/°C), ensuring predictable clamping under thermal stress.

Key Specifications

Pinout & Package

MAPLAD36KP400A uses a surface-mount PLAD package with two terminals: anode and cathode. The cathode is the metal base (bottom side) of the device, requiring direct thermal contact with PCB copper pour or heatsink for optimal thermal performance. Package dimensions: 12.32 × 10.54 × 5.08 mm (L × W × H), RoHS-compliant matte-tin plating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAPLAD36KP400A, SMAJ400A lacks the thermal and energy-handling capability for mission-critical surge events, while SM8S400A provides partial electrical equivalence but omits traceable lot screening, DO-160 compliance evidence, and AEC-Q101 qualification-making MAPLAD36KP400A the sole choice for certified aerospace and automotive safety systems.

Availability

MAPLAD36KP400A is available at Aetrix Electronics and suitable for aerospace avionics, automotive ECU power protection, and industrial UPS DC input stages requiring stable component supply, long-term lifecycle support, and traceable high-reliability sourcing.

Supply support for MAPLAD36KP400A 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 power management solutions for aerospace, defense, and industrial markets.

The MAPLAD36KP400A belongs to Microsemi's high-power PLAD-series TVS family, engineered specifically for certified lightning and load dump protection in safety-critical platforms where thermal robustness, surge repeatability, and regulatory compliance are non-negotiable.

FAQ

What is the clamping voltage of MAPLAD36KP400A at its rated peak pulse current?

The MAPLAD36KP400A has a maximum clamping voltage (VC) of 644 V at 56 A peak pulse current (IPP), measured under standard 10/1000 μs waveform conditions. This value ensures downstream components see limited overvoltage during worst-case surge events. The clamping performance is validated across the full operating temperature range and is integral to its qualification for RTCA DO-160F Section 22 lightning testing. MAPLAD36KP400A maintains this specification with ≤5% unit-to-unit variation due to tight V(BR) tolerance control.

Is MAPLAD36KP400A suitable for bidirectional surge protection?

No, MAPLAD36KP400A is a unidirectional TVS device, indicated by the "A" suffix (versus "CA" for bidirectional versions like MAPLAD36KP400CA). Its cathode is the metal base, and it conducts only during reverse-biased overvoltage events. For AC or bipolar transient protection, the bidirectional MAPLAD36KP400CA must be used instead. Using MAPLAD36KP400A in bidirectional applications risks forward conduction and failure during positive transients. MAPLAD36KP400A is explicitly designed for DC power rail protection where polarity is fixed.

Does MAPLAD36KP400A require derating at elevated ambient temperatures?

Yes, MAPLAD36KP400A requires thermal derating above 25 °C ambient. Its steady-state power dissipation drops from 2.5 W at TA = 25 °C to zero at TA = 100 °C, following a linear derating curve. Peak pulse power also decreases with increasing junction temperature-per Figure 3 in RF01216 Rev B. Designers must use the published derating curves and ensure adequate copper area and thermal vias to maintain TJ ≤ 150 °C. MAPLAD36KP400A's RθJC = 1.0 °C/W assumes optimal mounting; actual board-level RθJA will determine real-world thermal margin.

What packaging options are available for MAPLAD36KP400A?

MAPLAD36KP400A is supplied in bulk or tape-and-reel format. Tape-and-reel packaging follows EIA-481-B standards and requires adding the "TR" suffix to the part number (e.g., MAPLAD36KP400ATR). Standard reel quantities are configurable per customer demand. The device weighs approximately 1.7–2.0 g and features RoHS-compliant matte-tin plating compatible with lead-free reflow profiles up to 260 °C for 10 seconds. No dry pack is required due to IPC/JEDEC J-STD-020B Level 1 moisture sensitivity classification.

How is MAPLAD36KP400A validated for aerospace applications?

MAPLAD36KP400A is validated for aerospace use through full compliance with RTCA DO-160F Section 22 (lightning-induced transient susceptibility), including multi-stroke testing at 36 kW. It is also AEC-Q101 qualified, with wafer and assembly lot traceability, 3σ standby current screening, and surge testing performed on every production lot. Microsemi's Hirel Non-Hermetic Product Portfolio supports optional MIL-PRF-19500 upscreening. MAPLAD36KP400A's qualification evidence-including test reports and screening data-is documented in MicroNote 132 and RF01216 Rev B, not inferred or generalized.