Microchip Technology MAPLAD18KP120CA

Overview

MAPLAD18KP120CA 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, features a 120 V reverse standoff voltage (VWM), clamps to ≤193 V at 100 A peak impulse current (IPP), and exhibits <5 ns response time. It is qualified to AEC-Q101 and meets RTCA DO-160F Waveform 4 Level 4 and IEC 61000-4-5 Class 1–5 secondary lightning protection requirements.

For engineers reviewing the MAPLAD18KP120CA datasheet, MAPLAD18KP120CA pinout, MAPLAD18KP120CA application, or MAPLAD18KP120CA equivalent, this device is selected for high-reliability DC bus protection where multi-stroke lightning immunity, low thermal resistance (RθJC = 0.7 °C/W), and RoHS-compliant SMT packaging are critical design constraints.

Technical Context

The MAPLAD18KP120CA employs an avalanche diode structure optimized for fast transient suppression with sub-5 ns clamping response. Its metal-base package enables direct thermal coupling to PCB copper or heatsinks, achieving RθJC of 0.7 °C/W and supporting sustained operation up to +150 °C junction temperature.

It is rated for bidirectional operation with symmetric breakdown (V(BR) = 133–147 V @ I(BR)), maximum clamping voltage VC = 193 V at IPP = 100 A, and standby leakage ID ≤10 μA at VWM = 120 V. Compliance includes IEC 61000-4-2/4-4/4-5, RTCA DO-160F Waveforms 4 & 5A, and AEC-Q101 stress testing.

Key Specifications

Pinout & Package

MAPLAD18KP120CA uses a surface-mount PLAD package with two terminals: anode and cathode. The metal base serves as the cathode terminal and provides primary thermal path to PCB. Package dimensions: 12.32 × 10.54 × 5.08 mm (L × W × H), with void-free UL94V-0 epoxy body and matte-tin plating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAPLAD18KP120CA, SMAJ120CA offers compact size but sacrifices >97% peak power handling and aerospace qualification, while SM8S120CA matches power rating but lacks the metal-base thermal efficiency and certified lightning waveform performance required for flight-critical systems.

Availability

MAPLAD18KP120CA is available at Aetrix Electronics and suitable for aerospace avionics, automotive 48V architectures, industrial motor drives, and railway signaling systems requiring stable component supply, long-term lifecycle assurance, and traceable high-reliability sourcing.

Supply support for MAPLAD18KP120CA 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, RF, and timing solutions for aerospace, defense, and industrial markets.

The MAPLAD18KP120CA belongs to Microsemi's high-power PLAD TVS family, engineered specifically for mission-critical surge protection where multi-stroke lightning resilience, low thermal resistance, and regulatory compliance (DO-160, AEC-Q101, IEC 61000-4-5) are mandatory.

FAQ

What is the clamping voltage of MAPLAD18KP120CA at its rated peak pulse current?

The MAPLAD18KP120CA has a maximum clamping voltage (VC) of 193 V when subjected to a 100 A peak impulse current (IPP) under 10/1000 μs waveform conditions. This value is measured per Figure 3 in the RF01215 datasheet and ensures downstream components remain within safe operating voltage limits during surge events.

Is MAPLAD18KP120CA qualified for automotive applications?

Yes, MAPLAD18KP120CA is AEC-Q101 qualified, confirming its reliability for automotive under-hood and powertrain applications. It supports 48V system protection against load dump and ISO 7637-2 transients, with validated performance across -55 °C to +150 °C junction temperature range.

Does MAPLAD18KP120CA meet RTCA DO-160 lightning protection requirements?

Yes, MAPLAD18KP120CA is certified for RTCA DO-160F Section 22 lightning-induced transient protection, including Waveform 4 (6.4/69 μs) Level 4 up to 120 V standoff. Its bidirectional construction and metal-base thermal design ensure compliance across multi-stroke test sequences.

What is the thermal resistance from junction to case for MAPLAD18KP120CA?

The MAPLAD18KP120CA has a junction-to-case thermal resistance (RθJC) of 0.7 °C/W, enabling efficient heat transfer from the silicon die to the PCB copper or external heatsink. This value is confirmed in the "MAXIMUM RATINGS" table of RF01215 Rev B and is critical for sustaining high-power surge duty cycles.

How does the bidirectional configuration of MAPLAD18KP120CA affect its use in DC circuits?

The bidirectional configuration of MAPLAD18KP120CA allows it to protect floating or AC-coupled DC lines without polarity concerns - both terminals behave identically under reverse or forward surge conditions. In DC applications, it functions as a symmetrical clamp across the line and return, making it ideal for ungrounded buses or differential signaling interfaces.