My Inquiry
My Account
Microchip Technology MPLAD18KP18A
- Part No.:
- MPLAD18KP18A
- Manufacturer:
- Microchip Technology
- Category:
- TVS Diodes
- Package:
- Nonstandard SMD
- Datasheet:
-
MPLAD18KP18A.pdf
- Description:
- TVS DIODE 18VWM 29.2VC PLAD
- Quantity:
- Payment:
- Shipping:
Inventory:3,167
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MPLAD18KP18A from Microsemi is a unidirectional surface-mount transient voltage suppressor (TVS) designed for high-energy surge protection in aerospace, automotive, and industrial power systems. It delivers 18,000 W peak pulse power at 10/1000 μs, clamps to ≤29.2 V at 617 A peak impulse current, and features a 18 V reverse standoff voltage (VWM) with 20.0–22.1 V breakdown range. 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 MPLAD18KP18A datasheet, MPLAD18KP18A pinout, MPLAD18KP18A application, or MPLAD18KP18A equivalent, this device is selected for high-reliability DC bus protection where low clamping voltage, fast response (<100 ps), and multi-stroke lightning resilience are critical - especially in avionics power distribution, 24 V/48 V vehicle electronics, and industrial PLC I/O modules.
Technical Context
The MPLAD18KP18A employs a planar junction silicon avalanche diode structure optimized for low thermal resistance (RθJC = 0.7 °C/W) and high cumulative surge endurance. Its metal-base cathode construction enables direct thermal coupling to heatsinks or PCB copper planes, supporting sustained energy dissipation under repetitive transients per RTCA DO-160 Section 22.
It operates as a crowbar-type protector: below 18 V it presents <10 μA standby leakage; above V(BR) min (20.0 V), it avalanches sharply to clamp transients within nanoseconds. The device is characterized for 10/1000 μs waveform compliance and supports derated PPP up to 71 W at TC = 100°C per Figure 3.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power (PPP) | 18,000 W @ 10/1000 μs - sustains single lightning strike energy without failure |
| Reverse Standoff Voltage (VWM) | 18 V - maximum continuous DC or peak AC voltage before conduction begins |
| Breakdown Voltage (V(BR)) | 20.0–22.1 V @ I(BR) - precise avalanche onset ensures predictable clamping margin |
| Max Clamping Voltage (VC) | 29.2 V @ 617 A IPP - limits protected circuit voltage stress during worst-case surge |
| Thermal Resistance (RθJC) | 0.7 °C/W - enables efficient heat transfer to external heatsink or large copper pour |
| Standby Current (ID) | ≤10 μA @ 18 V - negligible leakage in standby, preserving system efficiency |
| Response Time | <100 ps - sub-nanosecond turn-on prevents voltage overshoot on fast edges |
Pinout & Package
Package: Surface-mount PLAD (Plastic Leaded Anode Down) with metal base cathode terminal. Dimensions: 12.32 × 10.54 × 5.08 mm (L × W × H); weight ≈1 g. Cathode is the exposed metal bottom surface; anode is top-side metallization.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Top-side metallization) | Positive input terminal | Soldered to PCB trace; connects to line being protected (e.g., +24 V rail) |
| Cathode (Metal base / bottom) | Ground reference terminal | Must be soldered to large copper plane or heatsink for thermal and electrical return path |
Key Features
| Feature | Design Value |
|---|---|
| Low-profile SMT package | Enables high-density layout while maintaining 18 kW surge capability - no through-hole mounting required |
| AEC-Q101 qualification | Validated for automotive-grade reliability including temperature cycling, humidity bias, and mechanical shock |
| RTCA DO-160F Waveform 4 Level 4 compliance | Withstands 6.4/69 μs pin-injection transients up to 18 V VWM - certified for aircraft avionics interfaces |
| IEC 61000-4-5 Class 1–5 support (42 Ω source) | Meets full secondary lightning immunity across all severity classes without external series impedance |
| MIL-PRF-19500 upscreening option | Available with M, MA, MX, or MXL reliability screening for mission-critical aerospace deployments |
Applications
| Aerospace Power Distribution | Automotive Load Dump Protection |
|---|---|
Use Scenario: 28 V DC power bus in flight control computers subjected to DO-160 Section 22 multi-stroke lightning surges. IC Role / Device Role / Timing Role: Primary transient suppressor placed at bus entry point to limit voltage excursion to <30 V. Use Value: Prevents latch-up or damage to downstream DC-DC converters and FPGAs during repeated 18 kW transients. |
Use Scenario: 24 V battery-fed ECU power input exposed to ISO 7637-2 Load Dump pulses (up to 120 V, 400 ms). IC Role / Device Role / Timing Role: Fast-acting clamping device shunting surge energy to chassis ground before upstream regulator overvoltage. Use Value: Eliminates need for bulky TVS arrays; single MPLAD18KP18A handles full load dump energy without degradation. |
| Industrial PLC I/O Modules | Railway Signaling Power Supplies |
Use Scenario: 24 V digital input channels connected to field sensors in factory automation, subject to induced RFI and EFT bursts. IC Role / Device Role / Timing Role: Input-stage protector absorbing IEC 61000-4-4 EFT (4 kV) and ESD (±8 kV) events. Use Value: Maintains signal integrity and prevents false triggering of optocouplers or microcontrollers during EMC testing. |
Use Scenario: 110 V DC auxiliary power supply in train signaling cabinets exposed to traction-induced surges per EN 50121-3-2. IC Role / Device Role / Timing Role: Secondary surge limiter after primary MOV stage, providing precise clamping at 18 V reference level. Use Value: Enables tighter voltage tolerance on downstream DC-DC stages, improving overall system MTBF. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| Littelfuse SMAJ18A | Lower PPP (400 W), smaller SMA package, higher RθJA (110 °C/W), no DO-160 certification | Suitable only for consumer-grade or non-safety-critical 24 V circuits with infrequent transients | Select only if cost and board space outweigh aerospace/automotive reliability requirements |
| Vishay V18MLA0603 | MLV-based (not avalanche diode), slower response (~ns vs. ps), lower clamping ratio, no AEC-Q101 or DO-160 validation | Acceptable for basic ESD/EFT in telecom power supplies but not for lightning or load dump | Choose only for non-mission-critical applications where surge repetition rate is low and clamping precision is secondary |
Compared with SMAJ18A and V18MLA0603, the MPLAD18KP18A provides 45× higher peak power handling, sub-100 ps response, and formal qualification for aviation and automotive environments - making it the sole choice when multi-stroke lightning resilience and AEC-Q101 compliance are mandatory.
Availability
MPLAD18KP18A is available at Aetrix Electronics and suitable for aerospace power distribution, automotive load dump protection, and industrial PLC I/O modules requiring stable component supply across extended production lifecycles.
Supply support for MPLAD18KP18A 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 ICs for aerospace, defense, and industrial markets.
The MPLAD18KP18A belongs to Microsemi's PLAD-series high-power TVS family, engineered specifically for DO-160-compliant avionics and AEC-Q101-qualified automotive electronics demanding multi-kilowatt surge immunity in compact SMT form.
FAQ
What is the maximum clamping voltage of the MPLAD18KP18A at its rated peak pulse current?
The MPLAD18KP18A has a maximum clamping voltage (VC) of 29.2 V at 617 A peak pulse current (IPP) under 10/1000 μs waveform conditions. This value is guaranteed per the datasheet's Electrical Characteristics table and defines the upper voltage limit imposed on protected circuitry during worst-case surge events. The low clamping ratio (VC/VWM ≈ 1.62) ensures minimal overvoltage stress on downstream components.
Is the MPLAD18KP18A RoHS compliant, and what marking indicates compliance?
Yes, the MPLAD18KP18A is RoHS compliant when ordered with the "e3" suffix (e.g., MPLAD18KP18Ae3). Per the nomenclature guide in RF01215 Rev B, "e3" denotes annealed matte-tin plating meeting RoHS Directive 2011/65/EU. Non-RoHS versions use standard tin-lead plating and carry no e3 suffix. Both variants share identical electrical and thermal performance.
How is thermal management implemented for the MPLAD18KP18A in high-duty-cycle applications?
The MPLAD18KP18A relies on its metal-base cathode for thermal conduction: the exposed bottom surface must be soldered directly to a large copper pour or external heatsink. With RθJC = 0.7 °C/W, effective heat spreading reduces junction temperature rise. For steady-state power dissipation, derating curves (Figure 3) show PPP drops to 71 W at TC = 100°C - requiring thermal design that maintains case temperature within specification.
Does the MPLAD18KP18A meet IEC 61000-4-5 with 2 Ω source impedance, and if so, which classes?
No - per RF01215 Rev B, the MPLAD18KP18A supports IEC 61000-4-5 secondary lightning protection only at 42 Ω and 12 Ω source impedances (Classes 1–5 and 1–4 respectively). At 2 Ω source impedance, it is rated only for Class 2–3 per the document; Class 4 requires lower-voltage variants (e.g., MPLAD18KP5.0 to 64CA). This limitation reflects energy-handling trade-offs at very low source impedance.
Can the MPLAD18KP18A be used in bidirectional configurations, and how is polarity identified?
No - the MPLAD18KP18A is unidirectional only. Bidirectional variants carry the "CA" suffix (e.g., MPLAD18KP18CA). Polarity is defined by physical construction: the cathode is the metal base (bottom surface), and the anode is the top-side metallization. Correct orientation is critical; reverse mounting renders the device non-functional for surge suppression.
MPLAD18KP18A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Package/Case:
- Nonstandard SMD
- Series:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 18V
- Voltage - Breakdown (Min):
- 20V
- Voltage - Clamping (Max) @ Ipp:
- 29.2V
- Current - Peak Pulse (10/1000µs):
- 617A
- Power - Peak Pulse:
- 18000W (18kW)
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- Military
- Qualification:
- MIL-PRF-19500
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- PLAD
MPLAD18KP18A FAQ
1.How can I place an order for MPLAD18KP18A through Aetrix?
Please submit a Request for Quotation (RFQ) for MPLAD18KP18A on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MPLAD18KP18A reliable?
The price and inventory of MPLAD18KP18A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MPLAD18KP18A is usually 5 days.
3.What payment methods are accepted for MPLAD18KP18A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MPLAD18KP18A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MPLAD18KP18A?
MPLAD18KP18A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MPLAD18KP18A order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MPLAD18KP18A?
For technical support, including MPLAD18KP18A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MPLAD18KP18A requirements.
6.How does Aetrix verify that MPLAD18KP18A is sourced from the original manufacturer or authorized distributors?
All MPLAD18KP18A products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MPLAD18KP18A meets industry standards.
7.What is the process for return or replacement of MPLAD18KP18A?
All MPLAD18KP18A units undergo pre-shipment inspection (PSI). If there is an issue with MPLAD18KP18A, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MPLAD18KP18A part is unused and in its original packaging.
Return procedure for MPLAD18KP18A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MPLAD18KP18A Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
-
D5V0L1B2WS-7
Diodes Incorporated
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
