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Home > Products > Discrete Semiconductor Products > Transistors > FETs, MOSFETs > FETs, MOSFETs

NXP Semiconductors BUK9E3R2-40E,127

Name: BUK9E3R2-40E,127
Brand: NXP Semiconductors
SKU: BUK9E3R2-40E,127
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BUK9E3R2-40E,127

Manufacturer:: NXP Semiconductors

Category:: FETs, MOSFETs

Package:: TO-262-3 Long Leads, I2PAK, TO-262AA

Datasheet:: BUK9E3R2-40E,127.pdf

Description:: MOSFET N-CH 40V 100A I2PAK

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Product details

Overview

BUK9E3R2-40E from Nexperia is an AEC-Q101-qualified N-channel TrenchMOS logic-level power MOSFET in I2PAK (SOT226) package, rated for 40 V V_DS, 100 A continuous drain current at T_mb = 25 °C, and 2.7 mΩ R_DS(on) at V_GS = 5 V and T_j = 25 °C. It serves as a high-current, thermally robust switching element in automotive 12 V systems including start-stop micro-hybrid control and transmission actuation.

For engineers reviewing the BUK9E3R2-40E datasheet, BUK9E3R2-40E pinout, BUK9E3R2-40E application, or BUK9E3R2-40E equivalent, key selection criteria include its true logic-level gate drive (V_GS(th) ≥ 0.5 V at 175 °C), 175 °C junction rating, repetitive avalanche capability, and mounting-base thermal resistance of 0.64 K/W - critical for high-reliability automotive power switching designs.

Technical Context

This device employs TrenchMOS technology to achieve low on-resistance with logic-level gate compatibility, enabling direct drive from 5 V microcontrollers without level-shifting. Its internal structure integrates a monolithic source-drain diode with 40 ns reverse recovery time and 47 nC recovered charge, supporting synchronous rectification and inductive load commutation.

The MOSFET features fully characterized dynamic parameters including 69.5 nC total gate charge, 25.8 nC gate-drain charge, and 6870–9150 pF input capacitance, allowing precise gate driver sizing and switching loss estimation. Thermal design is anchored to the mounting base (not ambient), with R_th(j-mb) = 0.64 K/W and derating curves confirming stable 100 A operation up to T_mb = 100 °C.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DS	40 V - Maximum blocking voltage compatible with 12 V automotive battery systems with load-dump margin.
I_D (continuous)	100 A at T_mb = 25 °C - Package-limited current capacity requiring heatsink interface for sustained operation.
R_DS(on)	2.7 mΩ (typ) at V_GS = 5 V, T_j = 25 °C - Enables <1 W conduction loss at 20 A, reducing thermal stress in high-duty-cycle switches.
V_GS(th)	≥ 0.5 V at T_j = 175 °C - Ensures reliable turn-on under worst-case hot-cranking conditions without gate overdrive.
E_AS	419 mJ (unclamped single-pulse) - Supports robust energy handling during inductive switching transients in solenoid/motor control.
R_th(j-mb)	0.64 K/W - Direct thermal path to PCB/heatsink enables compact thermal design with predictable junction temperature rise.
Q_G(tot)	69.5 nC - Determines gate driver peak current requirement (~1.4 A for 50 ns rise time with 5 Ω external resistor).

Pinout & Package

I2PAK (SOT226) plastic single-ended package with isolated mounting base electrically connected to the drain terminal; designed for surface-mount assembly with through-hole thermal anchoring via the metal base.

Pin/Terminal	Circuit Role	Design Meaning
1 (G)	Gate	Logic-level control input; requires ≤10 V drive; 100 nA leakage at 25 °C ensures low static power consumption.
2 (D)	Drain	Main high-side switching node; internally bonded to mounting base for low-inductance, high-current return path.
3 (S)	Source	Power ground reference; 7.5 nH internal inductance impacts switching speed and ringing in high-di/dt applications.
mb (Mounting Base)	Drain (electrically tied)	Thermal and electrical interface to heatsink/PCB copper; contributes 0.64 K/W to total thermal resistance.

Key Features

Feature	Design Value
AEC-Q101 qualification	Validated for automotive-grade reliability across temperature, humidity, and mechanical stress profiles per JESD47.
Repetitive avalanche rating	Enables safe operation under unclamped inductive switching without external snubbers in motor/solenoid drivers.
175 °C maximum junction temperature	Supports engine-bay placement and extended thermal margin in start-stop systems with minimal derating.
True logic-level gate threshold	V_GS(th) ≥ 0.5 V at 175 °C ensures turn-on even during hot cranking when supply rails dip below 5 V.
Low Q_GD/Q_G ratio	25.8 nC / 69.5 nC ≈ 37% - Improves Miller immunity and reduces risk of spurious turn-on in high-speed switching.

Applications

Start-Stop Micro-Hybrid Control	Transmission Solenoid Driver
Use Scenario: High-cycle switching of starter motor engagement/disengagement during engine auto-stop and restart events. IC Role / Device Role / Timing Role: Main power switch controlling battery-to-starter connection; must sustain 100 A pulses with <10 µs turn-off delay. Use Value: 781 A peak drain current rating and 114 ns turn-off delay enable fast, reliable starter actuation without thermal runaway.	Use Scenario: Precision PWM control of hydraulic solenoids in automatic transmission valve bodies. IC Role / Device Role / Timing Role: Low-loss, high-frequency switching element driving inductive loads at 1–10 kHz with tight duty-cycle resolution. Use Value: 2.7 mΩ R_DS(on) minimizes resistive heating during sustained 20–40 A coil currents, extending solenoid lifetime.
12 V Automotive Lighting Control	Electric Power Steering (EPS) Motor Phase Switch
Use Scenario: Overcurrent-protected headlamp and fog lamp switching in body control modules. IC Role / Device Role / Timing Role: Robust load switch with integrated avalanche energy handling for lamp filament inrush and open-circuit transients. Use Value: 419 mJ single-pulse avalanche energy absorbs lamp cold-resistance surges without failure or derating.	Use Scenario: Half-bridge upper-leg switch in 12 V EPS motor inverters requiring fast, low-loss commutation. IC Role / Device Role / Timing Role: High-current, low-R_DS(on) power stage component with minimized switching losses at 20 kHz PWM. Use Value: 69.5 nC total gate charge and 73 ns rise time support efficient high-frequency operation while limiting driver power dissipation.

Start-Stop Micro-Hybrid Control

Transmission Solenoid Driver

Use Scenario: High-cycle switching of starter motor engagement/disengagement during engine auto-stop and restart events.

IC Role / Device Role / Timing Role: Main power switch controlling battery-to-starter connection; must sustain 100 A pulses with <10 µs turn-off delay.

Use Value: 781 A peak drain current rating and 114 ns turn-off delay enable fast, reliable starter actuation without thermal runaway.

Use Scenario: Precision PWM control of hydraulic solenoids in automatic transmission valve bodies.

IC Role / Device Role / Timing Role: Low-loss, high-frequency switching element driving inductive loads at 1–10 kHz with tight duty-cycle resolution.

Use Value: 2.7 mΩ R_DS(on) minimizes resistive heating during sustained 20–40 A coil currents, extending solenoid lifetime.

12 V Automotive Lighting Control

Electric Power Steering (EPS) Motor Phase Switch

Use Scenario: Overcurrent-protected headlamp and fog lamp switching in body control modules.

IC Role / Device Role / Timing Role: Robust load switch with integrated avalanche energy handling for lamp filament inrush and open-circuit transients.

Use Value: 419 mJ single-pulse avalanche energy absorbs lamp cold-resistance surges without failure or derating.

Use Scenario: Half-bridge upper-leg switch in 12 V EPS motor inverters requiring fast, low-loss commutation.

IC Role / Device Role / Timing Role: High-current, low-R_DS(on) power stage component with minimized switching losses at 20 kHz PWM.

Use Value: 69.5 nC total gate charge and 73 ns rise time support efficient high-frequency operation while limiting driver power dissipation.

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel logic-level power MOSFET applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
STL220N4F7AG	40 V, 220 A, 1.7 mΩ @ 10 V; TO-220FP package; higher current but requires 10 V gate drive for full performance.	Not AEC-Q101 qualified; suitable for industrial/commercial 12 V systems but not automotive safety-critical functions.	Select only if gate drive is ≥10 V and AEC-Q101 compliance is not required; offers lower R_DS(on) but larger footprint and no mounting base thermal path.
IRF1404ZLPbF	40 V, 180 A, 3.8 mΩ @ 10 V; TO-220AB; non-logic-level (V_GS(th) = 2–4 V); no AEC-Q101 rating.	Lacks guaranteed turn-on at 5 V and 175 °C; unsuitable for hot-cranking or micro-hybrid environments.	Use only with dedicated gate driver or 10 V supply; avoid in automotive applications where logic-level compatibility and qualification are mandatory.

Compared with STL220N4F7AG and IRF1404ZLPbF, the BUK9E3R2-40E uniquely combines AEC-Q101 qualification, true 5 V logic-level operation at 175 °C, and a thermally optimized I2PAK mounting base - making it the only drop-in solution for production automotive 12 V power switching where reliability, thermal management, and gate drive simplicity are jointly constrained.

Availability

BUK9E3R2-40E is available at Aetrix Electronics and suitable for automotive start-stop systems, transmission control units, and 12 V lighting modules requiring stable component supply across multi-year vehicle production lifecycles.

Supply support for BUK9E3R2-40E 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

Nexperia is a global leader in discrete, logic, and PowerMOS semiconductors, spun off from NXP in 2017 and focused on high-volume, high-reliability components for automotive, industrial, and computing markets.

The BUK9E3R2-40E belongs to Nexperia's TrenchMOS automotive logic-level FET product line, engineered specifically for thermally demanding 12 V automotive power switching applications requiring AEC-Q101 compliance and robust avalanche performance.

FAQ

What is the maximum continuous drain current rating for BUK9E3R2-40E?

The BUK9E3R2-40E supports 100 A continuous drain current at mounting base temperature (T_mb) = 25 °C, limited by package thermal capacity. At T_mb = 100 °C, the rating remains 100 A due to its robust thermal design - confirmed in Figure 1 of the datasheet. This value applies only with adequate heatsinking to maintain T_mb within limits; actual system current must be validated against junction temperature using R_th(j-mb) = 0.64 K/W.

Is BUK9E3R2-40E suitable for 5 V microcontroller direct drive?

Yes, the BUK9E3R2-40E is a true logic-level MOSFET: its gate-source threshold voltage V_GS(th) is guaranteed ≥0.5 V at T_j = 175 °C, ensuring reliable turn-on with standard 5 V GPIO outputs even under worst-case hot-cranking conditions. At 25 °C, V_GS(th) ranges 1.4–2.1 V, and R_DS(on) drops to 2.7 mΩ at V_GS = 5 V - eliminating need for gate drivers in most automotive control applications.

Does BUK9E3R2-40E have avalanche capability?

Yes, the BUK9E3R2-40E is repetitively avalanche rated with a single-pulse unclamped avalanche energy E_AS of 419 mJ (ID = 100 A, V_sup ≤ 40 V). This ruggedness allows safe operation during inductive load switching transients - such as solenoid de-energization or motor commutation - without external snubber circuits, reducing bill-of-materials cost and board space in automotive power stages.

What is the thermal resistance from junction to mounting base for BUK9E3R2-40E?

The BUK9E3R2-40E has a maximum thermal resistance R_th(j-mb) of 0.64 K/W from junction to mounting base, measured under specified test conditions. This low value reflects its I2PAK (SOT226) package design with direct die-to-base thermal path. Engineers must interface the mounting base to a heatsink or thermal pad to realize this performance; ambient-based ratings (e.g., R_th(j-a) = 65 K/W) are not applicable for high-power operation.

Which automotive standards does BUK9E3R2-40E comply with?

The BUK9E3R2-40E is fully qualified to AEC-Q101 for discrete semiconductors, covering stress tests for temperature cycling, humidity, mechanical shock, and high-temperature operating life. It is designed and tested for use in high-performance automotive applications including start-stop systems, transmission control, and 12 V power distribution - meeting the reliability and quality requirements for Tier 1 automotive electronics suppliers.

BUK9E3R2-40E,127 Specifications

Product attributes: Attribute value

Manufacturer:: NXP Semiconductors

Series:: TrenchMOS™

Package/Case:: TO-262-3 Long Leads, I2PAK, TO-262AA

Packaging:: Tube

Product Status:: Obsolete

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 40 V

Current - Continuous Drain (Id) @ 25°C:: 100A (Tc)

Drive Voltage (Max Rds On, Min Rds On):: 5V, 10V

Rds On (Max) @ Id, Vgs:: 2.8mOhm @ 25A, 10V

Vgs(th) (Max) @ Id:: 2.1V @ 1mA

Gate Charge (Qg) (Max) @ Vgs:: 69.5 nC @ 5 V

Vgs (Max):: ±10V

Input Capacitance (Ciss) (Max) @ Vds:: 9150 pF @ 25 V

FET Feature:: -

Power Dissipation (Max):: 234W (Tc)

Operating Temperature:: -55°C ~ 175°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: I2PAK

BUK9E3R2-40E,127 FAQ

1.How can I place an order for BUK9E3R2-40E,127 through Aetrix?

Please submit a Request for Quotation (RFQ) for BUK9E3R2-40E,127 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 BUK9E3R2-40E,127 reliable?

The price and inventory of BUK9E3R2-40E,127 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BUK9E3R2-40E,127 is usually 5 days.

3.What payment methods are accepted for BUK9E3R2-40E,127?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BUK9E3R2-40E,127 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BUK9E3R2-40E,127?

BUK9E3R2-40E,127 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BUK9E3R2-40E,127 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 BUK9E3R2-40E,127?

For technical support, including BUK9E3R2-40E,127 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BUK9E3R2-40E,127 requirements.

6.How does Aetrix verify that BUK9E3R2-40E,127 is sourced from the original manufacturer or authorized distributors?

All BUK9E3R2-40E,127 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 BUK9E3R2-40E,127 meets industry standards.

7.What is the process for return or replacement of BUK9E3R2-40E,127?

All BUK9E3R2-40E,127 units undergo pre-shipment inspection (PSI). If there is an issue with BUK9E3R2-40E,127, 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 BUK9E3R2-40E,127 part is unused and in its original packaging.

Return procedure for BUK9E3R2-40E,127:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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