Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

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

Nexperia USA Inc. BUK9Y1R9-40HX

Name: BUK9Y1R9-40HX
Brand: Nexperia USA Inc.
SKU: BUK9Y1R9-40HX
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: BUK9Y1R9-40HX

Manufacturer:: Nexperia USA Inc.

Category:: FETs, MOSFETs

Package:: -

Datasheet:: BUK9Y1R9-40HX.pdf

Description:: BUK9Y1R9-40H/SOT669/LFPAK

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:6,388

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

BUK9Y1R9-40HX from Nexperia is an AEC-Q101 qualified N-channel logic-level MOSFET with 40 V V_DS, 1.9 mΩ R_DS(on) at V_GS = 10 V and T_j = 25 °C, housed in LFPAK56 (SOT669) package. It delivers 120 A continuous drain current at T_mb = 25 °C and supports ultra-high-performance power switching in thermally demanding automotive environments up to 175 °C junction temperature.

For engineers reviewing the BUK9Y1R9-40HX datasheet, BUK9Y1R9-40HX pinout, BUK9Y1R9-40HX application, or BUK9Y1R9-40HX equivalent, this device is selected for high-current 12 V automotive load switching where low conduction loss, robust avalanche capability, and board-level reliability under thermal cycling are critical design requirements.

Technical Context

This MOSFET employs Trench 9 Superjunction technology, enabling reduced cell pitch for higher power density and lower R_DS(on) within the same LFPAK56 footprint. Its tight V_GS(th) range (1.35–2.05 V typ at 25 °C) ensures consistent turn-on behavior across temperature and simplifies parallel operation.

The LFPAK56 package integrates a copper clip for enhanced current spreading and reduced R_th(j-mb) (0.5–0.69 K/W), while gull-wing leads provide mechanical stress absorption during thermal cycling and support AOI-based solder inspection without x-ray. The source-drain diode exhibits soft reverse recovery (S = 0.85) and 26.8 nC recovered charge at 25 °C.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DS	40 V - Maximum drain-source blocking voltage for 12 V automotive system protection
R_DS(on)	1.9 mΩ max at V_GS = 10 V, I_D = 25 A, T_j = 25 °C - Enables <1.2 W conduction loss at 50 A
I_D (cont)	120 A at T_mb = 25 °C - Validated continuous current rating limited by PCB thermal design
E_AS	108 mJ non-repetitive avalanche energy - Supports unclamped inductive switching in solenoid/motor control
R_th(j-mb)	0.5 K/W typical - Enables efficient heat transfer to heatsink or copper plane via mounting base
V_GS(th)	1.35–2.05 V typ at 25 °C - Ensures reliable turn-on with 3.3 V/5 V logic-level gate drivers
Q_GD	7.3–14.6 nC at V_GS = 4.5 V - Low gate-drain charge improves switching efficiency and dV/dt immunity

Pinout & Package

LFPAK56 (SOT669) is a 4-terminal surface-mount plastic package with exposed copper mounting base connected to drain. It features gull-wing leads for mechanical reliability and visual solder inspection.

Pin/Terminal	Circuit Role	Design Meaning
1, 2, 3	Source (S)	Three parallel source terminals reduce source inductance and improve current sharing in high-di/dt switching
4	Gate (G)	Single gate input with 0.32–2 Ω internal gate resistance - compatible with standard MOSFET drivers without external gate resistor
Mounting base	Drain (D)	Exposed copper pad electrically and thermally connected to drain - serves as primary heat path and high-current return path

Key Features

Feature	Design Value
Trench 9 Superjunction architecture	Enables 1.9 mΩ R_DS(on) in LFPAK56 footprint - 30% lower on-resistance than prior-generation TrenchMOS at same size
AEC-Q101 qualification & 175 °C rating	Validated for automotive under-hood applications including start-stop micro-hybrid systems with extended thermal endurance
LFPAK copper clip construction	Reduces R_th(j-mb) by ~40% vs. standard QFN - increases maximum sustainable current by improving thermal headroom
Tight V_GS(th) distribution (1.35–2.05 V)	Supports stable paralleling of ≥3 devices without current imbalance - critical for high-power lamp/motor drivers
Soft-recovery source-drain diode (S = 0.85)	Minimizes voltage overshoot and EMI during freewheeling in inductive loads - reduces snubber component count

Applications

Motor Control in Start-Stop Systems

Lamp and Solenoid Load Switching

Use Scenario: Controlling starter motor engagement and disengagement in 12 V micro-hybrid vehicles during engine restart cycles.

IC Role / Device Role / Timing Role: High-side power switch handling 80–100 A peak currents with <100 ns switching transitions and full avalanche energy absorption.

Use Value: 108 mJ single-pulse avalanche rating prevents failure during inductive kickback from starter coil; 175 °C rating ensures operation during prolonged hot-soak conditions.

Use Scenario: PWM dimming and on/off control of LED headlamps and HVAC actuators in modern automotive lighting and comfort modules.

IC Role / Device Role / Timing Role: Low-R_DS(on) N-channel switch placed in low-side configuration with fast 20.5 ns fall time and minimal gate charge.

Use Value: 1.9 mΩ R_DS(on) limits conduction loss to <0.5 W at 50 A, reducing thermal derating and enabling compact PCB layout.

Transmission Control Valve Drivers

Ultra-High-Performance Power Distribution

Use Scenario: Driving electro-hydraulic solenoid valves in automatic transmission control units requiring precise current regulation and fault tolerance.

IC Role / Device Role / Timing Role: Robust power switch with tight V_GS(th) and high SOA - operates reliably across -40 °C to 150 °C ambient with no gate driver derating.

Use Value: 0.85 softness factor and 26.8 nC Q_r ensure low-voltage overshoot during diode commutation, protecting downstream sensors and MCU I/O.

Use Scenario: Centralized power distribution unit (PDU) managing multiple high-current loads (e.g., seat heaters, rear window defrosters) in next-gen vehicle architectures.

IC Role / Device Role / Timing Role: Primary load switch with 120 A continuous rating and 600 A pulsed capability - used with current-sense amplifiers for real-time diagnostics.

Use Value: LFPAK56 mounting base provides direct thermal interface to aluminum chassis - enables >90% of rated current without external heatsink at 40 °C ambient.

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel automotive power switching applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
STL220N4F7AG	40 V, 2.2 mΩ R_DS(on), PowerFLAT 5x6 package, 100 A I_D, no AEC-Q101 documentation publicly available	Lower current rating and unverified automotive qualification - suitable only for industrial-grade 12 V systems	Select when cost sensitivity outweighs AEC-Q101 compliance and thermal margin is sufficient
ON Semiconductor NTMFS4C09NT1G	40 V, 1.8 mΩ R_DS(on), SO-8FL package, 115 A I_D, AEC-Q101 qualified, R_th(j-mb) = 0.75 K/W	Higher thermal resistance limits sustained current in high-ambient designs - requires larger copper area for equivalent cooling	Select when existing SO-8FL footprint reuse is mandatory and peak pulse performance is prioritized over continuous thermal capability

Compared with STL220N4F7AG, BUK9Y1R9-40HX offers guaranteed AEC-Q101 compliance and superior thermal performance; versus NTMFS4C09NT1G, it delivers 25% lower R_th(j-mb) and higher continuous current capacity in identical board space - critical for start-stop and transmission control where thermal cycling endurance is non-negotiable.

Availability

BUK9Y1R9-40HX is available at Aetrix Electronics and suitable for automotive power distribution, start-stop micro-hybrid systems, and transmission control modules requiring stable component supply across multi-year production lifecycles.

Supply support for BUK9Y1R9-40HX 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 semiconductor expert focused on essential efficiency technologies, delivering high-performance discrete, logic, and MOSFET solutions for automotive, industrial, and consumer markets.

BUK9Y1R9-40HX belongs to Nexperia's LFPAK56 automotive-qualified logic-level MOSFET family, engineered specifically for high-current, thermally constrained 12 V automotive switching applications demanding AEC-Q101 reliability and low R_DS(on).

FAQ

Is BUK9Y1R9-40HX pin-compatible with other LFPAK56 MOSFETs?

Yes - BUK9Y1R9-40HX uses the standard SOT669 footprint with pins 1–3 as source, pin 4 as gate, and mounting base as drain. All Nexperia LFPAK56 MOSFETs share identical land pattern dimensions, thermal pad layout, and lead geometry per Figure 17 of the datasheet, enabling drop-in replacement within the same voltage/current class.

What is the maximum recommended gate drive voltage?

The absolute maximum V_GS is ±20 V per Table 5, but the device is characterized and optimized for 4.5 V and 10 V logic-level drive. Operation above 12 V provides diminishing R_DS(on) improvement and increases gate oxide stress - Nexperia recommends 10 V for full performance and long-term reliability in automotive applications.

Can BUK9Y1R9-40HX be used in synchronous rectification?

No - BUK9Y1R9-40HX is not specified or characterized for synchronous rectification. Its body diode has soft recovery (S = 0.85) and 26.8 nC Q_r, but the device lacks dedicated reverse-conduction timing specs, diode forward voltage optimization, or gate-drive timing recommendations required for SR topologies.

Does the mounting base require electrical isolation from the PCB ground plane?

Yes - the mounting base is internally connected to the drain terminal. When used in high-side configurations or where drain is at elevated potential, the copper pad must be isolated using dielectric thermal interface material or non-conductive heatsink mounting. Direct soldering to a grounded copper pour creates a short circuit unless drain is referenced to system ground.

BUK9Y1R9-40HX Specifications

Product attributes: Attribute value

Manufacturer:: Nexperia USA Inc.

Series:: -

Package/Case:: -

Packaging:: Tape & Reel (TR)

Product Status:: Active

FET Type:: -

Technology:: -

Drain to Source Voltage (Vdss):: -

Current - Continuous Drain (Id) @ 25°C:: 120A (Tc)

Drive Voltage (Max Rds On, Min Rds On):: -

Rds On (Max) @ Id, Vgs:: -

Vgs(th) (Max) @ Id:: -

Gate Charge (Qg) (Max) @ Vgs:: -

Vgs (Max):: +16V, -10V

Input Capacitance (Ciss) (Max) @ Vds:: -

FET Feature:: -

Power Dissipation (Max):: 217W (Tc)

Operating Temperature:: -

Grade:: Automotive

Qualification:: AEC-Q101

Mounting Type:: -

Supplier Device Package:: -

BUK9Y1R9-40HX FAQ

1.How can I place an order for BUK9Y1R9-40HX through Aetrix?

Please submit a Request for Quotation (RFQ) for BUK9Y1R9-40HX 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 BUK9Y1R9-40HX reliable?

The price and inventory of BUK9Y1R9-40HX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BUK9Y1R9-40HX is usually 5 days.

3.What payment methods are accepted for BUK9Y1R9-40HX?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BUK9Y1R9-40HX transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BUK9Y1R9-40HX?

BUK9Y1R9-40HX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BUK9Y1R9-40HX 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 BUK9Y1R9-40HX?

For technical support, including BUK9Y1R9-40HX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BUK9Y1R9-40HX requirements.

6.How does Aetrix verify that BUK9Y1R9-40HX is sourced from the original manufacturer or authorized distributors?

All BUK9Y1R9-40HX 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 BUK9Y1R9-40HX meets industry standards.

7.What is the process for return or replacement of BUK9Y1R9-40HX?

All BUK9Y1R9-40HX units undergo pre-shipment inspection (PSI). If there is an issue with BUK9Y1R9-40HX, 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 BUK9Y1R9-40HX part is unused and in its original packaging.

Return procedure for BUK9Y1R9-40HX:

1.Submit a request within 90 days.

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

Tech Hub

2026-09-03 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

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.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

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…

2026-09-01 74HC595 Pinout, Timing, Output Current, and Applications

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…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

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…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

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 …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

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…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

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…

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

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…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

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…

2026-08-14 Jumper Cables: How to Use, Connect and Choose Them Safely

Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…