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Nexperia USA Inc. BUK7M21-40EX
- Part No.:
- BUK7M21-40EX
- Manufacturer:
- Nexperia USA Inc.
- Category:
- FETs, MOSFETs
- Package:
- SOT-1210, 8-LFPAK33 (5-Lead)
- Datasheet:
-
BUK7M21-40EX.pdf
- Description:
- MOSFET N-CH 40V 33A LFPAK33
- Quantity:
- Payment:
- Shipping:
Inventory:207
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Product details
Overview
BUK7M21-40EX from Nexperia is a standard-level N-channel MOSFET in LFPAK33 (SOT1210) package, rated for 40 V VDS, 21 mΩ RDS(on) at 10 V VGS and 25 °C, and qualified to AEC-Q101 for automotive use. It delivers 33 A continuous drain current at Tmb = 25 °C, supports repetitive avalanche operation, and features true standard gate drive with VGS(th) > 1 V at 175 °C - deployed in 12 V automotive motor and solenoid control circuits.
For engineers reviewing the BUK7M21-40EX datasheet, BUK7M21-40EX pinout, BUK7M21-40EX application, or BUK7M21-40EX equivalent, key selection criteria include its 175 °C junction rating, 2.77 K/W Rth(j-mb), Q101 qualification, LFPAK33 thermal performance, and gate threshold stability under high-temperature automotive transients.
Technical Context
This MOSFET employs TrenchMOS technology in an LFPAK33 package with integrated mounting base connected to drain, enabling low-inductance, high-current switching and efficient heat transfer to PCB copper. Its standard-level gate (VGS(th) > 1 V at 175 °C) ensures reliable turn-on with conventional 5 V or 12 V logic drivers without level-shifting.
The device is specified for repetitive avalanche operation and exhibits 11.6 mJ non-repetitive EAS at 33 A, supporting robustness against inductive load switching transients. Thermal resistance from junction to mounting base is 2.77 K/W typical, allowing high power density in space-constrained automotive modules.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VDS | 40 V - Maximum drain-source blocking voltage compatible with 12 V automotive systems including load-dump and ISO 7637-2 pulse conditions. |
| RDS(on) | 17–21 mΩ @ VGS = 10 V, ID = 10 A, Tj = 25 °C - Enables low conduction loss in high-current switching nodes like transmission actuators. |
| ID (continuous) | 33 A @ Tmb = 25 °C - Supports high-power loads such as radiator fans or fuel pumps without external heatsinking. |
| Ptot | 44 W @ Tmb = 25 °C - Reflects high thermal efficiency of LFPAK33 package with direct die-to-mounting-base path. |
| Rth(j-mb) | 2.77 K/W typical - Enables precise thermal modeling and predictable derating up to 175 °C junction temperature. |
| VGS(th) | > 1 V @ Tj = 175 °C - Ensures guaranteed turn-on with standard microcontroller GPIO or automotive driver ICs across full temperature range. |
| QGD | 3.8 nC @ VDS = 32 V, ID = 10 A - Low gate-drain charge minimizes Miller-induced switching delay and improves hard-switching efficiency. |
Pinout & Package
LFPAK33 (SOT1210) is a surface-mount, single-ended power package with exposed mounting base for enhanced thermal and electrical performance. The mounting base is internally connected to the drain terminal, enabling low-inductance, high-current routing directly to PCB ground plane or thermal pad.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 2, 3 | Source (S) | Three parallel source terminals reduce bond-wire inductance and improve current sharing in high-frequency PWM applications. |
| 4 | Gate (G) | Single gate input with low input capacitance (Ciss = 446–593 pF) for fast, low-loss switching with standard gate drivers. |
| Mounting Base (mb) | Drain (D) | Exposed copper pad electrically and thermally tied to drain - serves as primary current path and thermal interface to PCB. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive-grade reliability including temperature cycling, HTRB, and UHAST - suitable for safety-critical body electronics. |
| Repetitive avalanche rated | Guaranteed operation under inductive switching stress without degradation - eliminates need for external snubbers in solenoid drivers. |
| 175 °C maximum junction temperature | Enables placement near hot engine compartments or inside sealed ECUs without thermal derating penalties. |
| True standard-level gate | VGS(th) > 1 V at 175 °C ensures consistent turn-on with 5 V MCU outputs, avoiding gate driver complexity in cost-sensitive modules. |
| Low Rth(j-mb) | 2.77 K/W typical enables >90% of rated power dissipation to be transferred directly to PCB - reduces need for external heatsinks. |
Applications
| Engine Cooling Fan Control | Automatic Transmission Solenoid Driver |
|---|---|
|
Use Scenario: PWM-controlled 12 V DC brushless fan in engine bay, operating continuously at ambient up to 125 °C. IC Role / Device Role / Timing Role: High-side or low-side power switch managing up to 30 A peak current during ramp-up and stall conditions. Use Value: 21 mΩ RDS(on) and 175 °C rating minimize conduction loss and ensure stable operation without thermal shutdown. |
Use Scenario: Driving 12 V transmission shift solenoids requiring precise 5–10 ms on/off timing and high surge current tolerance. IC Role / Device Role / Timing Role: Low-side switching element handling repetitive inductive kickback and pulsed 25 A peak currents. Use Value: Repetitive avalanche capability and 11.6 mJ EAS absorb energy from solenoid collapse without clamping diodes or TVS. |
| Electric Power Steering (EPS) Motor Phase Switch | Body Control Module (BCM) Lamp Load Switch |
|
Use Scenario: Half-bridge phase leg in 12 V EPS motor driver, switching at 20 kHz with 30 A RMS current. IC Role / Device Role / Timing Role: Fast-switching N-channel MOSFET with low QGD (3.8 nC) minimizing dead-time losses and shoot-through risk. Use Value: Low gate-drain charge and 3.8 ns rise time enable clean, efficient commutation while maintaining EMC compliance. |
Use Scenario: Centralized lamp load switching in BCM for headlights, fog lamps, and interior lighting with diagnostic feedback. IC Role / Device Role / Timing Role: Protected high-current switch with integrated current sensing compatibility and short-circuit robustness. Use Value: Standard-level gate allows direct MCU control; 33 A rating supports multiple parallel lamps without paralleling devices. |
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, 1.7 mΩ RDS(on), 220 A rated, but requires gate voltage ≥ 4.5 V for full enhancement; not AEC-Q101 qualified. | Targeted at industrial motor drives, not automotive-qualified systems; lacks repetitive avalanche rating. | Select only for non-automotive, high-current applications where gate drive voltage ≥ 4.5 V is guaranteed and qualification is not required. |
| ON Semiconductor NTMFS4C09NT1G | 40 V, 2.1 mΩ RDS(on), 120 A rated, AEC-Q101 qualified, but uses SO-8FL package with higher Rth(j-mb) (3.5 K/W). | Better suited for lower-power, space-constrained modules where footprint is prioritized over thermal performance. | Prefer when board area is limited and thermal margin allows higher Rth; avoid where mounting base thermal coupling is critical. |
Compared with STL220N4F7AG and NTMFS4C09NT1G, BUK7M21-40EX uniquely balances AEC-Q101 compliance, 175 °C operation, low Rth(j-mb), and standard-level gate drive - making it optimal for thermally demanding, safety-critical automotive switches where gate simplicity and thermal predictability are design priorities.
Availability
BUK7M21-40EX is available at Aetrix Electronics and suitable for automotive body electronics, transmission control units, and electric power steering systems requiring stable component supply, long-term lifecycle support, and traceable sourcing.
Supply support for BUK7M21-40EX 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 high-volume, high-reliability discrete and logic components, with leadership in automotive-qualified MOSFETs and ESD protection devices.
BUK7M21-40EX belongs to Nexperia's Automotive Logic and Power portfolio, engineered specifically for robust, thermally efficient switching in 12 V automotive subsystems - emphasizing AEC-Q101 compliance, avalanche ruggedness, and LFPAK thermal performance.
FAQ
Is BUK7M21-40EX pin-compatible with other LFPAK33 MOSFETs?
Yes - BUK7M21-40EX uses the standardized SOT1210 footprint with identical pin assignment (1–3: Source, 4: Gate, mounting base: Drain). It shares mechanical and solder-reflow compatibility with all Nexperia LFPAK33 N-channel MOSFETs, enabling drop-in replacement within the same voltage and RDS(on) class.
What is the maximum safe operating temperature for the mounting base?
The mounting base temperature (Tmb) must not exceed 175 °C to maintain rated performance and reliability. Derating curves in Figure 2 show continuous drain current drops linearly from 33 A at 25 °C Tmb to 23.1 A at 100 °C Tmb, confirming safe operation up to the absolute max junction temperature.
Does BUK7M21-40EX require a gate resistor for automotive PWM applications?
A gate resistor (typically 5–22 Ω) is recommended to dampen ringing and control dV/dt during switching, especially in high-di/dt automotive loads. The device's low QGD (3.8 nC) and Ciss (446–593 pF) allow fast switching, but uncontrolled edge rates may cause EMI or shoot-through in half-bridge configurations.
Can BUK7M21-40EX replace a TO-220 MOSFET in an existing automotive design?
Yes - with PCB layout adaptation. The LFPAK33 package offers superior thermal resistance (2.77 K/W vs. ~3.5–5.0 K/W for TO-220) and smaller footprint. Replacement requires redesigning the thermal pad and gate/source routing, but delivers improved power density, lower inductance, and better vibration resistance in automotive environments.
BUK7M21-40EX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- TrenchMOS™
- Package/Case:
- SOT-1210, 8-LFPAK33 (5-Lead)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- FET Type:
- N-Channel
- Technology:
- MOSFET (Metal Oxide)
- Drain to Source Voltage (Vdss):
- 40 V
- Current - Continuous Drain (Id) @ 25°C:
- 33A (Tc)
- Drive Voltage (Max Rds On, Min Rds On):
- 10V
- Rds On (Max) @ Id, Vgs:
- 21mOhm @ 10A, 10V
- Vgs(th) (Max) @ Id:
- 4V @ 1mA
- Gate Charge (Qg) (Max) @ Vgs:
- 10.7 nC @ 10 V
- Vgs (Max):
- ±20V
- Input Capacitance (Ciss) (Max) @ Vds:
- 593 pF @ 25 V
- FET Feature:
- -
- Power Dissipation (Max):
- 44W (Tc)
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- LFPAK33
BUK7M21-40EX FAQ
1.How can I place an order for BUK7M21-40EX through Aetrix?
Please submit a Request for Quotation (RFQ) for BUK7M21-40EX 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 BUK7M21-40EX reliable?
The price and inventory of BUK7M21-40EX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BUK7M21-40EX is usually 5 days.
3.What payment methods are accepted for BUK7M21-40EX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BUK7M21-40EX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BUK7M21-40EX?
BUK7M21-40EX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BUK7M21-40EX 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 BUK7M21-40EX?
For technical support, including BUK7M21-40EX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BUK7M21-40EX requirements.
6.How does Aetrix verify that BUK7M21-40EX is sourced from the original manufacturer or authorized distributors?
All BUK7M21-40EX 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 BUK7M21-40EX meets industry standards.
7.What is the process for return or replacement of BUK7M21-40EX?
All BUK7M21-40EX units undergo pre-shipment inspection (PSI). If there is an issue with BUK7M21-40EX, 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 BUK7M21-40EX part is unused and in its original packaging.
Return procedure for BUK7M21-40EX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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