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Nexperia USA Inc. BUK9Y21-40E,115
- Part No.:
- BUK9Y21-40E,115
- Manufacturer:
- Nexperia USA Inc.
- Category:
- FETs, MOSFETs
- Package:
- SC-100, SOT-669
- Datasheet:
-
BUK9Y21-40E,115.pdf
- Description:
- MOSFET N-CH 40V 33A LFPAK56
- Quantity:
- Payment:
- Shipping:
Inventory:6,924
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Product details
Overview
BUK9Y21-40E from Nexperia is an AEC-Q101 qualified N-channel logic-level MOSFET in LFPAK56 (SOT669) package, rated for 40 V VDS, 21 mΩ RDS(on) at VGS = 5 V and Tj = 25 °C, with 175 °C junction temperature rating and repetitive avalanche capability - deployed in automotive transmission control and high-reliability 12 V power switching.
For engineers reviewing the BUK9Y21-40E datasheet, BUK9Y21-40E pinout, BUK9Y21-40E application, or BUK9Y21-40E equivalent, key selection criteria include its true logic-level gate (VGS(th) > 0.5 V at 175 °C), low thermal resistance (Rth(j-mb) = 3.33 K/W), and mounting-base–referenced power dissipation up to 45 W at Tmb = 25 °C.
Technical Context
This MOSFET uses TrenchMOS technology to achieve stable RDS(on) across temperature and robust avalanche ruggedness (EAS = 12 mJ, unclamped). Its gate threshold voltage remains functional up to 175 °C, enabling direct 5 V microcontroller drive without level-shifting in thermally demanding automotive environments.
The LFPAK56 package integrates a drain-connected mounting base (mb) for low-inductance, high-current PCB thermal conduction. Pin configuration features three parallel source terminals (Pins 1–3), single gate (Pin 4), and drain tied to the exposed metal base - optimizing current sharing, thermal transfer, and switching efficiency in high-dI/dt applications.
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 transients. |
| RDS(on) | 21 mΩ max @ VGS = 5 V, ID = 10 A, Tj = 25 °C - Enables <1 W conduction loss at 7 A continuous current, reducing heatsink requirements. |
| ID | 33 A @ Tmb = 25 °C - Continuous drain current rating referenced to mounting base temperature, not ambient, supporting accurate thermal design. |
| Rth(j-mb) | 3.33 K/W - Junction-to-mounting-base thermal resistance enables efficient heat extraction via PCB copper pour or heatsink interface. |
| QGD | 2.7 nC - Low gate-drain charge minimizes Miller-induced switching delay and improves turn-off robustness in inductive loads. |
| VGS(th) | > 0.5 V @ Tj = 175 °C - Guaranteed turn-on with standard 5 V logic, eliminating need for gate boosters in high-temp engine bay locations. |
| EAS | 12 mJ - Single-pulse unclamped avalanche energy rating supports reliable operation during inductive flyback events without external snubbers. |
Pinout & Package
LFPAK56 (SOT669) is a surface-mount plastic package with an exposed drain-connected mounting base for enhanced thermal and electrical performance. It provides mechanical robustness and solder joint reliability under automotive thermal cycling.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1, 2, 3 - S | Source | Three parallel source terminals reduce package inductance and improve current sharing; connected internally to common source node. |
| 4 - G | Gate | Single gate input with low input capacitance (Ciss = 618–824 pF); optimized for 5 V logic drive and fast switching. |
| mb - D | Drain / Mounting Base | Exposed metal pad electrically connected to drain; serves as primary thermal path and high-current return path to PCB ground plane. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive-grade reliability including temperature cycling, HTRB, and ESD per JESD47 - suitable for safety-critical power nodes. |
| Repetitive avalanche rated | Rated for repeated unclamped inductive switching events without degradation - eliminates need for external clamping diodes in solenoid drivers. |
| 175 °C junction rating | Enables operation in under-hood environments (e.g., transmission control modules) without derating or forced cooling. |
| True logic-level gate | VGS(th) > 0.5 V at 175 °C ensures guaranteed turn-on with standard 5 V MCU GPIOs - no gate driver IC required. |
| Low Rth(j-mb) | 3.33 K/W thermal resistance allows >30 W power dissipation with only 100 °C ΔT between junction and mounting base - simplifies thermal layout. |
Applications
| Transmission Control Valve Driver | Engine Cooling Fan Controller |
|---|---|
Use Scenario: PWM-driven hydraulic solenoid valves regulating gear shift timing and pressure in automatic transmissions. IC Role / Device Role / Timing Role: High-side or low-side switching element delivering up to 33 A peak current with precise duty-cycle control. Use Value: Repetitive avalanche rating absorbs solenoid back-EMF without snubbers; 175 °C rating ensures stability during prolonged high-load shifts. |
Use Scenario: Variable-speed DC brushless fan motor control in engine bay, operating continuously at elevated ambient temperatures. IC Role / Device Role / Timing Role: Low-side power switch modulating motor current via 20–25 kHz PWM to minimize acoustic noise. Use Value: 21 mΩ RDS(on) limits conduction loss to <0.5 W at 5 A, reducing thermal stress on PCB; LFPAK56 base enhances heatsinking. |
| LED Headlamp Matrix Switch | 12 V Battery Disconnect Switch |
Use Scenario: Individual pixel-level switching of high-brightness LED strings in adaptive driving beam (ADB) headlamps. IC Role / Device Role / Timing Role: Fast-switching N-channel MOSFET enabling microsecond-level on/off transitions for dynamic light patterning. Use Value: Low QGD (2.7 nC) and fast tr/tf (9.7/8.2 ns) support clean edge control and minimal shoot-through risk in multi-FET arrays. |
Use Scenario: Solid-state replacement for mechanical relays in battery management systems, isolating starter/load circuits during sleep mode. IC Role / Device Role / Timing Role: High-reliability power switch handling 30+ A inrush and steady-state currents with zero contact wear. Use Value: AEC-Q101 qualification and 40 V VDS withstand capability ensure long-term integrity against load dump spikes (up to ±40 V). |
Equivalent & Alternatives
The following parts are listed as comparable options for similar N-channel automotive MOSFET applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STL220N4F7AG | 40 V, 1.7 mΩ RDS(on) @ 10 V, but requires 10 V gate drive; not logic-level at 5 V. | Better conduction efficiency at higher gate voltage; unsuitable for direct 5 V MCU drive. | Select when gate driver circuitry is available and ultra-low RDS(on) outweighs gate voltage constraints. |
| ON Semiconductor NTMFS4C09NT1G | 40 V, 2.9 mΩ @ 10 V; logic-level (VGS(th) = 1.2–2.2 V), but only rated to 150 °C Tj. | Lacks AEC-Q101 qualification and high-temp gate stability; limited to cabin-mounted modules. | Acceptable for non-engine-bay 12 V systems where 175 °C operation is not required. |
Compared with STL220N4F7AG and NTMFS4C09NT1G, BUK9Y21-40E uniquely combines AEC-Q101 qualification, true 5 V logic-level operation at 175 °C, and proven avalanche ruggedness - making it the only drop-in solution for thermally aggressive, safety-critical automotive power switching without gate boosting or derating.
Availability
BUK9Y21-40E is available at Aetrix Electronics and suitable for automotive transmission control, engine cooling fan regulation, and adaptive LED headlamp systems requiring stable component supply across extended temperature ranges and long product lifecycles.
Supply support for BUK9Y21-40E 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 semiconductor expert focused on high-volume, high-reliability discrete and logic devices, with leadership in automotive-qualified MOSFETs, ESD protection, and logic solutions.
BUK9Y21-40E belongs to Nexperia's LFPAK automotive MOSFET family, engineered specifically for robust, high-efficiency power switching in 12 V vehicle subsystems where thermal resilience, avalanche tolerance, and AEC-Q101 compliance are mandatory.
FAQ
Is BUK9Y21-40E suitable for high-side switching configurations?
No - BUK9Y21-40E is an N-channel MOSFET with source terminals tied to internal reference; high-side switching requires either a P-channel device or an N-channel with floating gate driver. Its pinout and thermal design optimize low-side use with drain-connected mounting base.
What is the maximum continuous drain current at 100 °C mounting base temperature?
Per Figure 1 in the datasheet, the continuous drain current is 23 A at Tmb = 100 °C and VGS = 5 V. This reflects thermal derating due to reduced heat transfer efficiency at elevated mounting base temperatures.
Does BUK9Y21-40E require a gate resistor for safe operation?
A gate resistor (typically 5–10 Ω) is recommended to dampen ringing and control dV/dt during switching, especially in inductive loads. The datasheet specifies test conditions with RG(ext) = 5 Ω for switching time measurements, confirming its necessity for EMI and reliability control.
Can BUK9Y21-40E replace older BUK9Y21-40B in existing designs?
Yes - BUK9Y21-40E is a direct replacement for BUK9Y21-40B, sharing identical pinout, package (LFPAK56), and electrical specifications. The 'E' suffix denotes updated wafer process and enhanced avalanche ruggedness, with full backward compatibility in layout and drive circuitry.
BUK9Y21-40E,115 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- SC-100, SOT-669
- 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):
- 5V
- Rds On (Max) @ Id, Vgs:
- 17mOhm @ 10A, 10V
- Vgs(th) (Max) @ Id:
- 2.1V @ 1mA
- Gate Charge (Qg) (Max) @ Vgs:
- 7 nC @ 5 V
- Vgs (Max):
- ±10V
- Input Capacitance (Ciss) (Max) @ Vds:
- 824 pF @ 25 V
- FET Feature:
- -
- Power Dissipation (Max):
- 45W (Tc)
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- LFPAK56, Power-SO8
BUK9Y21-40E,115 FAQ
1.How can I place an order for BUK9Y21-40E,115 through Aetrix?
Please submit a Request for Quotation (RFQ) for BUK9Y21-40E,115 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 BUK9Y21-40E,115 reliable?
The price and inventory of BUK9Y21-40E,115 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BUK9Y21-40E,115 is usually 5 days.
3.What payment methods are accepted for BUK9Y21-40E,115?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BUK9Y21-40E,115 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BUK9Y21-40E,115?
BUK9Y21-40E,115 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BUK9Y21-40E,115 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 BUK9Y21-40E,115?
For technical support, including BUK9Y21-40E,115 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BUK9Y21-40E,115 requirements.
6.How does Aetrix verify that BUK9Y21-40E,115 is sourced from the original manufacturer or authorized distributors?
All BUK9Y21-40E,115 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 BUK9Y21-40E,115 meets industry standards.
7.What is the process for return or replacement of BUK9Y21-40E,115?
All BUK9Y21-40E,115 units undergo pre-shipment inspection (PSI). If there is an issue with BUK9Y21-40E,115, 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 BUK9Y21-40E,115 part is unused and in its original packaging.
Return procedure for BUK9Y21-40E,115:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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