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Nexperia USA Inc. MJD148-QJ
- Part No.:
- MJD148-QJ
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- TO-252-3, DPAK (2 Leads + Tab), SC-63
- Datasheet:
-
MJD148-QJ.pdf
- Description:
- TRANS NPN 45V 4A DPAK
- Quantity:
- Payment:
- Shipping:
Inventory:2,097
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Product details
Overview
MJD148-QJ from Nexperia is a 45 V, 4 A NPN high-power bipolar transistor in DPAK (SOT428C) package, designed for automotive-grade load switching and linear regulation. It delivers 30–375 DC current gain at 3 A, 0.5 V collector-emitter saturation voltage at 2 A/0.2 A drive, and supports 7 A peak pulsed current. Used in motor drive circuits requiring robust thermal performance and AEC-Q101 qualification.
For engineers reviewing the MJD148-QJ datasheet, MJD148-QJ pinout, MJD148-QJ application, or MJD148-QJ equivalent, this page provides verified electrical parameters, thermal resistance values (Rth(j-mb) = 9 K/W), mounting-base-connected collector topology, and automotive-qualified switching behavior under linear and saturated operation.
Technical Context
This NPN power transistor operates in both linear and saturated modes, with base-emitter voltage ≤1.1 V at 2 A collector current and transition frequency of 3 MHz at 250 mA. Its low VCE(sat) enables efficient conduction in constant-current backlight drivers and relay-replacement circuits.
The device features an integrated mounting base electrically connected to the collector, enabling direct thermal coupling to heatsinks or PCB copper pads. Thermal resistance from junction to mounting base is 9 K/W in free air, supporting 15 W total power dissipation when properly mounted.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 45 V - Maximum safe collector-emitter voltage with open base; defines breakdown margin in 12 V/24 V automotive systems. |
| IC | 4 A continuous - Sustained collector current rating; supports motor coils and solenoid loads without forced cooling. |
| hFE | 30–375 at IC = 0.5–3 A - Wide DC gain range enables stable biasing across temperature and current conditions. |
| VCE(sat) | ≤0.5 V at IC = 2 A, IB = 0.2 A - Low saturation voltage minimizes conduction loss in high-current switching applications. |
| Rth(j-mb) | 9 K/W - Junction-to-mounting-base thermal resistance; allows direct thermal path to heatsink or large copper area. |
| Ptot | 15 W at Tmb ≤ 25 °C - Total power dissipation limit when mounting base is actively cooled. |
| AEC-Q101 | Qualified - Meets stress-test requirements for discrete semiconductors in automotive environments. |
Pinout & Package
DPAK (SOT428C) surface-mount plastic package with three leads and integral metal mounting base electrically tied to the collector terminal. Package dimensions: 10.4 × 6.73 × 2.38 mm (L × W × H); mounting pad area 1 cm² on FR4 PCB.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Control input; requires ~0.2 A base current to saturate at 2 A collector load. |
| 2 | Collector (C) | Main current path input; internally bonded to mounting base for thermal and electrical connection. |
| 3 | Emiter (E) | Current return path; referenced to system ground in common-emitter configurations. |
| Mounting Base (mb) | Collector (C) | Electrically and thermally connected to pin 2; must be soldered to large copper pour or heatsink. |
Key Features
| Feature | Design Value |
|---|---|
| High thermal power dissipation | 15 W junction-to-mounting-base rating enables operation without external heatsink in moderate-duty cycles. |
| Low VCE(sat) | 0.5 V max at 2 A ensures <1 W conduction loss, critical for efficiency in linear-mode regulators and backlight drivers. |
| AEC-Q101 qualification | Validated for automotive underhood and cabin applications including motor control and body electronics. |
| Fast switching speed | 3 MHz fT supports PWM frequencies up to several hundred kHz in switching regulators and LED dimming. |
| Electrically similar to MJD148 series | Drop-in compatibility with legacy MJD148 designs simplifies upgrade paths while adding automotive qualification. |
Applications
| Motor Drive | Linear Voltage Regulator |
|---|---|
|
Use Scenario: Driving brushed DC motors in automotive HVAC actuators and seat positioners. IC Role / Device Role / Timing Role: High-current NPN switch controlling motor direction and speed via PWM. Use Value: 4 A continuous current and 7 A pulse rating support stall-tolerant actuation; low VCE(sat) reduces heat buildup during PWM on-time. |
Use Scenario: Adjustable linear regulator supplying stable 5 V to microcontroller peripherals in infotainment modules. IC Role / Device Role / Timing Role: Pass transistor in emitter-follower configuration with feedback control loop. Use Value: 30–375 hFE ensures stable loop gain across temperature; mounting-base thermal path maintains regulation accuracy under load transients. |
| Backlight Constant Current Driver | Relay Replacement |
|
Use Scenario: Driving LED strings in instrument cluster backlighting with precise current control. IC Role / Device Role / Timing Role: Linear-mode current source with sense-resistor feedback and base bias adjustment. Use Value: Low VBE variation (≤1.1 V) and tight hFE tolerance enable ±3% current regulation across production units. |
Use Scenario: Solid-state replacement for electromechanical relays in door lock and window lift control units. IC Role / Device Role / Timing Role: High-side or low-side load switch interfacing with 3.3 V/5 V MCU GPIOs. Use Value: AEC-Q101 qualification ensures reliability over 100,000 cycles; mounting base improves long-term contact integrity vs. relay contacts. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ON Semiconductor MJD127G | 40 V VCEO, 3 A IC, no AEC-Q101 qualification, TO-252 package with isolated mounting base. | Limited to non-automotive industrial use; lower voltage/current headroom reduces design margin in 24 V systems. | Select when cost sensitivity outweighs automotive compliance and thermal performance requirements. |
| STMicroelectronics BD139 | 80 V VCEO, 1.5 A IC, TO-126 through-hole package, no automotive qualification. | Suitable only for low-power linear regulators and signal amplification; insufficient current for motor or relay replacement. | Choose for prototyping or legacy through-hole designs where footprint and qualification are secondary. |
Compared with MJD148-QJ, MJD127G offers lower cost but sacrifices AEC-Q101 compliance and thermal capability, while BD139 trades voltage headroom for manufacturability-neither matches the 45 V/4 A/AEC-Q101 triad essential for modern automotive power switching.
Availability
MJD148-QJ is available at Aetrix Electronics and suitable for automotive motor control, linear voltage regulation, and solid-state relay replacement requiring stable component supply and AEC-Q101 assurance.
Supply support for MJD148-QJ 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 logic, analog, and discrete components, headquartered in Nijmegen, Netherlands.
The MJD148-QJ belongs to Nexperia's AEC-Q101-qualified power transistor family, engineered specifically for automotive power management where thermal robustness, consistent gain, and long-term reliability are mandatory.
FAQ
Is MJD148-QJ pin-compatible with standard MJD148 variants?
Yes-MJD148-QJ uses the same DPAK (SOT428C) pinout as non-automotive MJD148 devices: Pin 1 = Base, Pin 2 = Collector (mounted to base), Pin 3 = Emitter. The marking "MJD148A" on the package confirms functional equivalence with enhanced qualification.
What is the maximum allowable PCB copper area for thermal performance?
For optimal thermal performance, Nexperia specifies a 1 cm² tin-plated copper mounting pad on FR4 PCB with single-sided 70 µm copper. Increasing pad size beyond this yields diminishing returns unless combined with internal copper planes or external heatsinking.
Can MJD148-QJ operate in avalanche mode?
No-MJD148-QJ is not rated for repetitive avalanche operation. Its absolute maximum VCEO of 45 V applies only under open-base conditions; operation near breakdown without clamping risks permanent degradation due to localized heating.
Does the mounting base require electrical isolation from chassis ground?
Yes-the mounting base is electrically connected to the collector (Pin 2). If the collector circuit is not referenced to chassis ground, the mounting base must be insulated using thermal pads or isolated heatsinks to prevent short circuits.
MJD148-QJ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Nexperia USA Inc.
- Series:
- -
- Package/Case:
- TO-252-3, DPAK (2 Leads + Tab), SC-63
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 4 A
- Voltage - Collector Emitter Breakdown (Max):
- 45 V
- Vce Saturation (Max) @ Ib, Ic:
- 500mV @ 200mA, 2A
- Current - Collector Cutoff (Max):
- 1µA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 85 @ 500mA, 1V
- Power - Max:
- 1.6 W
- Frequency - Transition:
- 3MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DPAK
MJD148-QJ FAQ
1.How can I place an order for MJD148-QJ through Aetrix?
Please submit a Request for Quotation (RFQ) for MJD148-QJ 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 MJD148-QJ reliable?
The price and inventory of MJD148-QJ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MJD148-QJ is usually 5 days.
3.What payment methods are accepted for MJD148-QJ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MJD148-QJ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MJD148-QJ?
MJD148-QJ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MJD148-QJ 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 MJD148-QJ?
For technical support, including MJD148-QJ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MJD148-QJ requirements.
6.How does Aetrix verify that MJD148-QJ is sourced from the original manufacturer or authorized distributors?
All MJD148-QJ 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 MJD148-QJ meets industry standards.
7.What is the process for return or replacement of MJD148-QJ?
All MJD148-QJ units undergo pre-shipment inspection (PSI). If there is an issue with MJD148-QJ, 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 MJD148-QJ part is unused and in its original packaging.
Return procedure for MJD148-QJ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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