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Nexperia USA Inc. MJD31CAJ
- Part No.:
- MJD31CAJ
- Manufacturer:
- Nexperia USA Inc.
- Category:
- Single Bipolar Transistors
- Package:
- TO-252-3, DPAK (2 Leads + Tab), SC-63
- Datasheet:
-
MJD31CAJ.pdf
- Description:
- TRANS NPN 100V 3A DPAK
- Quantity:
- Payment:
- Shipping:
Inventory:4,322
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Product details
Overview
MJD31CAJ from Nexperia is an AEC-Q101-qualified NPN high-power bipolar transistor in DPAK (SOT428C) package, rated for 100 V VCEO, 3 A continuous IC, and 15 W junction-to-mounting-base power dissipation. It serves as a robust load switch or linear regulator pass device in automotive power management systems, delivering low 1.2 V VCE(sat) at 3 A/375 mA drive and fast switching for motor drive and relay replacement.
For engineers reviewing the MJD31CAJ datasheet, MJD31CAJ pinout, MJD31CAJ application, or MJD31CAJ equivalent, this page provides verified thermal resistance (Rth(j-mb) = 9 K/W), DC current gain (hFE = 10–50 at 3 A), saturation voltage behavior, AEC-Q101 qualification status, and mounting-base thermal interface requirements for PCB layout validation.
Technical Context
This discrete NPN transistor operates in active, saturation, and cutoff regions with defined safe operating area (SOA) up to 100 V and 3 A under Tamb ≤ 25 °C. Its base-emitter forward voltage is 1.8 V max at 3 A, and transition frequency fT reaches 3 MHz at 10 V/500 mA, supporting medium-speed switching in constant-current backlight drivers and linear-mode regulators.
The device features electrically similar characteristics to legacy MJD31 series transistors but adds AEC-Q101 qualification and improved thermal performance via direct collector-to-mounting-base connection. Thermal derating follows a linear curve from 15 W at Tmb ≤ 25 °C to zero at 150 °C junction temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 100 V - Maximum collector-emitter voltage before breakdown with base open; defines maximum blocking capability in load-switch applications. |
| IC | 3 A - Continuous collector current rating at Tamb ≤ 25 °C; sets steady-state current-handling limit for motor drive or relay replacement. |
| VCE(sat) | 1.2 V max at IC = 3 A, IB = 375 mA - Low saturation voltage minimizes conduction loss and heat generation in linear-mode operation. |
| hFE | 10–50 at VCE = 4 V, IC = 3 A - Confirmed DC current gain range determines required base drive current for full saturation. |
| Rth(j-mb) | 9 K/W - Junction-to-mounting-base thermal resistance enables efficient heat transfer to heatsink or copper pour when mounted correctly. |
| AEC-Q101 | Qualified - Validated for automotive-grade reliability including temperature cycling, HTRB, and ESD per AEC standard; suitable for under-hood use. |
| Ptot (j-mb) | 15 W - Total power dissipation limit referenced to mounting base temperature ≤ 25 °C; defines thermal design headroom before derating. |
Pinout & Package
DPAK (SOT428C) surface-mount plastic package with three leads and integral metal mounting base connected directly to the collector terminal. The package measures 10.40 × 6.73 mm with 2.38 mm lead pitch and requires tin-plated 1 cm² copper pad on FR4 PCB for optimal thermal performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base (B) | Control input node requiring ~375 mA drive current to saturate at 3 A collector current; must be driven with appropriate current-limiting resistor or driver stage. |
| 2 | Collector (C) | Main power output node electrically tied to mounting base; connects to load or supply rail and must be thermally coupled to PCB copper or external heatsink. |
| 3 | Emiter (E) | Power return path; forms common emitter configuration with base control and collector load; referenced to system ground or negative rail. |
| Mounting Base (mb) | Collector (C) | Exposed metal pad soldered to PCB copper; carries full collector current and conducts heat directly from die; must not be electrically isolated from collector net. |
Key Features
| Feature | Design Value |
|---|---|
| High thermal power dissipation | 15 W junction-to-mounting-base rating enables compact thermal design without external heatsink in many 3 A applications. |
| Low VCE(sat) | 1.2 V max at full 3 A load reduces conduction losses to <3.6 W, lowering self-heating and improving efficiency in linear regulators. |
| AEC-Q101 qualification | Validated for automotive environments including temperature cycling, high-temperature reverse bias, and ESD robustness per AEC standard. |
| Fast switching speeds | fT = 3 MHz supports sub-microsecond turn-on/turn-off in PWM-driven motor or backlight circuits without excessive switching loss. |
| Electrically similar to MJD31 series | Drop-in compatibility with legacy MJD31 designs simplifies upgrade paths while adding automotive qualification and thermal improvements. |
Applications
| Automotive Power Management | Linear Mode Voltage Regulator |
|---|---|
|
Use Scenario: Controlling 12 V battery-fed loads such as HVAC actuators, window lift motors, or lighting modules in passenger vehicles. IC Role / Device Role / Timing Role: High-current NPN switch replacing mechanical relays; operated in saturation for low-loss on-state and cutoff for full isolation. Use Value: Eliminates relay coil power draw and contact wear while maintaining AEC-Q101 compliance and 100 V transient tolerance for load dump protection. |
Use Scenario: Adjustable linear regulator delivering stable 5–24 V output for infotainment subsystems or sensor bias rails. IC Role / Device Role / Timing Role: Pass element controlled by error amplifier feedback; operates in active region to regulate output voltage dynamically. Use Value: Leverages low VCE(sat) and high hFE to minimize dropout voltage and improve regulation accuracy under 3 A load. |
| Constant Current Backlight Drive | Motor Drive (DC Brushed) |
|
Use Scenario: Driving LED strings in instrument cluster or center console displays requiring precise current regulation across temperature. IC Role / Device Role / Timing Role: Constant-current sink configured with emitter resistor and base bias; maintains fixed current independent of LED forward voltage variation. Use Value: Stable hFE over −55 °C to 150 °C ensures consistent current setting without digital compensation or trimming. |
Use Scenario: Bidirectional H-bridge half-bridge leg for 12 V DC brushed motors in seat adjusters or sunroof mechanisms. IC Role / Device Role / Timing Role: High-side or low-side switching element; commutated at PWM frequencies up to 20 kHz using base drive circuitry. Use Value: 3 MHz fT and 1.2 V VCE(sat) reduce switching and conduction losses, enabling efficient 3 A motor control without forced air cooling. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN high-power switching applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STMicroelectronics STD36NF03L | N-channel MOSFET (30 V, 36 A, RDS(on) = 12 mΩ); gate-driven, no base current required. | Superior efficiency above 1 A due to lower on-resistance; unsuitable for linear-mode operation or >30 V applications. | Select for high-efficiency switching above 100 kHz; avoid where linear regulation or 100 V blocking is needed. |
| ON Semiconductor MJD31C | Same die and specs but non-AEC-Q101 qualified; identical pinout, VCEO, IC, and thermal performance. | Lacks automotive qualification testing; acceptable for industrial or consumer applications with less stringent reliability requirements. | Select for cost-sensitive non-automotive designs where AEC-Q101 is not mandated. |
Compared with STD36NF03L and MJD31C, MJD31CAJ uniquely combines 100 V blocking, AEC-Q101 qualification, and linear-mode capability-making it the only choice for automotive linear regulators or 12/24 V relay replacements requiring extended voltage margin and automotive reliability.
Availability
MJD31CAJ is available at Aetrix Electronics and suitable for automotive power management, linear voltage regulation, constant-current backlighting, and brushed DC motor drive applications requiring stable component supply and traceable sourcing.
Supply support for MJD31CAJ 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 components and advanced packaging technologies.
MJD31CAJ belongs to Nexperia's high-power bipolar transistor product line, engineered specifically for automotive and industrial power switching applications demanding AEC-Q101 reliability, thermal robustness, and proven field performance.
FAQ
What is the maximum allowable mounting base temperature for continuous operation?
The mounting base temperature must remain ≤25 °C to sustain the full 15 W power dissipation rating. Above 25 °C, power must be linearly derated per Figure 1 in the datasheet, reaching zero at 150 °C. For reliable long-term operation, maintain Tmb ≤ 85 °C using adequate PCB copper area or heatsinking.
Can MJD31CAJ be used in parallel configurations for higher current handling?
Yes, but only with emitter resistors (typically 0.1 Ω) to ensure current sharing. The device's positive temperature coefficient of VCE(sat) supports inherent thermal stability, but mismatched hFE between units requires individual base drive tuning or current-sensing feedback to prevent imbalance.
Is the mounting base electrically isolated from the collector pin?
No-the mounting base is internally connected to Pin 2 (collector) and must be treated as part of the collector net. Any PCB copper pour or heatsink attached to the mounting base must be electrically isolated from other nets unless intentionally tied to the collector potential.
What is the recommended reflow profile for SOT428C package assembly?
Use the JEDEC J-STD-020-compliant reflow profile specified in Figure 11 of the datasheet: peak temperature 260 °C for ≤30 seconds, with ramp-up rate ≤3 °C/s and ramp-down rate ≤6 °C/s. Ensure solder paste volume and stencil aperture match the 6.15 × 5.8 mm footprint with 1.8 mm pad spacing.
MJD31CAJ 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):
- 3 A
- Voltage - Collector Emitter Breakdown (Max):
- 100 V
- Vce Saturation (Max) @ Ib, Ic:
- 1.2V @ 375mA, 3A
- Current - Collector Cutoff (Max):
- 1µA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 25 @ 1A, 4V
- Power - Max:
- 1.6 W
- Frequency - Transition:
- 3MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DPAK
MJD31CAJ FAQ
1.How can I place an order for MJD31CAJ through Aetrix?
Please submit a Request for Quotation (RFQ) for MJD31CAJ 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 MJD31CAJ reliable?
The price and inventory of MJD31CAJ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MJD31CAJ is usually 5 days.
3.What payment methods are accepted for MJD31CAJ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MJD31CAJ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MJD31CAJ?
MJD31CAJ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MJD31CAJ 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 MJD31CAJ?
For technical support, including MJD31CAJ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MJD31CAJ requirements.
6.How does Aetrix verify that MJD31CAJ is sourced from the original manufacturer or authorized distributors?
All MJD31CAJ 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 MJD31CAJ meets industry standards.
7.What is the process for return or replacement of MJD31CAJ?
All MJD31CAJ units undergo pre-shipment inspection (PSI). If there is an issue with MJD31CAJ, 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 MJD31CAJ part is unused and in its original packaging.
Return procedure for MJD31CAJ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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