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onsemi MJK31CTWG
- Part No.:
- MJK31CTWG
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- SOT-1023, 4-LFPAK
- Datasheet:
-
MJK31CTWG.pdf
- Description:
- TRANS NPN 100V 3A LFPAK4
- Quantity:
- Payment:
- Shipping:
Inventory:2,964
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Product details
Overview
MJK31CTWG from onsemi is an NPN bipolar junction transistor designed for general-purpose power switching and amplification in automotive and industrial systems. It delivers 100 VCEO, 3 A continuous collector current, and 1.2 VCE(sat) at IC = 3 A / IB = 0.375 A, housed in the thermally enhanced LFPAK4 (5 × 6 mm) package. It is used in airbag deployment circuits, powertrain control units, and instrument cluster drivers.
For engineers reviewing the MJK31CTWG datasheet, pinout, applications, or equivalent options, key selection criteria include VCEO = 100 V, IC = 3 A, RJC = 2.4 °C/W, AEC−Q101 qualification, and LFPAK4 thermal performance in high-reliability automotive power stages.
Technical Context
This NPN power transistor operates in linear and saturated switching modes with DC current gain (hFE) ranging from 10 to 60 at IC = 1–3 A and VCE = 4 V. Its fT of 3 MHz supports moderate-speed switching in DC-DC converters and motor drivers.
The device features low thermal resistance (RJC = 2.4 °C/W) due to its copper-clip LFPAK4 construction, enabling efficient heat transfer from die to PCB pad. It is rated for junction temperatures from −65 °C to +150 °C and supports peak collector current up to 5 A.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 100 V - Maximum sustainable collector-emitter voltage before breakdown under open-base conditions; defines safe operating voltage ceiling in switching applications. |
| IC (continuous) | 3 A - Continuous DC collector current capability at TA = 25 °C; sets baseline load-handling capacity for regulators and drivers. |
| VCE(sat) | 1.2 V - Saturation voltage at IC = 3 A and IB = 0.375 A; directly determines conduction loss and power dissipation in switch-mode operation. |
| RJC | 2.4 °C/W - Junction-to-case thermal resistance; enables high-power density mounting on FR4 with 6 cm² 2 oz. Cu pad without external heatsink. |
| fT | 3 MHz - Gain-bandwidth product at IC = 0.5 A, VCE = 10 V; limits usable switching frequency in analog amplifiers and PWM-controlled loads. |
| hFE | 10–60 - DC current gain range across IC = 1–3 A; informs base drive design margin and stability in linear regulator feedback paths. |
| TJ range | −65 to +150 °C - Operating junction temperature window; supports under-hood automotive environments and industrial ambient extremes. |
Pinout & Package
Package: LFPAK4 (Case 760AB), surface-mount, 4-terminal copper-clip construction (5 mm × 6 mm footprint), optimized for thermal conduction and low-inductance switching.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Emitting terminal for majority carriers | Low-impedance connection to emitter node; internally bonded to large-area copper clip for minimal parasitic inductance and thermal path. |
| 2 (Collector) | Current-sinking output terminal | Main power output path; electrically and thermally connected to exposed copper drain pad on bottom side of package. |
| 3 (Base) | Control input for transistor biasing | Enables turn-on/turn-off via base current; requires ≥0.375 A drive for full saturation at 3 A collector load. |
| 4 (Collector) | Second collector terminal (parallel) | Dual-collector configuration reduces on-resistance and improves current sharing; critical for thermal derating at high duty cycles. |
Key Features
| Feature | Design Value |
|---|---|
| AEC−Q101 qualified | Validated for automotive powertrain and safety-critical modules including airbag deployment systems. |
| LFPAK4 thermal performance | RJC = 2.4 °C/W enables >2.7 W dissipation at TA = 25 °C without heatsink on standard FR4. |
| Complementary PNP pair | MJK32C provides matched switching characteristics for H-bridge and push-pull topologies. |
| Pb-free, halogen-free | RoHS-compliant construction meets automotive ELV and industrial environmental compliance requirements. |
| High VCEO/IC ratio | 100 V / 3 A rating supports 24 V and 48 V system designs with robust voltage headroom against transients. |
Applications
| Automotive Airbag Deployment | Engine Control Unit (ECU) Driver |
|---|---|
Use Scenario: High-current pulse triggering of squib igniters during crash events. IC Role / Device Role / Timing Role: NPN power switch controlling squib current path with fast turn-on and low saturation loss. Use Value: VCEO = 100 V withstands battery+load-dump transients; RJC = 2.4 °C/W ensures reliable pulsed operation without thermal runaway. | Use Scenario: Driving solenoid valves and fuel injectors in gasoline/diesel engine management. IC Role / Device Role / Timing Role: Low-side switching element in injector driver stage with controlled current ramp and clamping. Use Value: IC = 3 A continuous and ICM = 5 A peak support multi-millisecond injection pulses; AEC−Q101 ensures field reliability. |
| Instrument Cluster Backlight Driver | Industrial DC-DC Converter Switch |
Use Scenario: Regulated current source for LED backlight arrays in automotive dashboards. IC Role / Device Role / Timing Role: Linear or PWM-controlled current sink regulating LED string current. Use Value: hFE = 10–60 allows stable closed-loop current control; TJ = −65 to +150 °C accommodates dashboard temperature extremes. | Use Scenario: Main switching transistor in non-isolated buck converter for industrial 24 V rail generation. IC Role / Device Role / Timing Role: High-efficiency power switch operating at ≤3 MHz with low VCE(sat) conduction loss. Use Value: fT = 3 MHz and VCE(sat) = 1.2 V enable >90% efficiency at 500 kHz switching with minimal gate drive overhead. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STN3PF10 | 100 V, 3.5 A, TO-220FP package; RJA = 60 °C/W vs. MJK31CTWG's 45 °C/W; no AEC−Q101 qualification. | Non-automotive industrial use only; unsuitable for airbag or ECU due to lack of automotive qualification and higher thermal resistance. | Select when cost-sensitive non-automotive switching is needed and board-level heatsinking is available. |
| ZXTN2012E6TA | 100 V, 3 A, SOT-23 package; hFE = 100–300; RJA = 200 °C/W; not AEC−Q101 qualified. | Limited to low-power signal switching; cannot sustain 3 A continuous due to thermal limitations in small-outline package. | Use only for low-duty-cycle, low-current bias or logic-level interface-not for power switching. |
Compared with STN3PF10 and ZXTN2012E6TA, the MJK31CTWG uniquely combines AEC−Q101 qualification, LFPAK4 thermal performance (RJC = 2.4 °C/W), and 3 A continuous rating-making it the only viable option for space-constrained, high-reliability automotive power stages requiring zero heatsink.
Availability
MJK31CTWG is available at Aetrix Electronics and suitable for automotive airbag systems, engine control units, and industrial DC-DC converters requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.
Supply support for MJK31CTWG 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
onsemi is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.
The MJK31CTWG belongs to onsemi's automotive-qualified NPN power transistor family, engineered specifically for high-reliability, thermally demanding power switching in safety-critical vehicle subsystems.
FAQ
What is the maximum continuous collector current rating for MJK31CTWG?
The MJK31CTWG is rated for 3 A continuous collector current (IC) at TA = 25 °C. This rating assumes proper PCB layout with a 6 cm², 2 oz. copper collector pad. Derating applies above 25 °C ambient per the power derating curve in Figure 8 of the official datasheet. The MJK31CTWG also supports 5 A peak collector current (ICM) for short-duration pulses.
Is MJK31CTWG qualified for automotive applications?
Yes, the MJK31CTWG carries AEC−Q101 qualification and PPAP capability, confirmed in the onsemi datasheet. It is explicitly intended for automotive end applications including airbag deployment, powertrain control units, and instrument clusters. The NJV prefix in the ordering code NJVMJK31CTWG further denotes automotive-specific site and control change requirements.
What package type does MJK31CTWG use and why is it significant?
The MJK31CTWG uses the LFPAK4 (Case 760AB) package - a 4-terminal, surface-mount copper-clip construction measuring 5 mm × 6 mm. Its significance lies in RJC = 2.4 °C/W, which enables superior thermal conduction versus traditional SO-8 or DPAK packages. This allows the MJK31CTWG to dissipate up to 2.7 W without external heatsinking in automotive-grade layouts.
Does MJK31CTWG have a complementary PNP transistor?
Yes, the MJK32C is the manufacturer-specified complementary PNP transistor for the MJK31CTWG. Both devices share identical voltage, current, and thermal ratings, and are designed for matched performance in push-pull, H-bridge, and dual-rail power amplifier configurations. Their shared LFPAK4 packaging ensures consistent thermal and mechanical behavior on PCBs.
What is the saturation voltage VCE(sat) of MJK31CTWG under full-load conditions?
The MJK31CTWG exhibits a maximum VCE(sat) of 1.2 V when operated at IC = 3 A and IB = 0.375 A, per the Electrical Characteristics table. This low saturation voltage minimizes conduction losses in switching applications such as DC-DC converters and solenoid drivers, directly improving system efficiency and reducing thermal stress on the MJK31CTWG itself.
MJK31CTWG Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- SOT-1023, 4-LFPAK
- 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):
- 50µA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 25 @ 1A, 4V
- Power - Max:
- 2.7 W
- Frequency - Transition:
- 3MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- LFPAK4 (5x6)
MJK31CTWG FAQ
1.How can I place an order for MJK31CTWG through Aetrix?
Please submit a Request for Quotation (RFQ) for MJK31CTWG 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 MJK31CTWG reliable?
The price and inventory of MJK31CTWG are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MJK31CTWG is usually 5 days.
3.What payment methods are accepted for MJK31CTWG?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MJK31CTWG transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MJK31CTWG?
MJK31CTWG orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MJK31CTWG 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 MJK31CTWG?
For technical support, including MJK31CTWG datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MJK31CTWG requirements.
6.How does Aetrix verify that MJK31CTWG is sourced from the original manufacturer or authorized distributors?
All MJK31CTWG 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 MJK31CTWG meets industry standards.
7.What is the process for return or replacement of MJK31CTWG?
All MJK31CTWG units undergo pre-shipment inspection (PSI). If there is an issue with MJK31CTWG, 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 MJK31CTWG part is unused and in its original packaging.
Return procedure for MJK31CTWG:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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