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Diodes Incorporated FMMT494TA
- Part No.:
- FMMT494TA
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Bipolar Transistors
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
FMMT494TA.pdf
- Description:
- TRANS NPN 120V 1A SOT-23-3
- Quantity:
- Payment:
- Shipping:
Inventory:7,836
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Product details
Overview
FMMT494TA from Diodes Incorporated is a 120V, 1A NPN silicon planar medium-power transistor in SOT23 (Type DN) package, characterized for high-current gain up to 1A with hFE ≥20 at IC = 1A, VCE = 10V, and featuring 500mW power dissipation and AEC-Q101 qualification for automotive-grade reliability. It serves as a robust switching or linear amplification device in DC-DC converters, LED drivers, and industrial control interfaces requiring high breakdown voltage and pulse current capability.
For engineers reviewing the FMMT494TA datasheet, FMMT494TA pinout, FMMT494TA application, or FMMT494TA equivalent, key selection considerations include its 120V VCEO rating, 2A ICM peak pulse current, SOT23 thermal resistance (RθJA = 250°C/W), hFE performance across 1mA–1A bias range, and AEC-Q101 qualification status for harsh-environment deployment.
Technical Context
This NPN bipolar junction transistor operates in active, saturation, and cutoff regions with defined safe operating area (SOA) limits up to 120V and 1A DC, validated under pulsed conditions (≤300µs, ≤2% duty cycle) for VCE(sat), hFE, and fT measurements. Its 100MHz transition frequency and low output capacitance (Cobo ≤10pF) support moderate-speed switching in power management stages.
The device uses planar epitaxial construction with green molding compound (UL 94V-0), matte tin-plated leads, and achieves ESD robustness of 4kV HBM - enabling stable operation in PCB-level transient environments without external protection in many applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 120 V - Maximum collector-emitter voltage before breakdown; enables use in 48V+ bus systems and flyback snubbers. |
| IC (cont.) | 1 A - Continuous collector current rating; supports sustained load switching in relay drivers and motor gate buffers. |
| ICM | 2 A - Peak pulse current capability; accommodates inrush or surge events in power supply startup sequences. |
| hFE @ 1A | ≥20 - Minimum DC current gain at full rated current; ensures reliable base drive sizing for saturation in high-current switches. |
| VCE(sat) @ 500mA | ≤300 mV - Low saturation voltage reduces conduction loss and self-heating during on-state operation. |
| fT | 100 MHz - Transition frequency confirms usable bandwidth for PWM frequencies up to ~10–20 MHz with adequate gain margin. |
| RθJA | 250 °C/W - Junction-to-ambient thermal resistance on 15×15mm FR4 with 1oz copper; defines maximum ambient temperature for 500mW operation. |
Pinout & Package
SOT23 (Type DN) surface-mount package with 3-terminal configuration: compact footprint (3.0 × 2.42 × 1.12 mm), matte tin-plated leads, UL 94V-0 flammability rating, and moisture sensitivity level 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Current sink terminal | Reference node for base-emitter bias; connects to ground or low-side return path in common-emitter configurations. |
| 2 (Base) | Control input | Receives forward-biased current to modulate collector current; requires series resistor to limit IB ≤200mA per absolute max rating. |
| 3 (Collector) | Current source terminal | Connects to load or supply rail; handles full switched current and must be routed with adequate copper area for thermal relief. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive-grade temperature cycling, humidity, and mechanical stress - suitable for under-hood ECUs and body control modules. |
| High VCEO (120V) | Enables direct interface with 48V/60V industrial buses and telecom power rails without cascaded voltage clamping. |
| hFE characterized to 1A | Guaranteed minimum gain at full-rated current simplifies base drive design and eliminates guesswork in high-load saturation. |
| Green, halogen-free construction | Meets RoHS 2 and JEDEC J-STD-020 Level 1 standards - supports environmentally compliant manufacturing and long-term supply chain sustainability. |
| Low RθJL (197°C/W) | Junction-to-lead thermal resistance allows efficient heat transfer to PCB copper via collector pad - critical for sustained 500mW operation. |
Applications
| Industrial Power Switching | Automotive Load Control |
|---|---|
Use Scenario: Driving solenoids, relays, and small DC motors in programmable logic controllers and factory automation I/O modules. IC Role / Device Role / Timing Role: Medium-power NPN switch operating in saturation mode with 1A continuous load current and fast turn-on/turn-off transitions. Use Value: 120V VCEO withstands inductive kickback from 24V/48V coils; 2A ICM absorbs energy during de-energization without snubber circuitry. | Use Scenario: Controlling lighting loads (headlamps, interior LEDs) and HVAC actuators in body electronics modules. IC Role / Device Role / Timing Role: High-reliability load switch with AEC-Q101 qualification, handling repetitive 100ms–500ms pulses at ambient temperatures up to +125°C. Use Value: Guaranteed hFE ≥20 at 1A ensures consistent base drive margin across temperature and lifetime; green packaging meets OEM environmental requirements. |
| DC-DC Converter Auxiliary Switch | LED Constant-Current Driver |
Use Scenario: Secondary-side synchronous rectifier or gate driver enable switch in isolated flyback and forward converters. IC Role / Device Role / Timing Role: Fast-switching NPN used in low-duty-cycle, high-voltage clamp or reset paths with 100MHz fT supporting >1MHz switching. Use Value: 10pF Cobo minimizes capacitive loading on control nodes; 250°C/W RθJA allows thermal integration into compact converter layouts. | Use Scenario: Linear current regulation for high-brightness LED strings in signage and architectural lighting. IC Role / Device Role / Timing Role: Adjustable constant-current sink configured with emitter resistor feedback and base bias network. Use Value: Tight VCE(sat) spec (≤300mV @ 500mA) maintains <5% current error over temperature; 500mW PD supports 350mA–500mA LED drive without heatsink. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN medium-power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ZXTN2010Z | VCEO = 100V (vs. 120V); hFE min = 100 @ 500mA (vs. 60 @ 500mA); RθJA = 200°C/W | Lacks AEC-Q101 qualification; optimized for higher gain at mid-current, not high-voltage hold-up | Prefer when gain stability at 100–500mA dominates over 120V breakdown or automotive compliance. |
| MMBT4401 | VCEO = 40V; IC = 600mA; PD = 310mW; no AEC-Q101 rating | Not suitable for >48V systems or automotive under-hood use; lower thermal capability | Select only for cost-sensitive, low-voltage (<24V), non-automotive consumer applications where 120V headroom is unnecessary. |
Compared with ZXTN2010Z and MMBT4401, FMMT494TA uniquely delivers 120V standoff, AEC-Q101 validation, and guaranteed hFE down to 1A - making it the only choice among the three for 48V+ industrial switching and automotive body control where voltage margin and reliability are non-negotiable.
Availability
FMMT494TA is available at Aetrix Electronics and suitable for industrial power switching, automotive load control, DC-DC converter auxiliary functions, and LED constant-current driver designs requiring stable component supply and long-term lifecycle assurance.
Supply support for FMMT494TA 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for automotive, industrial, and computing markets with ISO/TS 16949 and ISO 14001 certifications.
The FMMT494TA belongs to Diodes' AEC-Q101-qualified medium-power transistor product line, engineered specifically for high-voltage switching and ruggedized control in harsh-environment electronic systems.
FAQ
What is the maximum allowable base current for continuous operation?
The absolute maximum base current (IB) is 200 mA per the datasheet's Absolute Maximum Ratings table. For reliable continuous operation, IB should be limited to ≤100 mA to avoid thermal overstress and ensure long-term junction integrity, especially when IC approaches 1 A and ambient temperature exceeds 70°C.
Does FMMT494TA require a heatsink in standard SOT23 mounting?
No external heatsink is required for FMMT494TA under typical conditions: at 500 mW dissipation on a 15 mm × 15 mm FR4 board with 1 oz copper, junction temperature remains within −55°C to +150°C limits. However, thermal relief via increased copper area on the collector pad is strongly recommended to maintain RθJA near the specified 250°C/W.
How does the AEC-Q101 qualification impact PCB layout practices?
AEC-Q101 qualification confirms robustness against thermal cycling, vibration, and humidity - but does not relax layout requirements. Designers must still observe minimum creepage/clearance (≥0.5 mm) between collector and emitter pads, avoid solder mask dams over thermal pads, and use IPC-7351-compliant SOT23 (DN) footprints to ensure mechanical reliability during reflow and board flexure.
Can FMMT494TA replace FMMT494Q in non-automotive applications?
Yes - FMMT494TA and FMMT494Q share identical electrical and thermal specifications; the "Q" suffix denotes an automotive-specific datasheet and traceability documentation. In non-automotive applications, FMMT494TA offers identical performance with broader commercial availability and simplified compliance reporting.
FMMT494TA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 1 A
- Voltage - Collector Emitter Breakdown (Max):
- 120 V
- Vce Saturation (Max) @ Ib, Ic:
- 300mV @ 50mA, 500mA
- Current - Collector Cutoff (Max):
- 100nA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 100 @ 250mA, 10V
- Power - Max:
- 500 mW
- Frequency - Transition:
- 100MHz
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3
FMMT494TA FAQ
1.How can I place an order for FMMT494TA through Aetrix?
Please submit a Request for Quotation (RFQ) for FMMT494TA 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 FMMT494TA reliable?
The price and inventory of FMMT494TA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for FMMT494TA is usually 5 days.
3.What payment methods are accepted for FMMT494TA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for FMMT494TA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for FMMT494TA?
FMMT494TA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your FMMT494TA 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 FMMT494TA?
For technical support, including FMMT494TA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your FMMT494TA requirements.
6.How does Aetrix verify that FMMT494TA is sourced from the original manufacturer or authorized distributors?
All FMMT494TA 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 FMMT494TA meets industry standards.
7.What is the process for return or replacement of FMMT494TA?
All FMMT494TA units undergo pre-shipment inspection (PSI). If there is an issue with FMMT494TA, 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 FMMT494TA part is unused and in its original packaging.
Return procedure for FMMT494TA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
FMMT494TA Tags
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