My Inquiry
My Account
onsemi MMBT3904TT1
- Part No.:
- MMBT3904TT1
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- -
- Datasheet:
-
MMBT3904TT1.pdf
- Description:
- TRANS NPN 40V 200MA SOT416
- Quantity:
- Payment:
- Shipping:
Inventory:3,894
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MMBT3904TT1 from onsemi is an NPN silicon general-purpose amplifier transistor in SOT-416/SC-75 package, rated for 40 VCEO, 200 mAC, and 300 MHz fT, used in low-power signal amplification and switching circuits in portable electronics and sensor interfaces.
For engineers reviewing the MMBT3904TT1 datasheet, pinout, applications, or equivalent options, key selection criteria include VCEO/IC rating, SOT-416 thermal performance (RJA = 400–600 °C/W), hFE variation across IC, and Pb-free RoHS-compliant packaging for surface-mount assembly.
Technical Context
This device operates as a discrete bipolar junction transistor with fixed NPN polarity, optimized for linear amplification and saturated switching. Its hFE ranges from 40 to 300 depending on collector current (0.1–100 mA), and it delivers VCE(sat) ≤ 0.3 V at IC = 50 mA / IB = 5 mA.
Thermal design relies on FR-4 board mounting: PD = 300 mW with 1.0 × 1.0 inch copper pad (derated 2.4 mW/°C above 25°C), yielding RJA = 400 °C/W - critical for thermally constrained PCB layouts in space-constrained applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 40 Vdc - maximum safe collector-emitter voltage before breakdown; defines upper rail limit in amplifier stages. |
| IC (max) | 200 mAdc - continuous DC collector current handling; sets usable output drive capability. |
| fT | 300 MHz - unity-gain bandwidth; supports RF preamp and high-speed digital switching up to ~30 MHz. |
| hFE @ 10 mA | 100–300 - DC current gain at mid-range bias; determines base drive requirements for saturation. |
| VCE(sat) | 0.2–0.3 V - low saturation voltage at IC/IB = 10; minimizes power loss in switch-mode operation. |
| Cobo | ≤ 4.0 pF - output capacitance at 5 V reverse bias; impacts high-frequency stability and bandwidth roll-off. |
| RJA (1.0″ pad) | 400 °C/W - junction-to-ambient thermal resistance with standard copper area; informs derating for ambient >25°C. |
Pinout & Package
SOT-416/SC-75 (Case 463, Style 1) is a 3-pin, ultra-small surface-mount plastic package (1.60 × 0.80 × 0.80 mm, 1.00 mm pitch), optimized for automated placement and low thermal mass in compact consumer and IoT PCBs.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Base | Current-controlled input node; requires series resistor to limit IB and ensure hFE-based IC scaling. |
| 2 | Emitter | Common reference terminal for NPN configuration; tied to ground or low-impedance return path in most topologies. |
| 3 | Collector | Output current sink node; connects to load or pull-up resistor; voltage swing limited by VCEO = 40 V. |
Key Features
| Feature | Design Value |
|---|---|
| Pb-free, Halogen-free, RoHS-compliant | Meets global environmental compliance mandates without requiring special soldering profiles or exemptions. |
| AEC-Q101 qualified (S-prefix variants) | Validated for automotive-grade reliability; MMBT3904TT1G meets stress test requirements for temperature cycling, HTRB, and ESD. |
| Low-profile SOT-416 package | Enables <1.3 mm² PCB footprint and <0.8 mm height - suitable for wearables, hearing aids, and stacked modules. |
| High fT / low Cibo combination | Supports stable small-signal amplification up to 100 MHz with minimal Miller effect distortion. |
| Wide hFE range (40–300) | Accommodates production spread while maintaining functional margin in bias networks designed for hFE ≥ 100. |
Applications
| Portable Audio Amplifiers | LED Driver Switches |
|---|---|
|
Use Scenario: Low-voltage headphone driver stage in Bluetooth earbuds with 3.3 V supply and 16 Ω load. IC Role / Device Role / Timing Role: NPN small-signal amplifier configured in common-emitter topology to deliver 10–20 mW output power. Use Value: VCE(sat) ≤ 0.3 V and hFE ≥ 100 at 10 mA enable efficient gain staging with minimal quiescent loss and THD <1%. |
Use Scenario: Constant-current LED backlight control in smartwatch displays using PWM dimming at 1–5 kHz. IC Role / Device Role / Timing Role: Saturated switch driving 20 mA LED string from 3.3 V rail with fast turn-on/turn-off (<35 ns). Use Value: td/tr ≤ 35 ns and VBE(sat) ≤ 0.85 V ensure clean PWM edges and <0.5% duty-cycle error at 5 kHz. |
| IoT Sensor Signal Conditioning | USB-C Power Path Control |
|
Use Scenario: Amplifying microvolt-level thermistor or photodiode signals in battery-powered environmental sensors. IC Role / Device Role / Timing Role: Low-noise preamplifier stage with 1 kΩ source impedance and 1 kHz bandwidth. Use Value: NF ≤ 5.0 dB at IC = 100 μA and RS = 1 kΩ enables sub-10 μV/√Hz input-referred noise performance. |
Use Scenario: Reverse-polarity protection and load-switch control in USB-C power delivery modules. IC Role / Device Role / Timing Role: Discrete NPN driver controlling gate of external P-MOSFET in high-side power switch configuration. Use Value: VCEO = 40 V and IC = 200 mA support 20 V max VIN and 1 A switched load with robust fault margin. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar NPN general-purpose transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BC846B,215 | Same SOT-23 package (larger than SOT-416); hFE = 200–450 @ 10 mA; VCEO = 65 V; fT = 100 MHz. | Higher voltage headroom but lower bandwidth; less suitable for >50 MHz signal paths. | Select when board layout allows SOT-23 and higher VCEO margin is prioritized over size or speed. |
| PN2222A-AP | SOT-23 package; VCEO = 40 V; IC = 600 mA; fT = 250 MHz; hFE = 100–300 @ 150 mA. | Higher current capacity but larger die and thermal mass; not optimized for ultra-low-power bias. | Choose when driving loads >100 mA or requiring higher surge tolerance in industrial controls. |
Compared with BC846B,215 and PN2222A-AP, the MMBT3904TT1 offers superior size efficiency (SOT-416), best-in-class fT/Cobo ratio for RF-sensitive designs, and tighter thermal resistance control on minimal copper - making it optimal for miniaturized, battery-critical systems where layout area and high-frequency fidelity matter.
Availability
MMBT3904TT1 is available at Aetrix Electronics and suitable for portable audio amplifiers, LED driver switches, IoT sensor signal conditioning, and USB-C power path control requiring stable component supply across high-mix, low-volume production runs.
Supply support for MMBT3904TT1 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 MMBT3904TT1 belongs to onsemi's general-purpose bipolar transistor product line, engineered for cost-effective, reliable amplification and switching in space-constrained, low-power electronic systems.
FAQ
What is the maximum collector current rating for MMBT3904TT1?
The MMBT3904TT1 has a maximum continuous collector current (IC) rating of 200 mAdc at TA = 25°C. Derating applies above 25°C per the thermal characteristics table: 2.4 mW/°C with 1.0 × 1.0 inch FR-4 copper pad. Exceeding this limit risks thermal runaway and permanent degradation of hFE and VCE(sat). The MMBT3904TT1 must be operated within its SOA boundaries defined in the datasheet's Safe Operating Area graph.
Is MMBT3904TT1 RoHS-compliant and lead-free?
Yes, the MMBT3904TT1G variant is explicitly marked as Pb-free, halogen-free, and RoHS-compliant per onsemi's documentation. The "G" suffix denotes lead-free packaging, and the device meets EU RoHS Directive 2011/65/EU requirements. No exemption codes apply, and the material composition is verified through onsemi's certified supply chain and third-party testing reports.
What is the pin configuration of MMBT3904TT1 in the SOT-416 package?
The MMBT3904TT1 uses SOT-416 (SC-75) Case 463 Style 1 pinout: Pin 1 = Base, Pin 2 = Emitter, Pin 3 = Collector. This configuration is confirmed in the official onsemi datasheet (MMBT3904TT1/D, Rev. 7, October 2024), Figure "MARKING DIAGRAM" and mechanical outline drawing. Incorrect orientation during placement will result in circuit failure due to reversed polarity.
How does the thermal performance of MMBT3904TT1 compare between minimum pad and 1.0 × 1.0 inch pad layouts?
The MMBT3904TT1 achieves PD = 200 mW with RJA = 600 °C/W on minimum FR-4 pad, but improves to PD = 300 mW with RJA = 400 °C/W on 1.0 × 1.0 inch pad. This 50% power increase and 33% thermal resistance reduction directly impact reliability: at 100 mW dissipation, junction temperature rise drops from 60°C to 40°C - critical for long-term stability in sealed enclosures.
Can MMBT3904TT1 replace the legacy 2N3904 in new designs?
The MMBT3904TT1 is the SOT-416 surface-mount equivalent of the through-hole 2N3904, sharing identical electrical specifications (VCEO, hFE, fT, etc.) but differing in package, pinout, and thermal behavior. It is not a drop-in replacement due to SOT-416 vs. TO-92 mechanical incompatibility; redesign of footprint and revalidation of thermal margins are required. The MMBT3904TT1 is intended for new SMT designs, not retrofits.
MMBT3904TT1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- *
- Package/Case:
- -
- Packaging:
- Cut Tape (CT)
- Product Status:
- Obsolete
- Transistor Type:
- -
- Current - Collector (Ic) (Max):
- -
- Voltage - Collector Emitter Breakdown (Max):
- -
- Vce Saturation (Max) @ Ib, Ic:
- -
- Current - Collector Cutoff (Max):
- -
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- -
- Power - Max:
- -
- Frequency - Transition:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- -
- Supplier Device Package:
- -
MMBT3904TT1 FAQ
1.How can I place an order for MMBT3904TT1 through Aetrix?
Please submit a Request for Quotation (RFQ) for MMBT3904TT1 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 MMBT3904TT1 reliable?
The price and inventory of MMBT3904TT1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMBT3904TT1 is usually 5 days.
3.What payment methods are accepted for MMBT3904TT1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMBT3904TT1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMBT3904TT1?
MMBT3904TT1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMBT3904TT1 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 MMBT3904TT1?
For technical support, including MMBT3904TT1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMBT3904TT1 requirements.
6.How does Aetrix verify that MMBT3904TT1 is sourced from the original manufacturer or authorized distributors?
All MMBT3904TT1 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 MMBT3904TT1 meets industry standards.
7.What is the process for return or replacement of MMBT3904TT1?
All MMBT3904TT1 units undergo pre-shipment inspection (PSI). If there is an issue with MMBT3904TT1, 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 MMBT3904TT1 part is unused and in its original packaging.
Return procedure for MMBT3904TT1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MMBT3904TT1 Tags
-
MMBT3906LT1G
onsemi
-
MMBT3904-7-F
Diodes Incorporated
-
MMBT3904LT1G
onsemi
-
MMBT3906-7-F
Diodes Incorporated
-
MMBT3904-TP
Micro Commercial Co
-
MMBT2222A-7-F
Diodes Incorporated
-
BC846BLT1G
onsemi
-
BC847B,215
Nexperia USA Inc.
-
SMMBT3904LT1G
onsemi
-
MMBT2222A-TP
Micro Commercial Co
-
MMBTA06LT1G
onsemi
-
MMBT2222ALT1G
onsemi
Tech Hub
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
