MMBT3904-7-F - 40V NPN Small Signal BJT 200mA SOT-23 | Diodes Inc
Teilenummer: MMBT3904-7-F ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $0.18 | $0,18 |
| 10 | $0.14 | $1,40 |
| 100 | $0.09 | $9,00 |
| 500 | $0.07 | $35,00 |
| 1.000 | $0.05 | $50,00 |
| 3.000 | $0.04 | $120,00 |
MMBT3904-7-F Übersicht
A bipolar junction transistor is a three-terminal semiconductor device in which a small base current controls a larger collector current; NPN BJTs use a p-type base sandwiched between two n-type regions, allowing electrons (rather than holes) to be the primary charge carrier, which gives NPN devices superior high-frequency performance for most analog switching and amplification tasks. The MMBT3904-7-F sits within the broader category hierarchy of BJT -> bipolar transistor -> discrete semiconductor, and is one of the most widely second-sourced active components in the industry.
Key specifications of the MMBT3904-7-F include VCEO of 40 V, VCBO of 40 V, VEBO of 6 V, DC current gain (hFE) of 100 to 300 at 10 mA, transition frequency (fT) of 300 MHz minimum, and total power dissipation of 300 mW. The complementary PNP type is the MMBT3906-7-F from the same Diodes Incorporated family, enabling matched complementary designs. The device is fully RoHS compliant, lead-free, and halogen/antimony-free per the manufacturer datasheet.
The MMBT3904-7-F uses an epitaxial planar die construction, which provides tight parametric distribution and stable DC gain across the operating temperature range of -55C to +150C. Compared to the older through-hole 2N3904, the MMBT3904-7-F integrates identical electrical characteristics into the much smaller SOT-23 footprint, enabling high-density PCB layouts while remaining a drop-in functional replacement for any circuit designed around the 2N3904.
Typical applications include general-purpose switching circuits, signal amplification stages in audio and instrumentation front-ends, MOSFET gate drivers in low-power converters, level shifters between logic domains, oscillator and timer circuits, and LED driver stages. The 300 MHz fT also makes the part suitable for low-frequency RF amplification and IF stages up to a few tens of MHz.
When designing with the MMBT3904-7-F, ensure that the collector current does not exceed 200 mA continuous and that power dissipation stays within the 300 mW SOT-23 limit (derate above 25C ambient). A base resistor sized to provide roughly 1/10th of the desired collector current guarantees saturation in switching applications.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, giving engineers a single decision-ready reference for component selection and sourcing.
Drop-in-Alternativen für MMBT3904-7-F – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Varianten dieser Serie
Modelle derselben Serie, die drop-in-kompatibel sind mit MMBT3904-7-F (gleiche Bauform und Footprint) – abweichend in DC Current Gain (hFE), Transition Frequency (fT), Collector-Base Voltage (VCBO), Transistor Type, Collector-Emitter Saturation Voltage (VCE(sat)).
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
MMBT3904-13-F
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MMBT3904LP-7
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MMBT3904LT1G
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
SMMBT3904
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MMBT3904LT3G
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MMST3904-7-F
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MMBT3904-7-F Grenzwerte & elektrische Eigenschaften
| Transistortyp | NPN Bipolar Junction Transistor (BJT) |
| Kollektor-Emitter-Spannung (Vceo) | 40 V |
| Kollektor-Basis-Spannung (Vcbo) | 40 V |
| Emitter-Basis-Spannung (Vebo) | 6 V |
| Continuous Collector Current (IC) | 200 mA |
| Power Dissipation (PD) | 300 mW |
| Übergangsfrequenz (ft) | 300 MHz minimum |
| DC Current Gain (hFE) | 100 to 300 @ IC=10 mA, VCE=1 V |
| Kollektor-Emitter-Sättigungsspannung (Vce(sat)) | 200 mV typical @ IC=10 mA |
| Betriebstemperaturbereich | -55 C to +150 C |
| Gehäuse / Bauform | SOT-23-3 |
| Montageart | Surface Mount |
| Die Construction | Epitaxial Planar |
| Complementary PNP Type | MMBT3906-7-F |
| RoHS Compliance | Yes (Lead-Free, Halogen-Free, Antimony-Free) |
MMBT3904-7-F Pin-Konfiguration
| Pin 1 | Emitter — Emitter terminal (NPN) |
| Pin 2 | Base — Base control terminal |
| Pin 3 | Collector — Collector terminal (NPN) |
Typische Anwendungen
MMBT3904-7-F ist geeignet für 6 Anwendungs: General-Purpose Switching Circuits, Signal Amplification in Audio Front-Ends, MOSFET Gate Driver Stage, Logic Level Shifter / Voltage Translator, Oscillator and Timer Circuits, LED Driver and Indicator Circuits.
General-Purpose Switching Circuits
The MMBT3904-7-F is widely deployed as a low-side switch for loads under 200 mA, including LEDs, relays (with base-driver), optocouplers, and logic-level translation between 3.3 V and 5 V domains. With a VCE(sat) of 200 mV at 10 mA and 300 mW dissipation, it cleanly saturates when base-driven at roughly 1/10th of the desired collector current. Engineers value its simple drive requirements, fast switching at low currents, and the industry-standard SOT-23 footprint that allows drop-in placement across countless reference designs sourced from DigiKey, Mouser, and open-source hardware.
Empfohlen
Signal Amplification in Audio Front-Ends
The MMBT3904-7-F serves as a low-cost general-purpose amplifier in audio preamp and instrumentation front-end stages, where its 300 MHz fT and 100-300 hFE support low-distortion small-signal gain up to several tens of MHz. While not optimized for ultra-low-noise audio (the BC847B is preferred for lowest noise figure), the MMBT3904-7-F delivers adequate performance for line-level stages, microphone preamps, and tone-control circuitry. Its tight hFE distribution simplifies DC biasing and yields predictable gain across production builds.
Empfohlen
MOSFET Gate Driver Stage
The MMBT3904-7-F is commonly used as a low-side NPN driver for power MOSFET gates in DC-DC converters, motor drivers, and relay switching circuits. Its 200 mA collector current can source/sink gate charge for small MOSFETs directly, while for larger FETs it serves as the first stage of a Darlington or totem-pole driver. The 6 V VEBO rating is well above typical 12 V gate-drive requirements, and the fast transition frequency enables sub-microsecond switching transitions at moderate loads.
Empfohlen
Logic Level Shifter / Voltage Translator
The MMBT3904-7-F implements simple, low-cost level shifting between logic domains operating at different voltages (e.g., 3.3 V to 5 V or 5 V to 12 V). Configured in common-emitter or emitter-follower topology with base pull-up to the lower-voltage rail, it provides bidirectional translation with minimal propagation delay. The SOT-23 footprint allows integration directly next to microcontrollers and ASICs where board space is constrained, and the wide operating temperature range supports industrial applications.
Empfohlen
Oscillator and Timer Circuits
The MMBT3904-7-F is a proven building block in classic astable and monostable multivibrator circuits, RC oscillators, and 555-timer replacement designs. Its 300 MHz fT comfortably exceeds the frequencies used in sub-MHz oscillators, and its predictable hFE range enables stable timing across temperature. Designers choose it for low-cost waveform generators, pulse-forming networks, and simple clock sources in microcontroller-based systems where precise frequency is not required.
Empfohlen
LED Driver and Indicator Circuits
The MMBT3904-7-F drives indicator LEDs, optocoupler inputs, and 7-segment display segments in current-limited sink or source configurations. A single base resistor sets the LED current to typically 10-20 mA while maintaining headroom for the collector-emitter path. The SOT-23 footprint and 200 mA rating cover most discrete indicator and small-display applications, while the complementary MMBT3906-7-F enables matched PNP-NPN driver pairs for higher-side sourcing and lower-side sinking within the same PCB area.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für MMBT3904-7-F – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | MMBT3904-13-F | MMBT3904LP-7 | MMBT3904LT1G | SMMBT3904 | MMBT3904LT3G | MMST3904-7-F |
|---|---|---|---|---|---|---|---|
| Brand | Diodes Incorporated | Diodes Incorporated | Diodes Incorporated | onsemi | Nexperia | onsemi | Diodes Incorporated |
| Package | SOT-23-3 | SOT-23-3 (same) | SOT-23-3 (same) | SOT-23-3 (same) | SOT-23-3 (same) | SOT-23-3 (same) | SOT-23-3 (same, SOT-323 variant) |
| Transistor Type | NPN | NPN | NPN | NPN | NPN | NPN | NPN |
| VCEO (V) | 40 | 40 | 40 | 40 | 40 | 40 | 40 |
| Continuous Collector Current (mA) | 200 | 200 | 200 | 200 | 200 | 200 | 200 |
| Power Dissipation (mW) | 300 | 300 | 300 | 300 | 330 | 300 | 200 |
| Transition Frequency fT (MHz) | 300 | 300 | 300 | 300 | 300 | 300 | 300 |
| DC Current Gain hFE | 100-300 | 100-300 | 100-300 | 100-300 | 100-300 | 100-300 | 100-300 |
| RoHS / Lead-Free | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
Wichtigste Unterscheidungsmerkmale
- Cross-brand second sourcing with identical footprint and ratings (vs. onsemi MMBT3904LT1G)
- Direct SOT-23 drop-in equivalent of legacy 2N3904 (vs. Through-hole 2N3904 (TO-92))
- Same die across multiple reel and packaging codes (vs. MMBT3904-13-F / MMBT3904LP-7)
Designhinweise
Estimated: At IC=200 mA and VCE=10 V, power dissipation reaches 2 W which far exceeds the 300 mW SOT-23 rating. SOT-23 thermal resistance (theta_JA) is approximately 357 C/W on a standard JEDEC test board, so 300 mW produces a 107 C junction temperature rise above 25 C ambient, well below the 150 C maximum. For continuous operation above 100 mA, derate linearly or move to a DPAK-packaged part such as the MJD200. Avoid operating at the absolute maximum IC=200 mA continuously unless ambient temperature is below 50 C.
Use a minimum copper pour connected to the collector pin and a thermal via array under the SOT-23 thermal pad to reduce theta_JA by 30-40%. Place the base resistor as close as possible to the base pin to minimize parasitic capacitance that can cause oscillation at high frequencies. For switching applications above 100 kHz, add a 100 ohm resistor in series with the base to dampen ringing. A small 10-100 nF bypass capacitor on the collector supply improves switching edges.
Do not confuse the SOT-23 NPN pinout (pin 1 emitter, pin 2 base, pin 3 collector) with the SOT-23 PNP pinout (pin 1 emitter, pin 2 base, pin 3 collector - same NPN-style numbering on MMBT3906). Some competitor parts in SOT-23 may use a different pinout - always check the device-specific datasheet before PCB assembly. Exceeding the 6 V VEBO rating will permanently damage the base-emitter junction, so add a base clamp diode when driving from inductive or higher-voltage sources.
Compliance-Informationen
RoHS, lead-free, halogen-free, antimony-free per Diodes Incorporated datasheet. Not AEC-Q100 qualified; for automotive use, consider AEC-Q100 qualified alternatives from manufacturer automotive lines. REACH compliance per EU regulatory framework.
