MMBT3904-7-F - 40V NPN Small Signal BJT 200mA SOT-23 | Diodes Inc
部品番号: MMBT3904-7-F ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 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 概要
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.
ドロップイン代替品: MMBT3904-7-F — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: MMBT3904-7-F （同一形状・フットプリント） — 相違点: DC Current Gain (hFE), Transition Frequency (fT), Collector-Base Voltage (VCBO), Transistor Type, Collector-Emitter Saturation Voltage (VCE(sat)).
クイック比較ツール — 並列比較する代替部品を選択:
MMBT3904-13-F
✅ ドロップイン📋 参考代替品（カタログ未掲載）
MMBT3904LP-7
✅ ドロップイン📋 参考代替品（カタログ未掲載）
MMBT3904LT1G
✅ ドロップイン📋 参考代替品（カタログ未掲載）
SMMBT3904
✅ ドロップイン📋 参考代替品（カタログ未掲載）
MMBT3904LT3G
✅ ドロップイン📋 参考代替品（カタログ未掲載）
MMST3904-7-F
✅ ドロップイン📋 参考代替品（カタログ未掲載）
MMBT3904-7-F 最大定格＆電気的特性
| トランジスタタイプ | NPN Bipolar Junction Transistor (BJT) |
| コレクタ-エミッタ間電圧（Vceo） | 40 V |
| コレクタ-ベース間電圧（Vcbo） | 40 V |
| エミッタ-ベース間電圧（Vebo） | 6 V |
| Continuous Collector Current (IC) | 200 mA |
| Power Dissipation (PD) | 300 mW |
| 遷移周波数（ft） | 300 MHz minimum |
| DC Current Gain (hFE) | 100 to 300 @ IC=10 mA, VCE=1 V |
| コレクタ-エミッタ間飽和電圧（Vce(sat)） | 200 mV typical @ IC=10 mA |
| 動作温度範囲 | -55 C to +150 C |
| パッケージ / ケース | SOT-23-3 |
| 実装タイプ | Surface Mount |
| Die Construction | Epitaxial Planar |
| Complementary PNP Type | MMBT3906-7-F |
| RoHS Compliance | Yes (Lead-Free, Halogen-Free, Antimony-Free) |
MMBT3904-7-F ピン構成
| ピン 1 | Emitter — Emitter terminal (NPN) |
| ピン 2 | Base — Base control terminal |
| ピン 3 | Collector — Collector terminal (NPN) |
主な用途
MMBT3904-7-F の用途: 6 件s: 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.
おすすめ
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.
おすすめ
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.
おすすめ
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.
おすすめ
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.
おすすめ
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.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: MMBT3904-7-F — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | 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 |
主な差別化要因
- 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)
設計ノート
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.
コンプライアンス情報
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.
