# MMBT3904X

**Shenzhen JingYang** · Bipolar (BJT) · SOT-23

MMBT3904X from Shenzhen JingYang, in a SOT-23. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | BASE | input | Base of the NPN transistor; VEBO (emitter-base voltage, open collector) is limited to 6 V. |
| 2 | EMITTER | passive | Emitter of the NPN transistor; collector current is limited to 200 mA DC. |
| 3 | COLLECTOR | passive | Collector of the NPN transistor; VCEO is 40 V (open base) and VCBO is 60 V (open emitter). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Shenzhen JingYang |
| Package | SOT-23 |
| Category | Transistors/Thyristors |
| Pins | 3 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| collector-base voltage | VCBO |  |  | 60 | V | open emitter | 1 |
| collector-emitter voltage | VCEO |  |  | 40 | V | open base | 1 |
| emitter-base voltage | VEBO |  |  | 6 | V | open collector | 1 |
| collector current (DC) | IC |  |  | 200 | mA |  | 1 |
| total power dissipation | Ptot |  |  | 200 | mW | Tamb≤25°C | 1 |
| storage temperature | Tstg | -55 |  | 150 | °C |  | 1 |
| junction temperature | Tj |  |  | 150 | °C |  | 1 |
| operating ambient temperature | Tamb | -55 |  | 150 | °C |  | 1 |
| collector cut-off current | ICBO |  |  | 0.1 | uA | IE = 0; VCB = 60 V | 2 |
| emitter cut-off current | IEBO |  |  | 0.1 | uA | IC = 0; VEB = 5 V | 2 |
| DC current gain | hFE | 100 |  |  |  | VCE = 1 V; IC = 10mA | 2 |
| DC current gain | hFE | 60 |  | 300 |  | VCE = 1 V; IC = 50mA | 2 |
| DC current gain | hFE | 30 |  |  |  | VCE = 1 V; IC = 100mA | 2 |
| collector-emitter saturation voltage | VCE(sat) |  |  | 200 | mV | IC = 10mA; IB = 1mA | 2 |
| collector-emitter saturation voltage | VCE(sat) |  |  | 300 | mV | IC = 50mA; IB = 5mA | 2 |
| base-emitter saturation voltage | VBE(sat) | 650 |  | 850 | mV | IC = 10mA; IB = 1mA | 2 |
| base-emitter saturation voltage | VBE(sat) |  |  | 950 | mV | IC = 50mA; IB = 5mA | 2 |
| transition frequency | fT | 300 |  |  | MHz | IC =10mA; VCE =20V; f =100MHz | 2 |
| delay time | td |  |  | 35 | ns | VCC=3Vdc, VBE=–0.5Vdc | 2 |
| rise time | tr |  |  | 35 | ns | IC=10mAdc, IB1=1mAdc | 2 |
| storage time | ts |  |  | 200 | ns | VCC=3Vdc, IC=10mAdc | 2 |
| fall time | tf |  |  | 50 | ns | IB1=IB2=1mAdc | 2 |

## CAD (KiCad official)

- Symbol: `MMBT3904X`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `mmbt3904x-etched.step` / `mmbt3904x-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmbt3904x.step` / `mmbt3904x.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [Shenzhen JingYang datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590411692594266112) (5 pp, sha256 `87e2db9915cd262f`, retrieved 2026-10-09, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-5-5` (text+vision), consensus `claude-opus-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/mmbt3904x-datasheet.pdf)