# 2N3904-338

**ALJ** · Bipolar (BJT) · TO-92

2N3904-338 from ALJ, in a TO-92. 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 | EMITTER | passive | Emitter terminal of the NPN transistor; the datasheet rates the emitter-base voltage VEBO at 6 V. |
| 2 | BASE | passive | Base terminal of the NPN transistor; the datasheet rates the base current IB at 50 mA. |
| 3 | COLLECTOR | passive | Collector terminal of the NPN transistor; the datasheet rates the collector current IC at 200 mA and the collector-emitter voltage VCEO at 40 V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | ALJ |
| Package | TO-92 |
| 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 breakdown voltage | V(BR)CBO | 60 |  |  | V | IC=10uA, IE=0 | 1 |
| Collector-emitter breakdown voltage | V(BR)CEO | 40 |  |  | V | IC=1mA, IB=0 | 1 |
| Emitter-base breakdown voltage | V(BR)EBO | 6 |  |  | V | IE=10μA, IC=0 | 1 |
| Collector cut-off current | ICBO |  |  | 0.1 | μA | VCB=60V, IE=0 | 1 |
| Emitter cut-off current | ICEO |  |  | 0.1 | μA | VCE=40V, IE=0 | 1 |
| DC current gain | hFE(1) | 40 |  |  |  | VCE=1V, IC=0.1mA | 1 |
| DC current gain | hFE(2) | 70 |  |  |  | VCE=1V, IC=1mA | 1 |
| DC current gain | hFE(3) | 100 |  | 400 |  | VCE=1V, IC=10mA | 1 |
| DC current gain | hFE(4) | 60 |  |  |  | VCE=1V, IC=50mA | 1 |
| DC current gain | hFE(5) | 30 |  |  |  | VCE=1V, IC=100mA | 1 |
| Collector-emitter saturation voltage | VCE(sat) |  |  | 0.2 | V | IC=10mA, IB=1mA | 1 |
| Collector-emitter saturation voltage | VCE(sat) |  |  | 0.3 | V | IC=50mA, IB=5mA | 1 |
| Base-emitter saturation voltage | VBE(sat) |  | 0.65 | 0.85 | V | IC=10mA, IB=1mA | 1 |
| Base-emitter saturation voltage | VBE(sat) |  |  | 0.95 | V | IC=50mA, IB=5mA | 1 |
| Transition frequency | fT | 300 |  |  | MHz | VCE=20V, IC=10mA, f=100MHZ | 1 |
| Delay time | td |  |  | 35 | ns | VCC=3V, VBE=0.5V, IC=10mA, IB1=1mA | 1 |
| Rise time | tr |  |  | 35 | ns |  | 1 |
| Storage time | ts |  |  | 200 | ns | VCC=3V, IC=10mA, IB1=IB2=1mA | 1 |
| Fall time | tf |  |  | 50 | ns |  | 1 |
| Collector-base voltage | VCBO |  |  | 60 | V |  | 1 |
| Collector-emitter voltage | VCEO |  |  | 40 | V |  | 1 |
| Emitter-base voltage | VEBO |  |  | 6 | V |  | 1 |
| Collector current | IC |  |  | 200 | mA |  | 1 |
| Base current | IB |  |  | 50 | mA |  | 1 |
| Collector power dissipation | PC |  |  | 625 | mW | Ta=25 | 1 |
| Collector power dissipation | PC |  |  | 1.5 | W | Tc=25 | 1 |
| Junction temperature | Tj |  |  | 150 |  |  | 1 |
| Storage temperature range | Tstg | -55 |  | 150 |  |  | 1 |

## CAD (KiCad official)

- Symbol: `2N3904-338`
- Footprint: `Package_TO_SOT_THT:TO-92_Inline`
- 3D model: TO-92 (KiCad packages3D, STEP)
- 3D model files: `2n3904-338-etched.step` / `2n3904-338-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `2n3904-338.step` / `2n3904-338.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [ALJ datasheet](docs/2n3904-338-datasheet.pdf) (2 pp, sha256 `11a3bd074c11f1a6`, retrieved 2026-11-05, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-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/2n3904-338-datasheet.pdf)