# BC549C

**LGE** · Bipolar (BJT) · TO-92

BC549C from LGE, 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 | COLLECTOR | passive | Collector of the NPN transistor; continuous collector current is rated at 100 mAdc with collector-emitter voltage VCEO of 30 V (BC549) or 45 V (BC550). |
| 2 | BASE | input | Base of the NPN transistor; base-emitter on voltage is specified at 0.55 to 0.7 Vdc at IC = 2.0 mAdc and VCE = 5.0 Vdc. |
| 3 | EMITTER | passive | Emitter of the NPN transistor; emitter-base breakdown voltage is 5.0 Vdc minimum (IE = 10 µAdc, IC = 0), and the emitter-base voltage rating VEBO is 5.0 Vdc. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | LGE |
| 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-Emitter Voltage | VCEO |  |  | 30 | Vdc |  | 1 |
| Collector-Base Voltage | VCBO |  |  | 30 | Vdc |  | 1 |
| Emitter-Base Voltage | VEBO |  |  | 5 | Vdc |  | 1 |
| Collector Current, Continuous | IC |  |  | 100 | mAdc |  | 1 |
| Total Device Dissipation | PD |  |  | 625 | mW | TA = 25°C | 1 |
| Total Device Dissipation | PD |  |  | 1.5 | Watt | TC = 25°C | 1 |
| Operating and Storage Junction Temperature Range | TJ, Tstg | -55 |  | 150 | °C |  | 1 |
| Thermal Resistance, Junction to Ambient | RJA |  |  | 200 | °C/W |  | 1 |
| Thermal Resistance, Junction to Case | RJC |  |  | 83.3 | °C/W |  | 1 |
| Collector-Emitter Breakdown Voltage | V(BR)CEO | 30 |  |  | Vdc | IC = 10 mAdc, IB = 0 | 1 |
| Collector-Base Breakdown Voltage | V(BR)CBO | 30 |  |  | Vdc | IC = 10 µAdc, IE = 0 | 1 |
| Emitter-Base Breakdown Voltage | V(BR)EBO | 5 |  |  | Vdc | IE = 10 Adc, IC = 0 | 1 |
| Collector Cutoff Current | ICBO |  |  | 15 | nAdc | VCB = 30 V, IE = 0 | 1 |
| Collector Cutoff Current | ICBO |  |  | 5 | µAdc | VCB = 30 V, IE = 0, TA = +125°C | 1 |
| Emitter Cutoff Current | IEBO |  |  | 15 | nAdc | VEB = 4.0 Vdc, IC = 0 | 1 |
| DC Current Gain | hFE | 420 |  | 800 |  | IC = 2.0 mAdc, VCE = 5.0 Vdc | 2 |
| DC Current Gain | hFE | 100 | 270 |  |  | IC = 10 µAdc, VCE = 5.0 Vdc | 2 |
| Small-Signal Current Gain | hfe | 450 | 600 | 900 |  | IC = 2.0 mAdc, VCE = 5.0 V, f = 1.0 kHz | 2 |
| Noise Figure | NF1 |  |  | 2.5 | dB | IC = 200 µAdc, VCE = 5.0 Vdc, RS = 2.0 kΩ, f = 1.0 kHz | 2 |
| Noise Figure | NF2 |  |  | 10 | dB | IC = 200 µAdc, VCE = 5.0 Vdc, RS = 100 kΩ, f = 1.0 kHz | 2 |

## CAD (KiCad official)

- Symbol: `BC549C`
- Footprint: `Package_TO_SOT_THT:TO-92_Inline`
- 3D model: TO-92 (KiCad packages3D, STEP)
- 3D model files: `bc549c-etched.step` / `bc549c-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bc549c.step` / `bc549c.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [LGE datasheet](docs/bc549c-datasheet.pdf) (4 pp, sha256 `591957e8d3668dbe`, retrieved 2026-10-28, 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/bc549c-datasheet.pdf)