# BC556BTF

**onsemi** · Bipolar (BJT) · TO-92-3

BC556BTF from onsemi, in a TO-92-3. 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 | C | passive | Collector of the PNP transistor; rated VCBO -80 V and VCEO -65 V for the BC556 family, with DC collector current IC of -100 mA. |
| 2 | B | input | Base of the PNP transistor; peak base current IBP is rated at -200 mA (pulse). |
| 3 | E | passive | Emitter of the PNP transistor; emitter-base voltage VEBO is rated at -5 V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | onsemi |
| Package | TO-92-3 |
| Category | Transistors/Thyristors |
| Pins | 3 |

## CAD (KiCad official)

- Symbol: `BC556BTF`
- Footprint: `Package_TO_SOT_THT:TO-92_Inline`
- 3D model: TO-92-3 (KiCad packages3D, STEP)
- 3D model files: `bc556btf-etched.step` / `bc556btf-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bc556btf.step` / `bc556btf.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [onsemi datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588930194576969729) (10 pp, sha256 `0f1da75b5e839bc9`, retrieved 2026-10-09, 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/bc556btf-datasheet.pdf)