# BZX55C12PF-M

**ST Semtech** · Zener Diodes · DO-35

BZX55C12PF-M from ST Semtech, in a DO-35. 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 | K | passive | Cathode, the lead on the black cathode band end of the DO-35 glass case, which goes positive in Zener (reverse) operation at VZnom 12 V (11.4 to 12.7 V at 5 mA). |
| 2 | A | passive | Anode, the lead at the end opposite the cathode band of the DO-35 glass case, with a forward voltage of max 1 V at IF = 100 mA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | ST Semtech |
| Package | DO-35 |
| Category | Diodes |
| Pins | 2 |

## CAD (KiCad official)

- Symbol: `BZX55C12PF-M`
- Footprint: `Diode_THT:D_DO-35_SOD27_P7.62mm_Horizontal`
- 3D model: DO-35 (KiCad packages3D, STEP)

## Provenance

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

- **Datasheet:** [ST Semtech datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8602995607946469376) (3 pp, sha256 `ee653f040d509fde`, retrieved 2026-10-13, 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/bzx55c12pf-m-datasheet.pdf)