# BZW50-39

**STMicroelectronics** · TVS · R6

BZW50-39 from STMicroelectronics, in a R6. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | A | passive | Anode terminal of the unidirectional TVS diode. In the R6 axial package this is one of the two leads; the cathode is identified by the cathode bar marking on the body. |
| 2 | K | passive | Cathode terminal of the unidirectional TVS diode. Identified by the printed cathode bar on the body (unidirectional devices only, per Figure 14 marking layout). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Package | R6 |
| Category | TVS/Fuse/Board Level Protection |
| Pins | 2 |

## Ordering variants

Same part, different packaging or reel option.

- `BZW50-39 (unidirectional)`
- `BZW50-39B (bidirectional)`

## CAD (KiCad official)

- Symbol: `BZW50-39`
- Footprint: `Resistor_THT:R_Array_SIP6`
- 3D model: R6 (KiCad packages3D, STEP)
- 3D model files: `bzw50-39-etched.step` / `bzw50-39-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bzw50-39.step` / `bzw50-39.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [STMicroelectronics datasheet](https://www.st.com/resource/en/datasheet/bzw50-39.pdf) (12 pp, sha256 `e556076e948a7910`, retrieved 2026-08-17, tier: manufacturer)
- **Extractor:** `ds2sf` (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/bzw50-39-datasheet.pdf)