# BAS40-04W

**Nexperia** · Schottky Diodes · SOT-323

BAS40-04W from Nexperia, in a SOT-323. 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 | A1 | passive | Anode of diode 1; the device reverse voltage limit is 40 V and the forward current limit is 120 mA. |
| 2 | K2 | passive | Cathode of diode 2; the device reverse voltage limit is 40 V and the forward current limit is 120 mA. |
| 3 | K1, A2 | passive | Cathode of diode 1 and anode of diode 2 are common on this pin, so the two diodes are joined here; the device reverse voltage limit is 40 V and the forward current limit is 120 mA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Nexperia |
| Package | SOT-323 |
| Category | Diodes |
| Pins | 3 |

## CAD (KiCad official)

- Symbol: `BAS40-04W`
- Footprint: `Package_TO_SOT_SMD:SOT-323_SC-70`
- 3D model: SOT-323 (KiCad packages3D, STEP)
- 3D model files: `bas40-04w-etched.step` / `bas40-04w-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `bas40-04w.step` / `bas40-04w.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Nexperia datasheet](https://assets.nexperia.com/documents/data-sheet/BAS40-04W.pdf) (8 pp, sha256 `3920cedf83e79905`, retrieved 2026-10-09, tier: manufacturer)
- **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/bas40-04w-datasheet.pdf)