# MMDT3946DW

**CBI** · Bipolar (BJT) · SOT-363

MMDT3946DW from CBI, in a SOT-363. 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 | E1 | passive | Emitter of the 3904-type NPN transistor (Q1); VEBO 5 V, IC up to 0.2 A continuous. |
| 2 | B1 | passive | Base of the 3904-type NPN transistor (Q1); VEBO 5 V max. |
| 3 | C2 | passive | Collector of the 3906-type PNP transistor (Q2); VCEO -40 V, VCBO -40 V, IC -0.2 A continuous. |
| 4 | E2 | passive | Emitter of the 3906-type PNP transistor (Q2); VEBO -5 V max. |
| 5 | B2 | passive | Base of the 3906-type PNP transistor (Q2). |
| 6 | C1 | passive | Collector of the 3904-type NPN transistor (Q1); VCEO 40 V, VCBO 60 V, IC 0.2 A continuous. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | CBI |
| Package | SOT-363 |
| Category | Transistors/Thyristors |
| Pins | 6 |

## CAD (KiCad official)

- Symbol: `MMDT3946DW`
- Footprint: `Package_TO_SOT_SMD:SOT-363_SC-70-6`
- 3D model: SOT-363 (KiCad packages3D, STEP)
- 3D model files: `mmdt3946dw-etched.step` / `mmdt3946dw-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmdt3946dw.step` / `mmdt3946dw.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [CBI datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588944593307623424) (3 pp, sha256 `d4c1481b0427e494`, retrieved 2026-10-09, 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/mmdt3946dw-datasheet.pdf)