# MMUN5211DW

**CBI** · Digital Transistors · SOT-363

MMUN5211DW 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 | E2 | passive | Emitter of Q2 (NPN BRT with R1 series base and R2 base-emitter resistors, R1=R2=10 kΩ for MMUN5211DW), ground side of the circuit. |
| 2 | B2 | input | Base of Q2 via the series base resistor R1 (10 kΩ nominal, 7 to 13 kΩ), with 10 kΩ R2 base-emitter resistor. |
| 3 | C1 | passive | Collector of Q1, rated for VCEO 50 Vdc, VCBO 50 Vdc and IC 100 mAdc maximum. |
| 4 | E1 | passive | Emitter of Q1 (NPN BRT with integrated R1 and R2 bias network), ground side of the circuit. |
| 5 | B1 | input | Base of Q1 via the series base resistor R1 (10 kΩ nominal, 7 to 13 kΩ), with 10 kΩ R2 base-emitter resistor. |
| 6 | C2 | passive | Collector of Q2, rated for VCEO 50 Vdc, VCBO 50 Vdc and IC 100 mAdc maximum. |

## Key specifications

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

## CAD (KiCad official)

- Symbol: `MMUN5211DW`
- Footprint: `Package_TO_SOT_SMD:SOT-363_SC-70-6`
- 3D model: SOT-363 (KiCad packages3D, STEP)
- 3D model files: `mmun5211dw-etched.step` / `mmun5211dw-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmun5211dw.step` / `mmun5211dw.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/8590920800252088320) (6 pp, sha256 `e1251fafaae545a6`, 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/mmun5211dw-datasheet.pdf)