# MMBTSC4081W

**CBI** · Bipolar (BJT) · SOT-323

MMBTSC4081W from CBI, 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 | Base | input | Base of the NPN transistor; VEBO max 7 V and IEBO max 0.1 µA at VEB = 7 V. |
| 2 | Emitter | passive | Emitter of the NPN transistor; collector current IC is rated 150 mA maximum. |
| 3 | Collector | passive | Collector of the NPN transistor; VCBO 60 V, VCEO 50 V, IC 150 mA maximum. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | CBI |
| Package | SOT-323 |
| Category | Transistors/Thyristors |
| Pins | 3 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| DC Current Gain, Group Q | hFE | 120 |  | 270 |  | at VCE = 6 V, IC = 1 mA | 1 |
| DC Current Gain, Group R | hFE | 180 |  | 390 |  | at VCE = 6 V, IC = 1 mA | 1 |
| DC Current Gain, Group S | hFE | 270 |  | 560 |  | at VCE = 6 V, IC = 1 mA | 1 |
| Collector Base Cutoff Current | ICBO |  |  | 0.1 | µA | at VCB = 60 V | 1 |
| Emitter Base Cutoff Current | IEBO |  |  | 0.1 | µA | at VEB = 7 V | 1 |
| Collector Base Breakdown Voltage | V(BR)CBO | 60 |  |  | V | at IC = 50 µA | 1 |
| Collector Emitter Breakdown Voltage | V(BR)CEO | 50 |  |  | V | at IC = 1 mA | 1 |
| Emitter Base Breakdown Voltage | V(BR)EBO | 7 |  |  | V | at IE = 50 µA | 1 |
| Collector Emitter Saturation Voltage | VCE(sat) |  |  | 0.4 | V | at IC = 50 mA, IB = 5 mA | 1 |
| Transition Frequency | fT |  | 180 |  | MHz | at VCE = 12 V, -IE = 2 mA, f = 100 MHz | 1 |
| Collector Output Capacitance | Cob |  | 2 | 3.5 | pF | at VCB = 12 V, f = 1 MHz | 1 |
| Collector Base Voltage | VCBO |  |  | 60 | V |  | 1 |
| Collector Emitter Voltage | VCEO |  |  | 50 | V |  | 1 |
| Emitter Base Voltage | VEBO |  |  | 7 | V |  | 1 |
| Collector Current | IC |  |  | 150 | mA |  | 1 |
| Power Dissipation | Ptot |  |  | 200 | mW |  | 1 |
| Junction Temperature | Tj |  |  | 150 | °C |  | 1 |
| Storage Temperature Range | Tstg | -55 |  | 150 | °C |  | 1 |

## CAD (KiCad official)

- Symbol: `MMBTSC4081W`
- Footprint: `Package_TO_SOT_SMD:SOT-323_SC-70`
- 3D model: SOT-323 (KiCad packages3D, STEP)
- 3D model files: `mmbtsc4081w-etched.step` / `mmbtsc4081w-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmbtsc4081w.step` / `mmbtsc4081w.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/8588954829746016256) (3 pp, sha256 `03dc960b9e47bdbc`, retrieved 2026-10-17, 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/mmbtsc4081w-datasheet.pdf)