# MMBTA05

**Changjing** · Bipolar (BJT) · SOT-23

MMBTA05 from Changjing, in a SOT-23. 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 terminal of the NPN driver transistor; the datasheet gives an emitter-base breakdown voltage of 4 V minimum (V(BR)EBO at IE=100μA) and a base-emitter voltage of 1.2 V max at VCE=1V, IC=100mA. |
| 2 | EMITTER | passive | Emitter terminal of the NPN transistor; the absolute maximum emitter-base voltage VEBO is 4 V and the maximum continuous collector current IC is 0.5 A. |
| 3 | COLLECTOR | passive | Collector terminal of the NPN transistor; the absolute maximum collector-base and collector-emitter voltages are 60 V each, with collector power dissipation PC of 300 mW. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | SOT-23 |
| 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 |
|---|---|---|---|---|---|---|---|
| Collector-base breakdown voltage | V(BR)CBO | 60 |  |  | V | IC= 100μA, IE=0 | 1 |
| Collector-emitter breakdown voltage | V(BR)CEO | 60 |  |  | V | IC= 1mA, IB=0 | 1 |
| Emitter-base breakdown voltage | V(BR)EBO | 4 |  |  | V | IE=100μA, IC=0 | 1 |
| Collector cut-off current | ICBO |  |  | 0.1 | μA | VCB=60V, IE=0 | 1 |
| Emitter cut-off current | IEBO |  |  | 0.1 | μA | VEB=3V, IC=0 | 1 |
| DC current gain | hFE1 | 100 |  | 400 |  | VCE=1V, IC= 10mA | 1 |
| DC current gain | hFE2 | 100 |  |  |  | VCE=1V, IC= 100mA | 1 |
| Collector-emitter saturation voltage | VCE(sat) |  |  | 0.25 | V | IC=100mA, IB=10mA | 1 |
| Base-emitter voltage | VBE |  |  | 1.2 | V | VCE=1V, IC= 100mA | 1 |
| Transition frequency | fT | 100 |  |  | MHz | VCE= 2V, IC=10mA, f=100MHz | 1 |
| Collector-base voltage | VCBO |  |  | 60 | V |  | 1 |
| Collector-emitter voltage | VCEO |  |  | 60 | V |  | 1 |
| Emitter-base voltage | VEBO |  |  | 4 | V |  | 1 |
| Collector current -continuous | IC |  |  | 0.5 | A |  | 1 |
| Collector power dissipation | PC |  |  | 300 | mW |  | 1 |
| Junction temperature | TJ |  |  | 150 | ℃ |  | 1 |
| Storage temperature | Tstg | -55 |  | 150 | ℃ |  | 1 |

## CAD (KiCad official)

- Symbol: `MMBTA05`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `mmbta05-etched.step` / `mmbta05-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mmbta05.step` / `mmbta05.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Changjing datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8586171831698509824) (2 pp, sha256 `4edf6833fcb57bc7`, retrieved 2026-10-09, tier: lcsc)
- **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/mmbta05-datasheet.pdf)