# KTC3875GR

**Changjing** · Digital Transistors · SOT-23

KTC3875GR 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 transistor, driven relative to the emitter; the datasheet gives no separate pin-specific limit, so it is bounded by the maximum ratings (VEBO 5 V, IC 150 mA, Tj/Tstg -55 to +150 ℃). |
| 2 | EMITTER | passive | Emitter terminal of the NPN transistor; the emitter-base voltage is limited to 5 V (VEBO) and the emitter-base breakdown V(BR)EBO is 5 V at IE=100μA. |
| 3 | COLLECTOR | passive | Collector terminal of the NPN transistor; limited to VCBO 60 V, VCEO 50 V, and collector current IC 150 mA, with collector power dissipation PC 150 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 |
|---|---|---|---|---|---|---|---|
| DC current gain (rank GR) | hFE | 200 |  | 400 |  | VCE= 6V, IC= 2mA | 1 |
| Collector-base breakdown voltage | V(BR)CBO | 60 |  |  | V | IC=100μA,IE=0 | 1 |
| Collector-emitter breakdown voltage | V(BR)CEO | 50 |  |  | V | IC= 1mA, IB=0 | 1 |
| Emitter-base breakdown voltage | V(BR)EBO | 5 |  |  | 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= 5V, IC=0 | 1 |
| Collector-emitter saturation voltage | VCE(sat) |  | 0.1 | 0.25 | V | IC=100mA, IB= 10mA | 1 |
| Base-emitter saturation voltage | VBE(sat) |  |  | 1 | V | IC=100mA, IB= 10mA | 1 |
| Transition frequency | fT | 80 |  |  | MHz | VCE=10V, IC= 1mA | 1 |
| Collector output capacitance | Cob |  | 2 | 3.5 | pF | VCB=10V,IE=0,f=1MHZ | 1 |
| Noise figure | NF |  | 1 | 10 | dB | VCE=6V,IC=0.1mA,Rg=10kΩ,f=1KHZ | 1 |
| Collector-Base Voltage | VCBO |  |  | 60 | V | Ta=25℃ unless otherwise noted | 1 |
| Collector-Emitter Voltage | VCEO |  |  | 50 | V | Ta=25℃ unless otherwise noted | 1 |
| Emitter-Base Voltage | VEBO |  |  | 5 | V | Ta=25℃ unless otherwise noted | 1 |
| Collector Current | IC |  |  | 150 | mA | Ta=25℃ unless otherwise noted | 1 |
| Collector Power Dissipation | PC |  |  | 150 | mW | Ta=25℃ unless otherwise noted | 1 |
| Operation Junction and Storage Temperature Range | TJ,Tstg | -55 |  | 150 | ℃ |  | 1 |
| Thermal Resistance From Junction To Ambient | RΘJA |  |  | 833 | ℃/W |  | 1 |

## CAD (KiCad official)

- Symbol: `KTC3875GR`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `ktc3875gr-etched.step` / `ktc3875gr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ktc3875gr.step` / `ktc3875gr.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/8590931051143917568) (4 pp, sha256 `ec58228629e59969`, retrieved 2026-10-19, 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/ktc3875gr-datasheet.pdf)