# KTA1668

**Changjing** · Bipolar Transistors - BJT · SOT-89-3L

KTA1668 from Changjing, in a SOT-89-3L. 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 PNP transistor, rated with an emitter-base breakdown voltage V(BR)EBO of -5 V minimum and a maximum emitter-base voltage VEBO of -5 V. |
| 2 | COLLECTOR | passive | Collector terminal, rated for a collector-emitter voltage VCEO of -60 V, a collector current IC of -1 A and a collector power dissipation PC of 500 mW. |
| 3 | EMITTER | passive | Emitter terminal, rated for an emitter-base voltage VEBO of -5 V and an operating junction and storage temperature range of -55 to 150 ℃. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | SOT-89-3L |
| Category | Triode/MOS Tube/Transistor |
| 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 | -80 |  |  | V | IC=-0.1mA,IE=0 | 1 |
| Collector-emitter breakdown voltage | V(BR)CEO | -60 |  |  | V | IC=-1mA,IB=0 | 1 |
| Emitter-base breakdown voltage | V(BR)EBO | -5 |  |  | V | IE=-0.1mA,IC=0 | 1 |
| Collector cut-off current | ICBO |  |  | -0.1 | μA | VCB=-50V,IE=0 | 1 |
| Emitter cut-off current | IEBO |  |  | -0.1 | μA | VEB=-4V,IC=0 | 1 |
| DC current gain (hFE1) | hFE1 | 60 |  | 320 |  | VCE=-2V,IC=-50mA | 1 |
| DC current gain (hFE2) | hFE2 | 30 |  |  |  | VCE=-2V,IC=-1A | 1 |
| Collector-emitter saturation voltage | VCE(sat) |  |  | -0.7 | V | IC=-500mA,IB=-50mA | 1 |
| Base-emitter saturation voltage | VB E(sat) |  |  | -1.2 | V | IC=-500mA,IB=-50mA | 1 |
| Transition frequency | fT | 150 |  |  | MHz | VCE=-10V,IC=-50mA, f=100MHz | 1 |
| Collector output capacitance | Cob |  |  | 12 | pF | VCB=-10V,IE=0,f=1MHz | 1 |
| Collector-Base Voltage | VCBO | -80 |  |  | V |  | 1 |
| Collector-Emitter Voltage | VCEO | -60 |  |  | V |  | 1 |
| Emitter-Base Voltage | VEBO | -5 |  |  | V |  | 1 |
| Collector Current | IC | -1 |  |  | A |  | 1 |
| Collector power dissipation | PC |  |  | 500 | mW |  | 1 |
| Operation Junction and Storage Temperature Range | TJ,Tstg | -55 |  | 150 | ℃ |  | 1 |

## CAD (KiCad official)

- Symbol: `KTA1668`
- Footprint: `Package_TO_SOT_SMD:SOT-89-3`
- 3D model: SOT-89-3L (KiCad packages3D, STEP)
- 3D model files: `kta1668-etched.step` / `kta1668-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `kta1668.step` / `kta1668.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Changjing datasheet](docs/kta1668-datasheet.pdf) (3 pp, sha256 `b3dc8940e7d5b97e`, retrieved 2026-11-05, 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/kta1668-datasheet.pdf)