# CJ2045

**Changjing** · Bipolar Transistors - BJT · SOT-23-6L

CJ2045 from Changjing, in a SOT-23-6L. 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 | C1 | passive | Tr1 NPN collector, rated 40V VCBO, 30V VCEO and 1.5A continuous (5A peak). |
| 2 | B1 | passive | Tr1 NPN base, with emitter-base voltage limited to 7V. |
| 3 | C2 | passive | Tr2 PNP collector, rated -40V VCBO, -30V VCEO and -1.5A continuous (-5A peak). |
| 4 | E2 | passive | Tr2 PNP emitter, with emitter-base voltage limited to -7V. |
| 5 | B2 | passive | Tr2 PNP base, with emitter-base voltage limited to -7V. |
| 6 | E1 | passive | Tr1 NPN emitter, with emitter-base voltage limited to 7V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | SOT-23-6L |
| Category | Triode/MOS Tube/Transistor |
| Pins | 6 |

## 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 voltage (NPN Tr1) | VCBO |  |  | 40 | V | Ta=25℃ | 1 |
| Collector-base voltage (PNP Tr2) | VCBO | -40 |  |  | V | Ta=25℃ | 1 |
| Collector-emitter voltage (NPN Tr1) | VCEX |  |  | 40 | V | Ta=25℃ | 1 |
| Collector-emitter voltage (PNP Tr2) | VCEX | -40 |  |  | V | Ta=25℃ | 1 |
| Collector-emitter voltage (NPN Tr1) | VCEO |  |  | 30 | V | Ta=25℃ | 1 |
| Collector-emitter voltage (PNP Tr2) | VCEO | -30 |  |  | V | Ta=25℃ | 1 |
| Emitter-base voltage (NPN Tr1) | VEBO |  |  | 7 | V | Ta=25℃ | 1 |
| Emitter-base voltage (PNP Tr2) | VEBO | -7 |  |  | V | Ta=25℃ | 1 |
| Collector current continuous (NPN Tr1) | IC |  |  | 1.5 | A | Ta=25℃ | 1 |
| Collector current continuous (PNP Tr2) | IC | -1.5 |  |  | A | Ta=25℃ | 1 |
| Collector current peak (NPN Tr1) | ICM |  |  | 5 | A | Ta=25℃ | 1 |
| Collector current peak (PNP Tr2) | ICM | -5 |  |  | A | Ta=25℃ | 1 |
| Collector power dissipation (NPN Tr1) | PC |  |  | 350 | mW | Ta=25℃ | 1 |
| Collector power dissipation (PNP Tr2) | PC |  |  | 350 | mW | Ta=25℃ | 1 |
| Operating junction and storage temperature range | TJ,Tstg | -55 |  | 150 | ℃ |  | 1 |
| Thermal resistance junction to ambient (NPN Tr1) | RθJA |  | 357 |  | ℃/W | Ta=25℃ | 1 |
| Thermal resistance junction to ambient (PNP Tr2) | RθJA |  | 357 |  | ℃/W | Ta=25℃ | 1 |
| Collector-base breakdown voltage (NPN Tr1) | V(BR)CBO | 40 |  |  | V | IC=100μA, IE=0 | 2 |
| Collector-emitter breakdown voltage (NPN Tr1) | V(BR)CEO | 30 |  |  | V | IC=10mA, IB=0; pulse width≤300µs, duty cycle≤2% | 2 |
| Collector-emitter breakdown voltage (NPN Tr1) | V(BR)CEX | 40 |  |  | V | IC=1μA, VBE(off)=-0.5V | 2 |
| Emitter-base breakdown voltage (NPN Tr1) | V(BR)EBO | 7 |  |  | V | IE=100μA, IC=0 | 2 |
| Collector cut-off current (NPN Tr1) | ICBO |  |  | 20 | nA | VCB=32V, IE=0 | 2 |
| Collector cut-off current ICER (NPN Tr1) | ICER |  |  | 20 | nA | VCE=16V, R≤1kΩ | 2 |
| Emitter cut-off current (NPN Tr1) | IEBO |  |  | 20 | nA | VEB=6V, IC=0 | 2 |
| DC current gain (NPN Tr1) | hFE | 180 |  | 500 |  | VCE=2V, IC=100mA; pulse width≤300µs, duty cycle≤2% | 2 |
| Collector-emitter saturation voltage (NPN Tr1) | VCE(sat) |  |  | 0.375 | V |  | 2 |
| Base-emitter saturation voltage (NPN Tr1) | VBE(sat) |  |  | 1.2 | V | IC=750mA, IB=15mA; pulse width≤300µs, duty cycle≤2% | 2 |
| Collector-base breakdown voltage (PNP Tr2) | V(BR)CBO | -40 |  |  | V | IC=-100μA, IE=0 | 2 |
| Collector-emitter breakdown voltage (PNP Tr2) | V(BR)CEO | -30 |  |  | V | IC=-10mA, IB=0; pulse width≤300µs, duty cycle≤2% | 2 |
| Collector-emitter breakdown voltage (PNP Tr2) | V(BR)CEX | -40 |  |  | V | IC=-1μA, VBE(off)=0.5V | 2 |
| Emitter-base breakdown voltage (PNP Tr2) | V(BR)EBO | -7 |  |  | V | IE=-100μA, IC=0 | 2 |
| Collector cut-off current (PNP Tr2) | ICBO |  |  | -20 | nA | VCB=-32V, IE=0 | 2 |
| Collector cut-off current ICER (PNP Tr2) | ICER |  |  | -20 | nA | VCE=-16V, R≤1kΩ | 2 |
| Emitter cut-off current (PNP Tr2) | IEBO |  |  | -20 | nA | VEB=-6V, IC=0 | 2 |
| DC current gain (PNP Tr2) | hFE | 180 |  | 500 |  | VCE=-2V, IC=-100mA; pulse width≤300µs, duty cycle≤2% | 2 |
| Collector-emitter saturation voltage (PNP Tr2) | VCE(sat) |  |  | -0.375 | V |  | 2 |
| Base-emitter saturation voltage (PNP Tr2) | VBE(sat) |  |  | -1.2 | V | IC=-750mA, IB=-15mA; pulse width≤300µs, duty cycle≤2% | 2 |

## CAD (KiCad official)

- Symbol: `CJ2045`
- Footprint: `Package_TO_SOT_SMD:SOT-23-6`
- 3D model: SOT-23-6L (KiCad packages3D, STEP)
- 3D model files: `cj2045-etched.step` / `cj2045-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `cj2045.step` / `cj2045.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Changjing datasheet](docs/cj2045-datasheet.pdf) (6 pp, sha256 `942cf8152e0fbb84`, retrieved 2026-10-21, 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/cj2045-datasheet.pdf)