# CJ4459A

**Changjing** · MOSFETs · SOT-23

CJ4459A 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 | GATE | input | Gate of the P-channel MOSFET, with maximum gate-source voltage of ±20 V and gate threshold voltage of -1.0 to -2.5 V. |
| 2 | SOURCE | passive | Source of the P-channel MOSFET, with continuous source (body diode) current of -5 A and pulsed -30 A. |
| 3 | DRAIN | passive | Drain of the P-channel MOSFET, rated for drain-source voltage of -30 V and continuous drain current of -5 A (RDS(on) max 46 mΩ at -10 V). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | SOT-23 |
| 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 |
|---|---|---|---|---|---|---|---|
| Drain-Source Breakdown Voltage | V(BR)DSS | -30 |  |  | V | VGS = 0V, ID =-250µA | 2 |
| Zero gate voltage drain current | IDSS |  |  | -1 | µA | VDS =-30V, VGS =0V, TJ=25℃ | 2 |
| Zero gate voltage drain current | IDSS |  |  | -100 | µA | VDS =-30V, VGS =0V, TJ=125℃ | 2 |
| Gate-body leakage current | IGSS | -100 |  | 100 | nA | VDS =0V, VGS =±20V | 2 |
| Gate-threshold voltage | VGS(th) | -2.5 | -1.6 | -1 | V | VDS =VGS, ID =-250µA | 2 |
| Static drain-source on-state resistance | RDS(on) |  | 37 | 46 | mΩ | VGS =-10V, ID =-5A | 2 |
| Static drain-source on-state resistance | RDS(on) |  | 44 | 57 | mΩ | VGS =-4.5V, ID =-5A | 2 |
| Drain-source diode forward voltage | VSD |  |  | -1 | V | VGS =0V, IS=-1A | 2 |
| Continuous drain-source diode forward current | IS |  |  | -5 | A |  | 2 |
| Pulsed drain-source diode forward current | ISM |  |  | -30 | A |  | 2 |
| Drain-Source Voltage | VDS |  |  | -30 | V | TJ=25℃ | 1 |
| Gate-Source Voltage | VGS | -20 |  | 20 | V | TJ=25℃ | 1 |
| Continuous Drain Current | ID |  |  | -5 | A | TJ=25℃ | 1 |
| Pulsed Drain Current | IDM |  |  | -30 | A | TJ=25℃ | 1 |
| Operating Junction and Storage Temperature Range | TJ ,TSTG | -55 |  | 150 | ℃ |  | 1 |
| Thermal Resistance from Junction to Ambient | RθJA |  |  | 62.5 | ℃/W |  | 1 |
| Input capacitance | Ciss |  | 683 |  | pF | VDS =-15V,VGS =0V, f =1MHz | 2 |
| Output capacitance | Coss |  | 97 |  | pF | VDS =-15V,VGS =0V, f =1MHz | 2 |
| Reverse transfer capacitance | Crss |  | 54.6 |  | pF | VDS =-15V,VGS =0V, f =1MHz | 2 |
| Gate resistance | Rg |  | 14 |  | Ω | f =1MHz | 2 |
| Forward transconductance | gFS |  | 6.5 |  | S | VDS =-5V, ID =-5A | 2 |

## CAD (KiCad official)

- Symbol: `CJ4459A`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `cj4459a-etched.step` / `cj4459a-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `cj4459a.step` / `cj4459a.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Changjing datasheet](docs/cj4459a-datasheet.pdf) (7 pp, sha256 `2de229d3cc861b79`, retrieved 2026-10-22, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-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/cj4459a-datasheet.pdf)