# CJA9451

**Changjing** · MOSFETs · SOT-89-3L

CJA9451 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 | GATE | input | Gate terminal; the datasheet rates the continuous gate-source voltage at ±12 V and the gate-threshold voltage at −0.50 V to −1.50 V (VDS = VGS, ID = −0.25 mA). |
| 2 | DRAIN | passive | Drain terminal; rated for a drain-source voltage VDS of −20 V and a continuous drain current ID of −2.3 A. |
| 3 | SOURCE | passive | Source terminal, the reference for the rated gate-source voltage of ±12 V; the datasheet gives no separate pin-specific limit for it. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | SOT-89-3L |
| 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 |
|---|---|---|---|---|---|---|---|
| Drain-Source Voltage | VDS |  |  | -20 | V |  | 1 |
| Continuous Gate-Source Voltage | VGS | -12 |  | 12 | V |  | 1 |
| Continuous Drain Current | ID |  |  | -2.3 | A |  | 1 |
| Power Dissipation | PD |  |  | 0.5 | W |  | 1 |
| Operating Temperature | Tj |  |  | 150 | ℃ |  | 1 |
| Storage Temperature | Tstg | -55 |  | 150 | ℃ |  | 1 |
| Thermal Resistance from Junction to Ambient | RθJA |  |  | 250 | ℃/W |  | 1 |
| Drain-source breakdown voltage | V(BR)DSS | -20 |  |  | V | VGS = 0V, ID =10µA | 2 |
| Gate-body leakage | IGSS | -100 |  | 100 | nA | VDS =0V, VGS =±12V | 2 |
| Zero gate voltage drain current | IDSS |  |  | -1 | µA | VDS =-20V, VGS =0V | 2 |
| Gate-threshold voltage | VGS(th) | -0.5 |  | -1.5 | V | VDS =VGS, ID =-0.25mA | 2 |
| Static drain-source on-resistance (note 1) | RDS(on) |  |  | 0.135 | Ω | VGS =-4.5V, ID =-2.3A | 2 |
| Static drain-source on-resistance (note 1) | RDS(on) |  |  | 0.24 | Ω | VGS =-2.5V, ID =-1.0A | 2 |
| Forward transconductance (note 1) | gfs |  | 2.3 |  | S | VDS =-5V, ID =-2.3A | 2 |
| Input capacitance | Ciss |  | 430 |  | pF | VDS =-20V,VGS =0V, f=1MHz | 2 |
| Output capacitance | Coss |  | 100 |  | pF | VDS =-20V,VGS =0V, f=1MHz | 2 |
| Reverse transfer capacitance | Crss |  | 35 |  | pF | VDS =-20V,VGS =0V, f=1MHz | 2 |
| Turn-on delay time (note 1,2) | td(on) |  | 9 |  | ns | VGS=-5V, VDS=-10V, ID =-1A,RG=3.3Ω, RD=10Ω | 2 |
| Rise time (note 2) | tr |  | 25 |  | ns | VGS=-5V, VDS=-10V, ID =-1A,RG=3.3Ω, RD=10Ω | 2 |
| Turn-off delay time (note 2) | td(off) |  | 20 |  | ns | VGS=-5V, VDS=-10V, ID =-1A,RG=3.3Ω, RD=10Ω | 2 |
| Fall time (note 2) | tf |  | 10 |  | ns | VGS=-5V, VDS=-10V, ID =-1A,RG=3.3Ω, RD=10Ω | 2 |
| Body diode forward voltage (note 1) | VSD |  |  | -1.6 | V | IS=-1A, VGS = 0V | 2 |

## CAD (KiCad official)

- Symbol: `CJA9451`
- Footprint: `Package_TO_SOT_SMD:SOT-89-3`
- 3D model: SOT-89-3L (KiCad packages3D, STEP)
- 3D model files: `cja9451-etched.step` / `cja9451-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `cja9451.step` / `cja9451.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/8586174771675873280) (3 pp, sha256 `4f74d6428ac43e17`, 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/cja9451-datasheet.pdf)