# CJ78M09

**Changjing** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · TO-252-2(DPAK)

CJ78M09 from Changjing, in a TO-252-2(DPAK). 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 | IN | power_in | Unregulated input to the regulator, with an absolute maximum input voltage of 35 V; a 0.33 µF input capacitor Ci is recommended, placed as close to the regulator as possible. |
| 2 | GND | power_in | Common ground reference for the regulator, to which the input and output capacitors should be returned. |
| 3 | OUT | power_out | Regulated 9 V output (8.55 V to 9.45 V over 11.5 V to 24 V input and 5 mA to 350 mA load), with a 0.1 µF output capacitor Co recommended and a maximum output current of 0.5 A. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | TO-252-2(DPAK) |
| Category | Power Management (PMIC) |
| 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 |
|---|---|---|---|---|---|---|---|
| Output Voltage | VO | 8.73 | 9 | 9.27 | V |  | 1 |
| Output Voltage | VO | 8.55 | 9 | 9.45 | V | 11.5≤Vi≤24V, Io=5mA-350mA | 1 |
| Load Regulation | ΔVo |  | 20 | 180 | mV | Io=5mA-500mA | 1 |
| Load Regulation | ΔVo |  | 10 | 90 | mV | Io=5mA-200mA | 1 |
| Line Regulation | ΔVo |  | 6 | 100 | mV | 11.5V≤Vi≤26V, Io=200mA | 1 |
| Line Regulation | ΔVo |  | 2 | 50 | mV | 12V≤Vi≤26V, Io=200mA | 1 |
| Quiescent Current | Iq |  | 4.6 | 6 | mA |  | 1 |
| Quiescent Current Change | ΔIq |  | 0.8 |  | mA | 11.5V≤Vi≤26V, Io=200mA | 1 |
| Quiescent Current Change | ΔIq |  | 0.5 |  | mA | 5mA≤IO≤350mA | 1 |
| Ripple Rejection | RR | 56 | 80 |  | dB | 13≤Vi≤23V, f=120Hz, Io=300mA | 1 |
| Output Noise Voltage | VN |  | 60 |  | μV | 10Hz≤f≤100KHz | 1 |
| Dropout Voltage | Vd |  | 2 |  | V | Io=350mA | 1 |
| Short Circuit Current | Isc |  | 250 |  | mA | Vi=16V | 1 |
| Peak Current | Ipk |  | 0.5 |  | A |  | 1 |
| Input Voltage | Vi |  |  | 35 | V |  | 1 |
| Thermal Resistance from Junction to Ambient | RθJA |  |  | 80 | ℃/W |  | 1 |
| Operating Junction Temperature Range | TOPR | -40 |  | 125 | ℃ |  | 1 |
| Storage Temperature Range | TSTG | -65 |  | 150 | ℃ |  | 1 |
| Continuous Total Dissipation (features) | PD |  |  | 1.25 | W |  | 1 |
| Maximum Output Current (features) | IOM |  |  | 0.5 | A |  | 1 |

## CAD (KiCad official)

- Symbol: `CJ78M09`
- Footprint: `Package_TO_SOT_SMD:TO-252-2`
- 3D model: TO-252-2(DPAK) (KiCad packages3D, STEP)
- 3D model files: `cj78m09-etched.step` / `cj78m09-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `cj78m09.step` / `cj78m09.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/8586173785137418240) (5 pp, sha256 `78ed41af6e78898c`, 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/cj78m09-datasheet.pdf)