# SCJT1117B-ADJ

**Changjing** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-223

SCJT1117B-ADJ from Changjing, in a SOT-223. 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 | ADJ/GND | passive | On the SCJT1117B-ADJ this pin is the adjust terminal, which carries the adjust current IAdj (55 to 120 µA per the characteristics table) and sets the output through the external R1/R2 divider, and the datasheet labels it ADJ/GND because the same pinout is used for the fixed versions where it is ground. |
| 2 | OUTPUT | power_out | Regulated output of the 1A low-dropout regulator, which for the ADJ version is set by VOUT = VREF(1 + R2/R1) + IADJ·R2 and is specified for 1.2 V to 12 V adjustable output. |
| 3 | IN | power_in | Unregulated input supply, with a 20 V absolute maximum input voltage and a 15 V recommended maximum operating input voltage per the ratings table, and it needs a 10 µF tantalum input capacitor in the typical application. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Changjing |
| Package | SOT-223 |
| 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 |
|---|---|---|---|---|---|---|---|
| Reference Voltage | VREF | 1.219 | 1.25 | 1.281 | V | IOUT=10mA, VIN=3.23V; 10mA≤IOUT≤1A, 2.75V≤VIN-VOUT≤12V | 3 |
| Adjust Pin Current | IAdj |  | 55 | 120 | μA | VIN=5V, 10mA≤IOUT≤1A | 3 |
| Line Regulation | LNR |  | 0.03 | 0.2 | %/V | IOUT=10mA, 1.5V≤VIN-VOUT≤10.75V | 3 |
| Input Voltage | Vi |  |  | 20 | V |  | 2 |
| Junction Temperature | Tj | -25 |  | 125 | ℃ |  | 2 |
| Storage Temperature | Tstg | -55 |  | 150 | ℃ |  | 2 |
| Lead Temperature (Soldering) | TL |  |  | 260 | ℃ | Soldering, 10s | 2 |
| ESD Voltage (Machine Model) | VESD |  |  | 400 | V | Machine Model | 2 |
| Input Voltage (recommended) | Vi |  |  | 15 | V |  | 2 |
| Operating Junction Temperature (recommended) | Tj | -25 |  | 125 | ℃ |  | 2 |
| Thermal Resistance from Junction to Ambient | RθJA |  | 10 |  | ℃/W | Junction to ambient | 2 |

## CAD (KiCad official)

- Symbol: `SCJT1117B-ADJ`
- Footprint: `Package_TO_SOT_SMD:SOT-223-3_TabPin2`
- 3D model: SOT-223 (KiCad packages3D, STEP)
- 3D model files: `scjt1117b-adj-etched.step` / `scjt1117b-adj-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `scjt1117b-adj.step` / `scjt1117b-adj.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/8588903727051264000) (7 pp, sha256 `fd37c845798118f3`, retrieved 2026-10-18, 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/scjt1117b-adj-datasheet.pdf)