# KIA7818API-U

**KEC Semicon** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · TO-220F

KIA7818API-U from KEC Semicon, in a TO-220F. 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 | INPUT | power_in | Unregulated input voltage terminal; absolute maximum input voltage is 40 V for KIA7818, and it needs a capacitor to GND. |
| 2 | GND | power_in | Ground terminal, also connected to the package, and the reference for the input and output capacitors. |
| 3 | OUTPUT | power_out | Regulated 18 V output (17.3 to 18.7 V at Tj=25°C, IOUT=100mA) with output current in excess of 1 A and internal short-circuit current limiting. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | KEC Semicon |
| Package | TO-220F |
| 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 | VOUT | 17.3 | 18 | 18.7 | V | Tj=25℃, IOUT=100mA | 11 |
| Output Voltage | VOUT | 17.1 |  | 18.9 | V | 21V≤VIN≤33V, 5.0mA≤IOUT≤1.0A, Po≤15W | 11 |
| Input Regulation | Reg line |  | 13 | 360 | mV | Tj=25℃, 21V≤VIN≤33V | 11 |
| Input Regulation | Reg line |  | 4 | 180 | mV | Tj=25℃, 24V≤VIN≤30V | 11 |
| Load Regulation | Reg load |  | 12 | 360 | mV | Tj=25℃, 5mA≤IOUT≤1.4A | 11 |
| Load Regulation | Reg load |  | 4 | 180 | mV | Tj=25℃, 250mA≤IOUT≤750mA | 11 |
| Quiescent Current | IB |  | 4.5 | 8 | mA | Tj=25℃, IOUT=5mA | 11 |
| Quiescent Current Change | IB |  |  | 1 | mA | 21V≤VIN≤33V | 11 |
| Ripple Rejection Ratio | RR | 52 | 68 |  | dB | f=120Hz, 22V≤VIN≤32V, IOUT=50mA, Tj=25℃ | 11 |
| Input Voltage | VIN |  |  | 40 | V | KIA7818 (Ta=25℃) | 1 |
| Power Dissipation-1 (No Heatsink), API | PD1 |  |  | 2 | W | No heatsink, API (TO-220IS), Ta=25℃ | 1 |
| Power Dissipation-2 (Infinite Heatsink), API | PD2 |  |  | 20.8 | W | Infinite heatsink, API (TO-220IS), Ta=25℃ | 1 |
| Operating Junction Temperature | Tj | -40 |  | 150 | °C |  | 1 |
| Storage Temperature | Tstg | -55 |  | 150 | °C |  | 1 |

## CAD (KiCad official)

- Symbol: `KIA7818API-U`
- Footprint: `Package_TO_SOT_THT:TO-220F-3_Vertical`
- 3D model: TO-220F (KiCad packages3D, STEP)

## Provenance

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

- **Datasheet:** [KEC Semicon datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588897177837424640) (20 pp, sha256 `edd644632a33a22d`, retrieved 2026-11-06, 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/kia7818api-u-datasheet.pdf)