# 78L18

**Shikues** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-89-3

78L18 from Shikues, in a SOT-89-3. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | VOUT | power_out | Regulated +18 V output, up to 150 mA. A 0.1 uF ceramic capacitor to GND improves transient response but is not required for stability. |
| 2 | GND | power_in | Common ground reference. Must be shared between input and output. Quiescent current of ~3-5.5 mA flows out of this pin. |
| 3 | VIN | power_in | Unregulated input supply, typically at least VOUT + 2.0 V (dropout), maximum 30 V. Bypass with 0.33 uF close to the pin for stable operation. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Shikues |
| Package | SOT-89-3 |
| Category | 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 tolerance (IO=40mA, VIN=10V), multiple of nominal VOUT | VOUT | 0.964 |  | 1.036 | VOUT | IO=40mA,VIN=10V | 2 |
| Output voltage tolerance (IO=1mA~40mA, VIN=7V~18V), multiple of nominal VOUT | VOUT | 0.96 |  | 1.04 | VOUT | IO=1mA~40mA,VIN=7V~18V | 2 |
| Output voltage tolerance (IO=1mA~10mA, VIN=10V), multiple of nominal VOUT | VOUT | 0.95 |  | 1.05 | VOUT | IO=1mA~10mA,VIN=10V | 2 |
| Output voltage accuracy |  | -5 |  | 5 | % |  | 1 |
| Line regulation | LNR | -150 |  | 150 | mV | VIN=7V~18V,IO=20mA | 2 |
| Line regulation | LNR | -100 |  | 100 | mV | VIN=8V~18V,IO=20mA | 2 |
| Load regulation | LDR | -100 |  | 100 | mV | VIN=10V,IO=1mA~100mA | 2 |
| Load regulation | LDR | -30 |  | 30 | mV | VIN=10V,IO=1mA~40mA | 2 |
| Quiescent current change | ΔIq | -1.5 |  | 1.5 | mA | VIN=8V~18V,IO=20mA | 2 |
| Quiescent current change | ΔIq | -0.1 |  | 0.1 | mA | VIN=10V,IO=1mA~40mA | 2 |
| Dropout voltage | VDIF |  |  | 2 | V | TA=25℃,IO=100mA | 2 |
| Quiescent current | Iq |  |  | 5.5 | mA | VIN=10V,IO=40mA | 2 |
| Output noise voltage | VN |  | 40 |  | uV/VO | F=10Hz~100KHz | 2 |
| Ripple rejection | PSRR |  | 80 |  | dB | TA=25℃,f=120Hz,IO=40mA,VIN=8V~20V | 2 |
| Nominal output voltage (78L18) | VOUT |  | 18 |  | V |  | 1 |
| Input voltage | VIN |  |  | 30 | V |  | 1 |
| Maximum output current | IOUT |  |  | 150 | mA |  | 1 |
| Maximum power dissipation, SOT-89 | Pmax |  |  | 0.5 | W | SOT-89 package | 1 |
| Junction temperature | TJ | -55 |  | 150 | ℃ |  | 2 |
| Operating temperature | Topr | -40 |  | 125 | ℃ |  | 2 |
| Storage temperature range | TSTG | -55 |  | 155 | ℃ |  | 2 |
| Soldering temperature |  |  |  | 260 | ℃ | Recommended 10 s | 2 |
| ESD rating (HBM) |  |  |  | 2 | kV | HBM | 2 |
| Input-output differential (typical) | VIN-VOUT |  | 2 |  | V |  | 4 |

## CAD (KiCad official)

- Symbol: `78L18`
- Footprint: `Package_TO_SOT_SMD:SOT-89-3`
- 3D model: SOT-89-3 (KiCad packages3D, STEP)
- 3D model files: `78l18-etched.step` / `78l18-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `78l18.step` / `78l18.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Shikues datasheet](docs/78l18-datasheet.pdf) (7 pp, sha256 `2f2bf1f5a553c543`, retrieved 2026-08-17, tier: lcsc)
- **Extractor:** `ds2sf` (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/78l18-datasheet.pdf)