# L99VR01STR

**STMicroelectronics** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SO-8

L99VR01STR from STMicroelectronics, in a SO-8. 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 | VS | power_in | Supply voltage input (DC absolute maximum -0.3 V to 28 V, with 40 V single-pulse load dump); block directly to ground with a ceramic capacitor of at least 4.7 µF and a 100 nF capacitor placed as close as possible to the pin. |
| 2 | SEL1 | input | Output voltage selector input, with the input voltage limited to -0.3 V to VS + 0.3 V; together with SEL2 and SEL3 it selects the output voltage from 0.8 V to 5 V. |
| 3 | SEL2 | input | Output voltage selector input, with the input voltage limited to -0.3 V to VS + 0.3 V; together with SEL1 and SEL3 it selects the output voltage from 0.8 V to 5 V. |
| 4 | SEL3 | input | Output voltage selector input, with the input voltage limited to -0.3 V to VS + 0.3 V; together with SEL1 and SEL2 it selects the output voltage from 0.8 V to 5 V. |
| 5 | EN | input | Enable input (limited to -0.3 V to VS + 0.3 V): high enables the regulator, watchdog and reset, while low shuts them down and turns on the fast output discharge; connect to VS to keep the device always enabled. |
| 6 | GND | power_in | Ground reference for the device. |
| 7 | RST | output | Reset output, pulled down when the output voltage goes below Vo_th; limited to -0.3 V to VO + 0.3 V and can be left floating if not used. |
| 8 | VO | power_out | Voltage regulator output (200 mA capability); block to ground with a capacitor of at least 3.3 µF for regulator stability. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Package | SO-8 |
| Category | Power Management (PMIC) |
| Pins | 8 |

## CAD (KiCad official)

- Symbol: `L99VR01STR`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SO-8 (KiCad packages3D, STEP)
- 3D model files: `l99vr01str-etched.step` / `l99vr01str-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `l99vr01str.step` / `l99vr01str.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [STMicroelectronics datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590239149862662144) (47 pp, sha256 `4e034c758aa63003`, retrieved 2026-10-08, 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/l99vr01str-datasheet.pdf)