# L4931CD33-TR

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

L4931CD33-TR 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 | VOUT | power_out | Regulated 3.3 V output, up to 250 mA, requiring a 2.2 µF to 10 µF output capacitor with ESR 0.1 to 10 Ω for stability. |
| 2 | GND | power_in | Ground pin. |
| 3 | GND | power_in | Ground pin. |
| 4 | NC | unconnected | No internal connection. |
| 5 | INHIBIT | input | TTL-compatible shutdown control input; logic low max 0.8 V enables the regulator, logic high min 2 V puts it in OFF mode. |
| 6 | GND | power_in | Ground pin. |
| 7 | GND | power_in | Ground pin. |
| 8 | VIN | power_in | Unregulated input voltage, operating up to 20 V (absolute maximum 20 V). |

## Key specifications

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

## CAD (KiCad official)

- Symbol: `L4931CD33-TR`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SO-8 (KiCad packages3D, STEP)
- 3D model files: `l4931cd33-tr-etched.step` / `l4931cd33-tr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `l4931cd33-tr.step` / `l4931cd33-tr.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/8588902956888969216) (32 pp, sha256 `42bf56a6e95ed577`, retrieved 2026-10-07, 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/l4931cd33-tr-datasheet.pdf)