# L4949EDTR-E

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

L4949EDTR-E 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 input voltage ranging from 5V to 28V; must be blocked to GND via external capacitor. |
| 2 | SI | input | Sense input for monitoring input voltage; connect via external voltage divider to VS and GND. |
| 3 | VZ | power_out | Preregulator output voltage stabilized to 5V with maximum output current of 10 µA. |
| 4 | CT | input | Reset pulse delay adjustment pin; connect external capacitor to GND to set delay time. |
| 5 | GND | power_in | Ground reference, common return path. |
| 6 | RES | output | Reset output (open-drain) pulled low when output voltage drops below 4.5V threshold. |
| 7 | SO | output | Sense output (open-drain) pulled low when sense input voltage drops below 1.23V threshold. |
| 8 | VOUT | power_out | Regulated output voltage nominally 5V with ±1% accuracy at 1 mA load; block to GND via external capacitor. |

## Key specifications

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

## CAD (KiCad official)

- Symbol: `L4949EDTR-E`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SO-8 (KiCad packages3D, STEP)
- 3D model files: `l4949edtr-e-etched.step` / `l4949edtr-e-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `l4949edtr-e.step` / `l4949edtr-e.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/8588902666756243456) (19 pp, sha256 `eb565c8e521260c1`, retrieved 2026-10-03, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-4-5-20251001` (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/l4949edtr-e-datasheet.pdf)