# LM317EMPX

**Texas Instruments** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-223-4

LM317EMPX from Texas Instruments, in a SOT-223-4. 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 | ADJ | input | Adjustment pin; adjustment current 50-100 μA over operating range controls output voltage via external resistive feedback network. |
| 2 | VOUT | output | Output voltage pin; maximum output current 1.5-3.4 A at (VIN-VOUT) ≤ 15 V. |
| 3 | VIN | power_in | Input voltage pin; (VIN-VOUT) voltage differential must be 3-40 V for regulated operation. |
| 4 | VOUT | output | Output voltage thermal pad; maximum output current 1.5-3.4 A at (VIN-VOUT) ≤ 15 V. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOT-223-4 |
| Category | Power Management (PMIC) |
| Pins | 4 |

## CAD (KiCad official)

- Symbol: `LM317EMPX`
- Footprint: `Package_TO_SOT_SMD:SOT-223`
- 3D model: SOT-223-4 (KiCad packages3D, STEP)
- 3D model files: `lm317empx-etched.step` / `lm317empx-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm317empx.step` / `lm317empx.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/lm317-n) (58 pp, sha256 `5d6f181fd09b90b9`, retrieved 2026-09-23, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.2`, primary `claude-haiku-4-5-20251001` (text), consensus `claude-sonnet-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/lm317empx-datasheet.pdf)