# LM3674MFX-1.2

**Texas Instruments** · DC-DC Converters · SOT-23-5

LM3674MFX-1.2 from Texas Instruments, in a SOT-23-5. 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 | VIN | power_in | Power supply input that connects to the input filter capacitor CIN; the recommended input range is 2.7 V to 5.5 V. |
| 2 | GND | power_in | Ground pin; all voltages are specified with respect to this pin. |
| 3 | EN | input | Enable input: the device is in shutdown mode when the voltage is below 0.4 V and enabled above 1 V, and this pin must not be left floating. |
| 4 | FB | input | Feedback analog input that connects to the output filter capacitor COUT for fixed-voltage versions such as the 1.2 V option; the internal resistor dividers are disabled only on the adjustable version, which requires external dividers R1 and R2. |
| 5 | SW | output | Switching node connection to the internal PFET switch and NFET synchronous rectifier. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOT-23-5 |
| Category | Power Management (PMIC) |
| Pins | 5 |

## CAD (KiCad official)

- Symbol: `LM3674MFX-1.2`
- Footprint: `Package_TO_SOT_SMD:SOT-23-5`
- 3D model: SOT-23-5 (KiCad packages3D, STEP)
- 3D model files: `lm3674mfx-1-2-etched.step` / `lm3674mfx-1-2-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm3674mfx-1-2.step` / `lm3674mfx-1-2.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/lm3674) (27 pp, sha256 `6f7dbf11124b325e`, retrieved 2026-10-11, 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/lm3674mfx-1-2-datasheet.pdf)