# LM3401MMX

**Texas Instruments** · LED Drivers · MSOP-8

LM3401MMX from Texas Instruments, in a MSOP-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 | CS | input | Current sense pin, connected to the PFET drain; the datasheet gives an absolute maximum range of -2.0V to 36V for CS. |
| 2 | DIM | input | Dimming input; when DIM is low the HG drive is off, and it can be driven by a logic-level PWM signal (absolute maximum -0.3V to 36V). |
| 3 | SNS | input | Current feedback pin connected to the LED cathode; a resistor from this pin to ground sets the DC LED current (absolute maximum -0.3V to 8V). |
| 4 | HYS | passive | Hysteresis adjust pin; a resistor from this pin to GND sets the hysteresis window (absolute maximum -0.3V to 4V). |
| 5 | GND | power_in | Ground pin for the controller; the datasheet asks that the SNS, HYS and GND connections use an isolated ground area and be grounded close to this pin. |
| 6 | HG | output | Gate drive output that connects to the PFET gate. |
| 7 | VIN | power_in | Power supply input, operating range 4.5V to 35V with an absolute maximum of 36V. |
| 8 | ILIM | passive | Current limit adjust pin; a resistor from this pin to the PFET source sets the current limit threshold (absolute maximum -0.3V to 36V). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | MSOP-8 |
| Category | Nixie Tube Driver/LED Driver |
| Pins | 8 |

## CAD (KiCad official)

- Symbol: `LM3401MMX`
- Footprint: `Package_SO:MSOP-8_3x3mm_P0.65mm`
- 3D model: MSOP-8 (KiCad packages3D, STEP)
- 3D model files: `lm3401mmx-etched.step` / `lm3401mmx-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm3401mmx.step` / `lm3401mmx.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/lm3401) (26 pp, sha256 `5fa65167b595991e`, 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/lm3401mmx-datasheet.pdf)