# LM2840YQMKX

**Texas Instruments** · DC-DC Converters · TSOT-23-6

LM2840YQMKX from Texas Instruments, in a TSOT-23-6. 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 | CB | input | SW FET gate bias voltage; a CBOOT capacitor (0.15 µF or larger recommended) connects between CB and SW, and CB must not exceed SW voltage by more than 7 V. |
| 2 | GND | power_in | Ground connection for the regulator. |
| 3 | FB | input | Feedback input with VOUT = 0.765 V × (1 + R1/R2); feedback resistors should be between 100 Ω and 10 kΩ to avoid input bias errors, and FB voltage is rated -0.3 V to 5 V. |
| 4 | SHDN | input | Logic-level shutdown input: pull to GND to disable and high to enable (2.3 V or higher logic signal), must not float, and should be tied to VIN if unused. |
| 5 | VIN | power_in | Power input voltage pin with a 4.5 V to 42 V normal operating range (absolute maximum 45 V). |
| 6 | SW | output | Power FET output connecting to the inductor, catch diode and CBOOT capacitor; SW is rated up to 42 V in operation (absolute maximum 45 V). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | TSOT-23-6 |
| Category | Power Management (PMIC) |
| Pins | 6 |

## CAD (KiCad official)

- Symbol: `LM2840YQMKX`
- Footprint: `Package_TO_SOT_SMD:TSOT-23-6`
- 3D model: TSOT-23-6 (KiCad packages3D, STEP)
- 3D model files: `lm2840yqmkx-etched.step` / `lm2840yqmkx-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm2840yqmkx.step` / `lm2840yqmkx.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/lm2841-q1) (25 pp, sha256 `9b519afa4d0599ef`, retrieved 2026-10-08, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **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/lm2840yqmkx-datasheet.pdf)