# LM25085ASDX

**Texas Instruments** · DC-DC Controllers · SON-8-EP(3x3)

LM25085ASDX from Texas Instruments, in a SON-8-EP(3x3). 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 | ADJ | input | Current limit threshold adjustment pin; set by external resistor from VIN in conjunction with external sense resistor or PFET RDS(ON). |
| 2 | RT | input | On-time control input; external resistor from VIN sets buck switch on-time and switching frequency; grounding shuts down the controller. |
| 3 | FB | input | Voltage feedback input to regulation and over-voltage comparators with 0.9V regulation level. |
| 4 | GND | power_in | Circuit ground reference for all internal circuitry. |
| 5 | ISEN | input | Current sense input for current limit detection; connect to PFET drain for RDS(ON) sensing or to PFET source and sense resistor for resistive sensing. |
| 6 | PGATE | output | Gate driver output; connect to the external PFET gate. |
| 7 | VCC | power_out | Bias regulator output providing gate driver voltage relative to VIN; requires low ESR capacitor from VIN to VCC located close to pins. |
| 8 | VIN | power_in | Input supply voltage with operating range 4.5V to 42V; requires low ESR bypass capacitor located close to VIN and GND pins. |
| 9 | EP | passive | Exposed pad (from the footprint; not named in the datasheet pin table). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SON-8-EP(3x3) |
| Category | Power Supply Chip |
| Pins | 9 |

## CAD (KiCad official)

- Symbol: `LM25085ASDX`
- Footprint: `Package_SON:WSON-8-1EP_3x3mm_P0.5mm_EP1.6x2.0mm`
- 3D model: SON-8-EP(3x3) (KiCad packages3D, STEP)
- 3D model files: `lm25085asdx-etched.step` / `lm25085asdx-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm25085asdx.step` / `lm25085asdx.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/lm25085a) (36 pp, sha256 `941a26173c0d4ed5`, retrieved 2026-10-07, 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/lm25085asdx-datasheet.pdf)