# MAX809S

**MSKSEMI** · Supervisor and Reset ICs · SOT-23-3

MAX809S from MSKSEMI, in a SOT-23-3. 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 | GND | power_in | Ground reference for the supervisor. Connect to system ground. |
| 2 | RESET | output | Active-low reset output (RESET-bar). Asserted low when VCC falls below the reset threshold (2.93V typ for MAX809S) and held low for ~200ms after VCC returns above threshold. VOL ≤ 0.3V at ISINK=1.2mA; VOH ≥ 0.8·VCC at ISOURCE=500µA. |
| 3 | VCC | power_in | Supply and monitored input voltage. Operating range 1.0V-6.0V (absolute max 6.5V). ICC ≈ 5.5µA at VCC=6V. The device compares VCC against the internal threshold Vth (2.93V typ for the -S variant). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | MSKSEMI |
| Package | SOT-23-3 |
| Category | PMIC |
| Pins | 3 |

## Ordering variants

Same part, different packaging or reel option.

- `MAX809SS`
- `MAX809S`

## CAD (KiCad official)

- Symbol: `MAX809S`
- Footprint: `Package_TO_SOT_SMD:SOT-23-3`
- 3D model: SOT-23-3 (KiCad packages3D, STEP)
- 3D model files: `max809s-etched.step` / `max809s-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `max809s.step` / `max809s.glb` are the bare package body.

## 3D model downloads

Two STEP files. Same geometry, different body top:

| File | Size | Use it when |
|---|---|---|
| [`max809s.step`](max809s.step) | 59 KB | You want the bare part, or you mark your own boards. |
| [`max809s-etched.step`](max809s-etched.step) | 1.6 MB | You want the part with `MAX809S` already on it. |

The marking in the etched file is real recessed geometry cut into the solid, not a
texture or a decal: 373 faces against 69 in the bare model. It
survives export, section views, and rendering in any CAD tool, and it drops straight
into KiCad or Fusion with no extra setup.

## Provenance

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

- **Datasheet:** [MSKSEMI datasheet](docs/max809s-datasheet.pdf) (6 pp, sha256 `7fc0c8bc22e4d962`, retrieved 2026-08-17, tier: lcsc)
- **Extractor:** `ds2sf` (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/max809s-datasheet.pdf)