# MT8551AT

**Magn Tek** · Hall Sensor · SOT-23

MT8551AT from Magn Tek, in a SOT-23. 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 | VCC | power_in | Power supply input. Operating range 3.0V to 24V (absolute max 30V). Reverse-battery protected down to -16V. Recommend 100nF decoupling capacitor to GND. |
| 2 | OUT | output | Open-drain switching output. Pulls Low (VDS(ON) < 0.4V at 20mA) when |B| > |BOP|, high-Z (leakage < 10uA at 24V) when |B| < |BRP|. Requires external pull-up resistor (10kOhm recommended). Short-circuit protection current typ 50mA; rise/fall time typ 1us with 20pF load. |
| 3 | GND | power_in | Ground reference for the device. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Magn Tek |
| Package | SOT-23 |
| Category | Sensor |
| Pins | 3 |

## Ordering variants

Same part, different packaging or reel option.

- `MT8551AT`
- `MT8551ATA`

## CAD (KiCad official)

- Symbol: `MT8551AT`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `mt8551at-etched.step` / `mt8551at-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mt8551at.step` / `mt8551at.glb` are the bare package body.

## 3D model downloads

Two STEP files. Same geometry, different body top:

| File | Size | Use it when |
|---|---|---|
| [`mt8551at.step`](mt8551at.step) | 59 KB | You want the bare part, or you mark your own boards. |
| [`mt8551at-etched.step`](mt8551at-etched.step) | 1.3 MB | You want the part with `MT8551AT` already on it. |

The marking in the etched file is real recessed geometry cut into the solid, not a
texture or a decal: 337 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:** [Magn Tek datasheet](docs/mt8551at-datasheet.pdf) (10 pp, sha256 `38399f8942581dbf`, 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/mt8551at-datasheet.pdf)