A1220LLHLT-T from Allegro MicroSystems LLC, in a SOT-23W. 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	Supply voltage input. Operating range 3.3 V to 24 V. Should be bypassed with a 0.1 uF ceramic capacitor to GND close to the device.
2	VOUT	output	Open-drain Hall switch output. Requires an external pull-up resistor to VCC or another rail. Pulls low when the magnetic field crosses the operate threshold and releases at the release threshold.
3	GND	power_in	Ground reference.

Key specifications

Parameter	Value
Manufacturer	Allegro MicroSystems LLC
Package	SOT-23W
Category	Sensor
Pins	3

Ordering variants

A1220LLHLT-T
A1220LLHLT-TLUA-T

CAD (KiCad official)

Symbol: A1220LLHLT-T
Footprint: Package_TO_SOT_SMD:SOT-23
3D model: SOT-23W (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`a1220llhlt-t.step`	59 KB	You want the bare part, or you mark your own boards.
`a1220llhlt-t-etched.step`	1.4 MB	You want the part with `A1220LLHLT-T` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 369 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: Allegro MicroSystems LLC datasheet (16 pp, sha256 23fb399359de64eb, 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