L78L12ACUTR from STMicroelectronics, in a SOT-89-3. 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	VOUT	power_out	Regulated +12 V output pin. Delivers up to 100 mA into the load with typical output voltage 12 V (min 11.04 V / max 12.96 V for the AC grade at TJ=25 C). A 0.1 uF ceramic capacitor to GND is recommended for stability.
2	GND	power_in	Common/ground reference pin. On the SOT-89 the GND pin is thermally and electrically tied to the large tab/heat spreader on the back side of the package; connect to a copper ground pour for heat dissipation.
3	VIN	power_in	Unregulated positive input voltage. For the 12 V version, typical operating VI range is roughly 14.5 V to 30 V (absolute maximum 35 V for the 12 V option). Bypass with a 0.33 uF capacitor close to the pin.

Key specifications

Parameter	Value
Manufacturer	STMicroelectronics
Package	SOT-89-3
Category	PMIC
Pins	3

Ordering variants

Same part, different packaging or reel option.

L78L12ACUTR
L78L12ACUTRAZ
L78L12ACUTRACZ
L78L12ACUTRABD
L78L12ACUTRACD
L78L12ACUTRD

CAD (KiCad official)

Symbol: L78L12ACUTR
Footprint: Package_TO_SOT_SMD:SOT-89-3
3D model: SOT-89-3 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`l78l12acutr.step`	57 KB	You want the bare part, or you mark your own boards.
`l78l12acutr-etched.step`	1.4 MB	You want the part with `L78L12ACUTR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 370 faces against 42 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: STMicroelectronics datasheet (45 pp, sha256 43922ae159face7e, retrieved 2026-08-17, tier: manufacturer)
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