L78L05ACZTR from STMicroelectronics, in a TO-92-2.54mm. 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 +5 V output pin, capable of sourcing up to 100 mA. A 0.1 µF ceramic capacitor to GND is recommended for output stability and transient response.
2	GND	power_in	Common ground reference for the input and output. On SOT-89 this pin is also the thermal tab, so PCB copper area on this pin dominates junction-to-ambient thermal performance (RthJA ≈ 55 °C/W with 6 cm² Cu).
3	VIN	power_in	Unregulated positive input voltage. Absolute maximum 30 V for the 5 V output variant; typical operating range gives >2 V of dropout headroom above VOUT. A 0.33 µF input capacitor to GND is recommended, especially if the regulator is located far from the bulk supply capacitor.

Key specifications

Parameter	Value
Manufacturer	STMicroelectronics
Package	TO-92-2.54mm
Category	PMIC
Pins	3

Ordering variants

Same part, different packaging or reel option.

L78L05ACZTR
L78L05ACZTRZ
L78L05ACZTRAZ
L78L05ACZTRD
L78L05ACZTRD13TR

CAD (KiCad official)

Symbol: L78L05ACZTR
Footprint: Package_TO_SOT_THT:TO-92_Inline
3D model: TO-92-2.54mm (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`l78l05acztr.step`	27 KB	You want the bare part, or you mark your own boards.
`l78l05acztr-etched.step`	1.5 MB	You want the part with `L78L05ACZTR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 394 faces against 19 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