UA78M33CDCYR from Texas Instruments, in a SOT-223. 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	INPUT	power_in	Unregulated supply input. Recommended operating input voltage 5.3 V to 25 V (absolute maximum 35 V). Bypass to COMMON with a 0.33 µF capacitor located close to the pin.
2	COMMON	power_in	Device ground / common reference. Also serves as the thermal path via the SOT-223 tab (fused to pin 2).
3	OUTPUT	power_out	Regulated 3.3-V output, up to 500 mA. Bypass to COMMON with a 0.1 µF capacitor for stability. Dropout voltage typically 2 V.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SOT-223
Category	PMIC
Pins	3

Ordering variants

Same part, different packaging or reel option.

UA78M33CDCYR
UA78M33CDCYRKC
UA78M33CDCYRKCS
UA78M33CDCYRKTP
UA78M33CDCYRKVU

CAD (KiCad official)

Symbol: UA78M33CDCYR
Footprint: Package_TO_SOT_SMD:SOT-223-3_TabPin2
3D model: SOT-223 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`ua78m33cdcyr.step`	64 KB	You want the bare part, or you mark your own boards.
`ua78m33cdcyr-etched.step`	2.3 MB	You want the part with `UA78M33CDCYR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 558 faces against 75 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: Texas Instruments datasheet (28 pp, sha256 2f9e83a70e81dd54, 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