BL1117-CX from BL Shanghai Belling, in a SOT-223-4. 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	GND/ADJ	power_in	Ground (fixed-output versions) or Adjust feedback pin (BL1117-ADJ). On the ADJ variant this pin sets Vout via an external divider following Vout = 1.25 × (1 + R2/R1) + I_ADJ × R2, with I_ADJ typically 55 µA (max 120 µA).
2	Vout	power_out	Regulated output. Delivers up to 1A with 1.3V typical dropout at 1A; recommended output capacitor is 10µF tantalum or MLCC (ESR 3mΩ-22Ω). SOT-223 tab is internally connected to this pin.
3	Vin	power_in	Unregulated input supply. Absolute max 18V (20V for BL1117-12V); recommended input range up to 16V. A 10µF tantalum or MLCC bypass capacitor is recommended close to the pin.

Key specifications

Parameter	Value
Manufacturer	BL Shanghai Belling
Package	SOT-223-4
Category	PMIC
Pins	3

Ordering variants

BL1117-CXX
BL1117-CXY

CAD (KiCad official)

Symbol: BL1117-CX
Footprint: Package_TO_SOT_SMD:SOT-223
3D model: SOT-223-4 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`bl1117-cx.step`	64 KB	You want the bare part, or you mark your own boards.
`bl1117-cx-etched.step`	1.1 MB	You want the part with `BL1117-CX` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 306 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: BL Shanghai Belling datasheet (19 pp, sha256 0a764da9e94a8c7e, 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