SSP7903P33PR from Shanghai Siproin Microelectronics, 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	GND	power_in	Ground / common return for the regulator. Single-point GND recommended per application circuit.
2	VIN	power_in	Input supply voltage. Absolute maximum 40V, minimum 2.2V. Bypass with ~10µF ceramic capacitor to GND. VIN must be ≥ VOUT + dropout (typ 4mV @ 1mA, 1V @ 1A).
3	VOUT	power_out	Regulated 3.3V output (±2% tolerance). Rated up to 1A maximum output current; current limit typ 1.8A; short-circuit current typ 120mA. Requires ~10µF ceramic output capacitor to GND.

Key specifications

Parameter	Value
Manufacturer	Shanghai Siproin Microelectronics
Package	SOT-89-3
Category	PMIC
Pins	3

Ordering variants

Same part, different packaging or reel option.

SSP7903PxxPx
SSP7903P33PR
SSP7903PxxPBx
SSP7903PxxFx
SSP7903PxxFBx
SSP7903PxxJx

CAD (KiCad official)

Symbol: SSP7903P33PR
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
`ssp7903p33pr.step`	57 KB	You want the bare part, or you mark your own boards.
`ssp7903p33pr-etched.step`	2.1 MB	You want the part with `SSP7903P33PR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 521 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: Shanghai Siproin Microelectronics datasheet (11 pp, sha256 d1763cb71baebbea, 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