WL2851E33-5 from WILLSEMI Will Semicon, in a SOT-23-5L. 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	VIN	power_in	Voltage input, 4.75V to 40V operating range (45V abs max). Place a 10µF input capacitor as close to this pin as possible.
2	GND	power_in	Ground reference for the regulator.
3	NC	unconnected	Not connected internally. Leave floating or tie as convenient for layout.
4	NC	unconnected	Not connected internally. Leave floating or tie as convenient for layout.
5	VOUT	power_out	Regulated voltage output. Fixed 3.3V (WL2851E33-5) or 5.0V (WL2851E50-5), ±2% accuracy, up to 150mA typical output current with VIN-VOUT=2V. Requires a 10µF output capacitor placed close to the pin.

Key specifications

Parameter	Value
Manufacturer	WILLSEMI Will Semicon
Package	SOT-23-5L
Category	PMIC
Pins	5

Ordering variants

Same part, different packaging or reel option.

WL2851E33-5/TR
WL2851E50-5/TR

CAD (KiCad official)

Symbol: WL2851E33-5
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: SOT-23-5L (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: WILLSEMI Will Semicon datasheet (9 pp, sha256 c7d5aa7f962c8f17, 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