NCV4266-2CST50T3G from onsemi, 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	I	power_in	Battery supply input voltage. Operating range VQ+0.5 V (or 4.5 V, whichever is higher) up to 45 V; tolerates +45 V peak transient and -42 V reverse. Bypass close to the pin (typ. 1.0 uF + 100 nF).
2	EN	input	Enable input; a low level disables the IC. VEN(high) typ. 2.0 V (max 2.7 V), VEN(low) 0.8 V min. Withstands -42 V to +45 V. Enable input current ~4 uA at VEN = 5.0 V.
3	Q	power_out	Regulated output; bypass with a capacitor to GND (typ. 3.3 uF, ESR in the stable region per Fig. 3/12). Delivers up to 150 mA at 5.0 V +-2%, with 250 mV typical dropout at 100 mA.
4	GND	power_in	Device ground / return. On SOT-223 (Case 318E) this pin is on the tab; connect to a copper pour for thermal dissipation (RthetaJA ~= 109 degC/W, RpsiJT ~= 10.9 degC/W).

Key specifications

Parameter	Value
Manufacturer	onsemi
Package	SOT-223
Category	PMIC
Pins	4

Ordering variants

Same part, different packaging or reel option.

NCV4266-2CST50T3G
NCV4266-2CST50T3GST33T3G

CAD (KiCad official)

Symbol: NCV4266-2CST50T3G
Footprint: Package_TO_SOT_SMD:SOT-223-3_TabPin2
3D model: SOT-223 (KiCad packages3D, STEP)

Provenance

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

Datasheet: onsemi datasheet (13 pp, sha256 bd97fc4713dd2309, 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