AP2127K-1.8TRG1 from Diodes Incorporated, in a SOT-23-5. 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	Regulator power input. Operating range 2.5V to 6V (absolute max 6.5V). Bypass with a 1uF low-ESR ceramic capacitor to GND close to the pin.
2	GND	power_in	Device ground reference. Return for input, output, and shutdown pins.
3	Shutdown	input	Active-low enable/shutdown input. Drive >=1.5V to enable the regulator; drive <=0.5V to place the device in shutdown mode (standby current 0.1uA typ). Internally pulled down through ~3M-ohm; drive explicitly for reliable operation.
4	NC	unconnected	No Connection on fixed-voltage versions (this is the AP2127K-1.8, a 1.8V fixed variant). On adjustable versions the same pin is ADJ, the VOUT feedback input connected to a resistor divider. Leave floating on the 1.8V variant.
5	VOUT	power_out	Regulated 1.8V power output, up to 300mA continuous (400mA typical max). Requires a 1uF low-ESR ceramic capacitor to GND for stability. Auto-discharge MOSFET (RDS(ON) ~60 ohm) discharges output during shutdown.

Key specifications

Parameter	Value
Manufacturer	Diodes Incorporated
Package	SOT-23-5
Category	PMIC
Pins	5

Ordering variants

Same part, different packaging or reel option.

AP2127K-1.8TRG1

CAD (KiCad official)

Symbol: AP2127K-1.8TRG1
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: SOT-23-5 (KiCad packages3D, STEP)

Provenance

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

Datasheet: Diodes Incorporated datasheet (24 pp, sha256 d48c96ac985d348a, 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