AP1509-50SG-13 from Diodes Incorporated, in a SOP-8. 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	Operating voltage input. Supply pin, recommended 4.5V to 22V (absolute max +24V). Bypass with a bulk input capacitor close to the pin.
2	Output	output	Switching output from the internal 2A power switch. Connects to the external inductor and Schottky catch diode of the buck converter. Saturation voltage ~1.25V typ at IOUT = 2A.
3	FB	input	Output voltage feedback control. On the fixed 5V version this pin is internally tied to sense the 5V output; on adjustable versions the internal reference is VFB = 1.23V. Absolute max -0.3 to +18V.
4	SD	input	ON/OFF shutdown input. Logic low (VIL < 0.6V) enables the regulator; logic high (VIH >= 2.0V) forces standby mode. Absolute max -0.3 to +18V.
5	GND	power_in	Ground return. Pins 5-8 are all GND and should be tied together to the ground plane to improve thermal dissipation of the SOP-8L package.
6	GND	power_in	Ground return. Tie together with pins 5, 7, and 8 to the ground plane.
7	GND	power_in	Ground return. Tie together with pins 5, 6, and 8 to the ground plane.
8	GND	power_in	Ground return. Tie together with pins 5, 6, and 7 to the ground plane.

Key specifications

Parameter	Value
Manufacturer	Diodes Incorporated
Package	SOP-8
Category	PMIC
Pins	8

Ordering variants

Same part, different packaging or reel option.

AP1509-50SG-13

CAD (KiCad official)

Symbol: AP1509-50SG-13
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOP-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`ap1509-50sg-13.step`	122 KB	You want the bare part, or you mark your own boards.
`ap1509-50sg-13-etched.step`	2.9 MB	You want the part with `AP1509-50SG-13` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 690 faces against 147 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: Diodes Incorporated datasheet (12 pp, sha256 736e1f216a8fa351, 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