XL1509-12E1 from XLSEMI, in a SOIC-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	Supply Voltage Input Pin. Operates from 4.5V to 40V DC. Bypass VIN to GND with a suitably large capacitor to eliminate input noise. Absolute maximum -0.3V to 45V.
2	OUTPUT	power_out	Power Switch Output Pin (SW). Switching node that supplies power to the external inductor/Schottky diode of the buck converter. Rated for 2A output current.
3	FEEDBACK	input	Feedback Pin (FB). Through an external resistor divider network, senses and regulates the output voltage. Internal reference threshold voltage is 1.23V. For the -12 fixed version, the internal divider is set so a direct connection to VOUT regulates at 12V.
4	ON/OFF	input	Enable Pin. Drive ON/OFF pin low to turn on the device; drive it high to turn it off. Floating defaults low (device on). TTL-compatible shutdown with hysteresis.
5	GND	power_in	Ground Pin. Care must be taken in layout: this pin should be placed outside of the Schottky diode-to-output-capacitor ground path to prevent switching current spikes from inducing voltage noise into the XL1509.
6	GND	power_in	Ground Pin. Care must be taken in layout: this pin should be placed outside of the Schottky diode-to-output-capacitor ground path to prevent switching current spikes from inducing voltage noise into the XL1509.
7	GND	power_in	Ground Pin. Care must be taken in layout: this pin should be placed outside of the Schottky diode-to-output-capacitor ground path to prevent switching current spikes from inducing voltage noise into the XL1509.
8	GND	power_in	Ground Pin. Care must be taken in layout: this pin should be placed outside of the Schottky diode-to-output-capacitor ground path to prevent switching current spikes from inducing voltage noise into the XL1509.

Key specifications

Parameter	Value
Manufacturer	XLSEMI
Package	SOIC-8
Category	PMIC
Pins	8

Ordering variants

Same part, different packaging or reel option.

XL1509-12E1
XL1509-12E13.3E1
XL1509-12E15.0E1
XL1509-12E1ADJE1

CAD (KiCad official)

Symbol: XL1509-12E1
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOIC-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`xl1509-12e1.step`	122 KB	You want the bare part, or you mark your own boards.
`xl1509-12e1-etched.step`	1.9 MB	You want the part with `XL1509-12E1` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 487 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: XLSEMI datasheet (13 pp, sha256 8b10b01cdcb05276, 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