XW01K from Sam wing, 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	GND	power_in	Power supply negative / reference ground.
2	C1	passive	Internal balance capacitor pin. Connect a 4.7 nF capacitor to GND (valid range 1-10 nF). Place capacitor close to the chip.
3	CSEL	passive	Sensitivity adjustment capacitor pin. Cap value from 0 pF (unconnected) up to 100 pF; smaller capacitance yields higher sensitivity and smaller gradient threshold.
4	C2	passive	Reference capacitor pin used as the detection comparison baseline. Value should be close to the total parasitic capacitance of the KEY pin (typically 1-10 pF; 5-20 pF when MD=GND).
5	KEY	input	Touch/capacitive sensing input pin. Connect the sensing pad through a series 1 kΩ resistor. Minimum detectable capacitance change (delta_CX) is 0.2 pF.
6	OUT	output	Open-drain key detection output. High-Z (pulled high by external pull-up, e.g. 10 kΩ) when no touch is detected; drives low (Zo ≈ 50 Ω, Isk up to 10 mA @ VDD=5V) when touch/liquid detected.
7	MD	input	Mode select pin. Tie to VDD (or leave floating) for water-level/slow-capacitance detection mode with sleep enabled. Tie to GND for human-body/touch mode with internal auto-learning; no sleep mode when grounded.
8	VDD	power_in	Positive supply, 2.5 V-5.5 V. Typical Idd = 666 µA @ 5.0 V, 394 µA @ 3.0 V; sleep current 55 µA @ 5 V (MD=VDD). Recommend 20 Ω series resistor from supply and 100 nF decoupling to GND close to the pin.

Key specifications

Parameter	Value
Manufacturer	Sam wing
Package	SOP-8
Category	Sensor
Pins	8

CAD (KiCad official)

Symbol: XW01K
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
`xw01k.step`	122 KB	You want the bare part, or you mark your own boards.
`xw01k-etched.step`	1.1 MB	You want the part with `XW01K` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 294 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: Sam wing datasheet (8 pp, sha256 2cce4c0f4a6f252e, retrieved 2026-08-17, tier: lcsc)
Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
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