GX18B20S from GXCAS, in a TO-92S. 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	Ground reference for the device. Must be tied to system ground; when the device operates in parasite-power mode the VDD pin must also be tied to GND.
2	DQ	bidirectional	1-Wire data input/output. Open-drain bidirectional data line; requires an external ~5 kΩ (typ. shown as 1 kΩ in strong-pullup examples) pull-up to VDD. Also supplies power to the device when used in parasite-power mode (charging the internal CPP capacitor while the bus is high).
3	VDD	power_in	Optional external supply pin, 2.5 V to 5.5 V. Provides local power to the device; must be grounded when operating in parasite-power mode (device is powered from the DQ line instead).

Key specifications

Parameter	Value
Manufacturer	GXCAS
Package	TO-92S
Category	Sensor
Pins	3

Ordering variants

Same part, different packaging or reel option.

GX18B20SS
GX18B20SWS
GX18B20SA

CAD (KiCad official)

Symbol: GX18B20S
Footprint: Package_TO_SOT_THT:TO-92_Inline
3D model: TO-92S (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`gx18b20s.step`	27 KB	You want the bare part, or you mark your own boards.
`gx18b20s-etched.step`	1.7 MB	You want the part with `GX18B20S` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 401 faces against 19 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: GXCAS datasheet (33 pp, sha256 5ccf9b30c1910e5c, retrieved 2026-08-17, tier: lcsc)
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