SCW8916B from SOC Shenzhen SinOne Microelectronics, in a SOP-16. 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	VDD	power_in	Positive power supply input. Operating range 3.0V to 5.5V.
2	C	passive	Reference capacitor pin. Connect the external reference capacitor (typ. 104 / 100nF) used by the capacitive detection front-end.
3	VSS	power_in	Ground reference (0 V) for the device.
4	OUT4	output	Channel 4 water-level level-signal output. Outputs 1 when water is detected on CH4, 0 otherwise (active in one-to-one level output mode).
5	OUT3/RXD	bidirectional	Dual-function pin. In level output mode: OUT3 outputs channel 3 water-level status (1 = water, 0 = no water). In UART output mode: acts as UART RXD input.
6	OUT2/TXD	output	Dual-function pin. In level output mode: OUT2 outputs channel 2 water-level status (1 = water, 0 = no water). In UART output mode: acts as UART TXD output at 9600 baud, refreshed every 100 ms.
7	OUT1	output	Channel 1 water-level level-signal output. Outputs 1 when water is detected on CH1, 0 otherwise. Also used to output calibration status pulses in BCD/test mode.
8	TEST	bidirectional	Test/calibration pin (input first, then output). Used by the host to trigger water-present/water-absent calibration and self-check routines via defined low/high pulse patterns after power-up.
9	SENS	input	Sensitivity selection input. Connect an external resistor to VDD to select one of 8 sensitivity levels (3.3K = highest, 10K, 18K, 27K default, 39K, 51K, 68K, 82K = lowest). Also requires a 100K resistor path to VDD; both resistors must be 1% tolerance.
10	OUTS	input	Channel output communication-mode select. 1 (float / H) selects one-to-one level output on OUT1-OUT4; 0 (tied to GND) selects UART output on TXD with all channel states refreshed every 100 ms.
11	TOPT	input	Test/calibration mode select. 0 = calibrate lower water level only; 1 = calibrate both upper and lower water levels.
12	CH1	input	Water-detect sense channel 1 (lowest water-level channel). Connects to the corresponding copper foil on the water-level sense PCB.
13	CH2	input	Water-detect sense channel 2. Connects to the corresponding sense-foil; tie to VSS (GND) if unused.
14	CH3	input	Water-detect sense channel 3. Connects to the corresponding sense-foil; tie to VSS (GND) if unused.
15	CH4	input	Water-detect sense channel 4 (highest water-level channel). Connects to the corresponding sense-foil; tie to VSS (GND) if unused.
16	Reserve	unconnected	Reserved pin. Leave floating on the PCB (do not connect).

Key specifications

Parameter	Value
Manufacturer	SOC Shenzhen SinOne Microelectronics
Package	SOP-16
Category	Sensor
Pins	16

CAD (KiCad official)

Symbol: SCW8916B
Footprint: Package_SO:SOIC-16_3.9x9.9mm_P1.27mm
3D model: SOP-16 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`scw8916b.step`	217 KB	You want the bare part, or you mark your own boards.
`scw8916b-etched.step`	2.6 MB	You want the part with `SCW8916B` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 619 faces against 267 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: SOC Shenzhen SinOne Microelectronics datasheet (7 pp, sha256 797e42d9aab4632e, 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