ET3157 from UMW, in a SC-70-6. 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	B1	bidirectional	Analog switch data port B1. Passes through to A when Select is high. Analog signal range 0 to VCC; on-resistance typ 3-17Ω depending on VCC.
2	GND	power_in	Ground / substrate reference (Land).
3	B0	bidirectional	Analog switch data port B0. Passes through to A when Select is low. Analog signal range 0 to VCC.
4	A	bidirectional	Common analog switch port A. Connects to B0 (Select=L) or B1 (Select=H). Bidirectional analog signal path.
5	VCC	power_in	Positive supply, 1.65V to 5.5V operating (absolute max 7V). Sets the analog signal range and logic thresholds.
6	Select	input	Digital channel-select input with over-voltage tolerance up to 7V (may exceed VCC). L = route B0→A, H = route B1→A. Must not be left floating.

Key specifications

Parameter	Value
Manufacturer	UMW
Package	SC-70-6
Category	Interface
Pins	6

CAD (KiCad official)

Symbol: ET3157
Footprint: Package_TO_SOT_SMD:SOT-363_SC-70-6
3D model: SC-70-6 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`et3157.step`	99 KB	You want the bare part, or you mark your own boards.
`et3157-etched.step`	1.2 MB	You want the part with `ET3157` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 301 faces against 117 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: UMW datasheet (13 pp, sha256 3aefe2b48b982b83, 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