SN74LVC1G66DCKR from Texas Instruments, in a SC-70-5. 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	A	bidirectional	Analog/digital I/O port of the bilateral switch. Bidirectional signal terminal connected to B when the switch is ON (C=H). Signal range 0 to VCC (max 5.5V).
2	B	bidirectional	Analog/digital I/O port of the bilateral switch. Bidirectional signal terminal connected to A when the switch is ON (C=H). Signal range 0 to VCC (max 5.5V).
3	GND	power_in	Ground reference pin. Must be tied to system 0V.
4	C	input	Digital control input that opens/closes the analog switch. C=Low turns the switch OFF (A isolated from B); C=High turns the switch ON. VIH/VIL scale with VCC (e.g. VIH≈0.7×VCC at VCC=3.3V).
5	VCC	power_in	Supply voltage input, 1.65V to 5.5V recommended operating range (absolute max 6V for DCK package). Bypass with a local 0.1µF ceramic capacitor to GND.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SC-70-5
Category	Interface
Pins	5

Ordering variants

Same part, different packaging or reel option.

SN74LVC1G66DCKR
SN74LVC1G66DCKRDCKT
SN74LVC1G66DCKRDBVR
SN74LVC1G66DCKRDBVT
SN74LVC1G66DCKRDRLR
SN74LVC1G66DCKRDRYR
SN74LVC1G66DCKRDSFR
SN74LVC1G66DCKRYZPR

CAD (KiCad official)

Symbol: SN74LVC1G66DCKR
Footprint: Package_TO_SOT_SMD:SOT-353_SC-70-5
3D model: SC-70-5 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`sn74lvc1g66dckr.step`	87 KB	You want the bare part, or you mark your own boards.
`sn74lvc1g66dckr-etched.step`	2.5 MB	You want the part with `SN74LVC1G66DCKR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 622 faces against 102 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: Texas Instruments datasheet (44 pp, sha256 9d81b39ddf549369, 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