CAT24C16WI-GT3 from onsemi, in a SOIC-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	NC	unconnected	No Connect. On CAT24C16 all three device-address inputs (A0/A1/A2) are used internally as address bits a8/a9/a10, so this pin is unused.
2	NC	unconnected	No Connect on CAT24C16; the A1 address-select input is used as an internal address bit for the 16-Kb variant.
3	NC	unconnected	No Connect on CAT24C16; the A2 address-select input is used as an internal address bit for the 16-Kb variant.
4	VSS	power_in	Ground reference (0 V) for the device.
5	SDA	bidirectional	Serial Data I/O for the I2C bus. Open-drain output; requires an external pull-up to VCC. Data is clocked in on the rising edge of SCL and shifted out on the falling edge. Schmitt-trigger input with noise suppression; input capacitance 8 pF max.
6	SCL	input	Serial Clock input for the I2C bus, driven by the master. Supports Standard (100 kHz) and Fast (400 kHz) modes. Schmitt-trigger input with noise suppression.
7	WP	input	Write Protect input. When held HIGH, all write operations to the entire memory array are inhibited; when LOW (or left floating; internally pulled LOW), writes are allowed. WP input current 130 uA max at VCC = 5.5 V.
8	VCC	power_in	Supply voltage, 1.7 V to 5.5 V. Read current 1 mA typ, write current 2 mA typ at 400 kHz; standby current 1 uA max (industrial, VCC <= 3.3 V).

Key specifications

Parameter	Value
Manufacturer	onsemi
Package	SOIC-8
Category	Memory
Pins	8

Ordering variants

Same part, different packaging or reel option.

CAT24C16WI-GT3
CAT24C16WI-GT3LI
CAT24C16WI-GT3YI
CAT24C16WI-GT3ZI
CAT24C16WI-GT3USI
CAT24C16WI-GT3VP2I
CAT24C16WI-GT3HU4I
CAT24C16WI-GT3TDI
CAT24C16WI-GT3C5AI
CAT24C16WI-GT3C4AI
CAT24C16WI-GT3C4UI

CAD (KiCad official)

Symbol: CAT24C16WI-GT3
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOIC-8 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`cat24c16wi-gt3.step`	122 KB	You want the bare part, or you mark your own boards.
`cat24c16wi-gt3-etched.step`	2.4 MB	You want the part with `CAT24C16WI-GT3` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 604 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: onsemi datasheet (23 pp, sha256 1068a4f09584c5b3, 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