REF3318AIDBZR from Texas Instruments, in a SOT-23. 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	IN	power_in	Input supply voltage. Must be at least VOUT + 200 mV up to 5.5 V (absolute max 7.5 V). Bypass to GND with a low-ESR capacitor per the power-supply recommendations.
2	OUT	output	Reference output voltage (1.8 V nominal for REF3318). Sources or sinks up to ±5 mA (30 mA max). Requires a 0.1 µF to 10 µF load capacitor for stability; short-circuit current limited to ~35 mA typ.
3	GND	power_in	Device ground. Common return for input supply and output reference voltage.

Key specifications

Parameter	Value
Manufacturer	Texas Instruments
Package	SOT-23
Category	PMIC
Pins	3

Ordering variants

Same part, different packaging or reel option.

REF3318AIDBZR
REF3318AIDBZT
REF3318AIDBZRIDCKR
REF3318AIDBZRIDCKT
REF3318AIDBZRIRSER
REF3318AIDBZRIRSET

CAD (KiCad official)

Symbol: REF3318AIDBZR
Footprint: Package_TO_SOT_SMD:SOT-23
3D model: SOT-23 (KiCad packages3D, STEP)

3D model downloads

Two STEP files. Same geometry, different body top:

File	Size	Use it when
`ref3318aidbzr.step`	59 KB	You want the bare part, or you mark your own boards.
`ref3318aidbzr-etched.step`	2.3 MB	You want the part with `REF3318AIDBZR` already on it.

The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 562 faces against 69 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 (37 pp, sha256 4f68e657e0bb2b6e, 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