RS6331KXF from Jiangsu RUNIC Tech, in a SOT-23-5. 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	OUT	output	Amplifier output. Rail-to-rail; typical output current source ~110mA, short-circuit protected (continuous short-to-ground per absolute-max notes; limit current to 140mA).
2	V-	power_in	Negative (lowest) power supply rail. In single-supply operation tie to GND; supports dual-supply operation down to -2.75V. Vs = (V+)-(V-) must be 2.1V to 5.5V (7V absolute max).
3	+IN	input	Non-inverting (positive) amplifier input. Rail-to-rail input; common-mode range extends from (V-)-0.2V to (V+)+0.2V at Vs=5.5V. Input bias current ~1pA typ, 10pA max at 25degC. Diode-clamped to supply rails; limit input current to +/-10mA.
4	-IN	input	Inverting (negative) amplifier input. Rail-to-rail input; common-mode range extends from (V-)-0.2V to (V+)+0.2V at Vs=5.5V. Diode-clamped to supply rails; limit input current to +/-10mA.
5	V+	power_in	Positive (highest) power supply rail. Operating range 2.1V to 5.5V single-supply (or up to +2.75V dual-supply). 7V absolute maximum across V+ to V-. Quiescent current ~85uA typ, 145uA max.

Key specifications

Parameter	Value
Manufacturer	Jiangsu RUNIC Tech
Package	SOT-23-5
Category	Op-amp/Cmp
Pins	5

Ordering variants

Same part, different packaging or reel option.

RS6331KXF

CAD (KiCad official)

Symbol: RS6331KXF
Footprint: Package_TO_SOT_SMD:SOT-23-5
3D model: SOT-23-5 (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Jiangsu RUNIC Tech datasheet (14 pp, sha256 8f7d0e78bb6869b5, 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