COS128UA from COSINE, in a SOP-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	RG	passive	Gain setting pin. Connect an external gain resistor RG between pin 1 and pin 8 to set voltage gain G = 1 + 50kΩ/RG (COS128). Leave open (NC) for unity gain.
2	VIN-	input	Inverting (negative) analog input to the instrumentation amplifier. Diode-clamped to the supply rails; input signals exceeding rails by >0.5V should be current-limited to ≤10mA. Bias current ±2nA typ.
3	VIN+	input	Non-inverting (positive) analog input to the instrumentation amplifier. Diode-clamped to supply rails; input signals exceeding rails by >0.5V should be current-limited to ≤10mA. Bias current ±2nA typ.
4	-VS	power_in	Negative power supply pin. Operating range ±2.25V to ±18V (dual supply) or ground for single-supply operation. Bypass to ground with a 0.1µF ceramic capacitor close to the pin.
5	REF	input	Reference input pin. Sets the DC offset of the output; must be driven by a low-impedance source or tied to ground. Series resistance as small as 8Ω degrades CMR to ~80dB.
6	VOUT	output	Amplifier output. Swings to within 1.1V of each supply rail with ±10mA typical load current; short-circuit current ±24mA. Output = G × (VIN+ − VIN−) + VREF.
7	+VS	power_in	Positive power supply pin. Operating range ±2.25V to ±18V dual, or +4.5V to +36V single supply. Bypass with a 0.1µF ceramic capacitor close to the pin; 2.2µF tantalum optional for better performance. Quiescent current 1.0mA typ.
8	RG	passive	Gain setting pin. Connect an external gain resistor RG between pin 1 and pin 8 to set voltage gain G = 1 + 50kΩ/RG (COS128). Leave open (NC) for unity gain.

Key specifications

Parameter	Value
Manufacturer	COSINE
Package	SOP-8
Category	Op-amp/Cmp
Pins	8

Ordering variants

Same part, different packaging or reel option.

COS128UAU
COS128UA
COS128UAC
COS128UAP
COS128UAPA

CAD (KiCad official)

Symbol: COS128UA
Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
3D model: SOP-8 (KiCad packages3D, STEP)

Provenance

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

Datasheet: COSINE datasheet (8 pp, sha256 e35a1a4eec057f26, 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