Quad, 5.5-V, 20-MHz, zero-cross low-noise (6 nV/√Hz) RRIO operational amplifier

The OPAx323 family of op amps includes

single (OPA323), dual (OPA2323), and quad-channel (OPA4323), low-voltage (1.7V to 5.5V),

high-bandwidth (20MHz) amplifiers (op amps) with a zero-crossover input stage and a

rail-to-rail output stage. The zero-crossover input stage enables OPAx323 to achieve high

linearity and low distortion for input signals with rail-to-rail swing that are typical in

ADC driver applications. Gain-bandwidth of 20MHz provides a fast settling response for ADC

sampling speeds between 0.5MSPS to 5MSPS depending on the settling performance required. The

OPAx323 is well-optimized for power savings as the device consumes just 1.6mA typical

quiescent current.

The OPAx323 easily supports precision

performance in high gain voltage sensing applications such as the wheatstone bridge, because

of a maximum offset drift of 2µV/°C and thermal noise floor of 5.5nV/rt-Hz with a minimum of

100dB CMRR. This unique combination of higher precision (low offset, drift, noise,

distortion, and CMRR) and higher gain-bandwidth (fast settling and slewing) enables use in

multiple applications such as the motor rotary encoders, microphone audio pre-amplifiers and

ultrasonic transducers.

The OPAx323

achieves a high slew-rate of 33V/µs allowing for fast detection of faults in motor current

sensing applications. Unlike traditional amplifiers, the zero-cross over input stage allows

for identical precision performance for both low and high-side sensing applications, thus

making OPAx323 the best choice for current sensing in a variety of end equipments such as

the solar string inverters, power delivery, grid and EV infrastructure. OPAx323S devices

provide shutdown functionality for additional power savings and help disable the amplifier

when idle. The family features standard and small size as well as leaded and QFN packages

across all the channel variants.