1 Features

• Precision with zero-crossover distortion:

– Low offset voltage: 50μV (maximum)

– High CMRR: 120dB

– Rail-to-rail I/O

• Wide bandwidth: 40MHz

• Low input bias current: 1pA (maximum)

• Low noise: 6.1nV/√Hz at 10kHz

• Slew rate: 30V/μs

• Fast 0.01% settling time: 180ns

• Single-supply voltage range: 2.2V to 5.5V

• Unity-gain stable

2 Applications

• Optical module

• Position sensor

• Multiparameter patient monitor

• CT and PET scanner

• Chemistry and gas analyzer

• Bidirectional 400-V and 800-V to LV

• Merchant network and server PSU

• String inverter

• Solar power optimizer

3 Description

The single-channel OPA328, dual-channel OPA2328

and quad-channel OPA4328 (OPAx328) are a new

generation family of precision, low-voltage CMOS

operational amplifiers optimized for very low noise

and wide bandwidth.

The OPAx328 have a linear input stage with zerocrossover

distortion that delivers excellent commonmode

rejection ratio (CMRR) of 120dB (typical) over

the full input range. The input common-mode voltage

range extends 100mV beyond the negative and

positive supply rails. The output voltage typically

swings within 10mV of the rails.

The OPAx328 also use Texas Instrument's proprietary

e‑trim™ operational amplifier technology, enabling a

unique combination of ultra-low offset and low input

offset drift without the need for any input switching or

auto-zero techniques.

Low-noise (6.1nV/√Hz) and high-speed operation

(40MHz, 30V/μs) make these devices a great choice

for driving sampling analog-to-digital converters

(ADCs).

The OPAx328 are also a great choice for highimpedance-

input, single-supply applications. Low

input bias current and low input capacitance allows

for high-frequency transimpedance gains at low

photocurrent operation (