1 Features

• Precision with zero-crossover distortion:

– Low offset voltage: 50 μV (maximum)

– High CMRR: 120 dB

– Rail-to-rail I/O

• Wide bandwidth: 40 MHz

• Low input bias current: 1 pA (maximum)

• Low noise: 6.1 nV/√Hz at 10 kHz

• Slew rate: 30 V/μs

• Fast 0.01 settling time: 180 ns

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

• 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 and dual-channel

OPA2328 (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 120 dB (typical)

over the full input range. The input common-mode

voltage range extends 100 mV beyond the negative

and positive supply rails. The output voltage typically

swings within 10 mV 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 (6.1 nV/√Hz) and high-speed operation

(40 MHz, 30 V/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 (