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 (< 1 nA).