1 Features

• Precision operational amplifier with integrated

switches for transimpedance applications

• Wide bandwidth: 40 MHz

• Low offset voltage: 60 μV (max)

• Very low offset drift: 1 μV/°C (max)

• Low input bias current: 0.2 pA

• Rail-to-rail input and output

• Zero-crossover input stage

• Low voltage noise: 6.1 nV/√Hz at 10 kHz

• Low current noise: 0.125 pA/√Hz at 10 kHz

• Low leakage switches: 10 pA

• Slew rate: 30 V/μs

• Quiescent current: 3.8 mA per channel

• Current in shutdown mode: 30 μA

• Output impedance in shutdown mode: 100 GΩ

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

• Unity-gain stable

• Small packages:

– 20-lead, 3.5-mm x 3.5-mm VQFN

– 2.0-mm x 2.0-mm DSBGA

2 Applications

• Optical transport inter-dc interconnect

• Optical module

• Optical network terminal unit (ONT)

• Small cell base station

• Digital multimeter (DMM)

• Data acquisition (DAQ)

3 Description

The OPA3S328 is a precision, low-voltage,

CMOS operational amplifier (op amp) with

integrated switches that are optimized for flexible

transimpedance applications. Low input bias current

and low input capacitance allows for high-frequency

transimpedance gains at low photocurrent operation

(< 1 nA). The integrated switches, low offset, and

rail-to-rail output performance of the OPA3S328

enable high accuracy across multiple decades of

current values. Small packages, along with integrated

switches, allow for selectable transimpedance

gains and help reduce size for space-constrained

applications.

The OPA3S328 features zero-crossover input

technology, giving the flexibility for the input commonmode

range to span the full supply range without

offset deviations. The device provides enable-disable

capability to allow for portable, handheld applications

in test and measurement. When disabled, the

OPA3S328 output impedance is typically 100 GΩ,

allowing for wired-OR applications using multiple

transimpedance channels.