OPA333_17 Datasheet, PDF (12/42 Pages) Texas Instruments – 1.8-V, microPower, CMOS Operational Amplifiers, Zero-Drift Series

OPA333, OPA2333
SBOS351E – MARCH 2006 – REVISED DECEMBER 2015
7 Detailed Description
www.ti.com
7.1 Overview
The OPAx333 is a family of Zero-Drift, low-power, rail-to-rail input and output operational amplifiers. These
devices operate from 1.8 V to 5.5 V, are unity-gain stable, and are suitable for a wide range of general-purpose
applications. The Zero-Drift architecture provides ultra low offset voltage and near-zero offset voltage drift.
7.2 Functional Block Diagram
C2
CHOP1
GM1
CHOP2
Notch
Filter
GM2
+IN
-IN
GM3
OUT
GM_FF
C1
7.3 Feature Description
The OPA333 and OPA2333 are unity-gain stable and free from unexpected output phase reversal. These
devices use a proprietary auto-calibration technique to provide low offset voltage and very low drift over time and
temperature. For lowest offset voltage and precision performance, optimize circuit layout and mechanical
conditions. Avoid temperature gradients that create thermoelectric (Seebeck) effects in the thermocouple
junctions formed from connecting dissimilar conductors. Cancel these thermally-generated potentials by assuring
they are equal on both input terminals. Other layout and design considerations include:
• Use low thermoelectric-coefficient conditions (avoid dissimilar metals).
• Thermally isolate components from power supplies or other heat sources.
• Shield operational amplifier and input circuitry from air currents, such as cooling fans.
Following these guidelines reduces the likelihood of junctions being at different temperatures, which can cause
thermoelectric voltages of 0.1 μV/°C or higher, depending on materials used.
7.3.1 Operating Voltage
The OPA333 and OPA2333 operational amplifiers operate over a power-supply range of 1.8 V to 5.5 V (±0.9 V to
±2.75 V). Parameters that vary over supply voltage or temperature are shown in the Typical Characteristics
section.
CAUTION
Supply voltages higher than +7 V (absolute maximum) can permanently damage the
device.
12
Submit Documentation Feedback
Copyright © 2006–2015, Texas Instruments Incorporated
Product Folder Links: OPA333 OPA2333