AD8571AR

Overview

The AD8571AR is a single-channel, zero-drift operational amplifier manufactured by Analog Devices Inc. It features rail-to-rail input and output capabilities and operates on a single supply voltage ranging from 2.7 V to 5 V. Key electrical specifications include a typical gain bandwidth product of 1.5 MHz, an offset voltage of 1 μV, and an input bias current of 10 pA. The device provides high open-loop gain of 145 dB, a common-mode rejection ratio of 140 dB, and a power supply rejection ratio of 130 dB. It is housed in an 8-lead SOIC package and supports an operating temperature range from -40°C to +125°C.

Feature Summary

• Utilizes a spread-spectrum auto-zero technique to eliminate intermodulation distortion effects in AC applications without requiring external capacitors.
• Features rail-to-rail input and output swings, allowing the input common-mode voltage and output signal to reach both supply rails.
• Combines ultralow offset voltage with minimal drift over the extended industrial temperature range for high DC precision.

Applications

• Temperature sensors
• Pressure sensors
• Precision current sensing
• Strain gage amplifiers
• Medical instrumentation

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and reel specifications. Ensure the selected variant matches the required thermal resistance and pin configuration for the target PCB layout. Cross-reference the datasheet revision history to confirm that all electrical characteristics and absolute maximum ratings align with the intended design requirements before finalizing procurement.

Selection Notes

Select this component for designs requiring high DC accuracy with low noise and no external compensation components. Consider the 1.5 MHz gain bandwidth product and 0.4 V/μs slew rate for signal conditioning tasks. Evaluate the 10 pA input bias current for high-impedance sensor interfaces. Confirm that the single-supply operation fits within the system's available voltage rails and that the SOIC-8 package dimensions are compatible with the assembly process.

Part Context

The AD8571AR belongs to the AD857x family of zero-drift, single-supply, rail-to-rail input/output operational amplifiers. This family includes single (AD8571), dual (AD8572), and quad (AD8574) configurations. All variants share the same core architecture based on Analog Devices' proprietary auto-zero stabilization technology, ensuring consistent performance characteristics across the different channel counts while varying only in physical package and pinout arrangements.

Replacement Considerations

Direct functional substitutes within the same family include the AD8572ARMZ and AD8574ARMZ, provided the application requires multiple channels or different packaging. Verify pin compatibility when substituting between single, dual, and quad versions, as pinouts differ significantly. No other cross-manufacturer replacements are confirmed in the provided source material.

FAQ

Does the AD8571AR require external capacitors for stability?

No, the AD8571/AD8572/AD8574 do not require external capacitors for proper operation or stability due to their internal auto-zero architecture.

What is the mechanism used to achieve low offset drift?

The amplifier uses a random frequency auto-zero stabilization technique that corrects the offset voltage of the main amplifier using a secondary nulling amplifier, eliminating intermodulation distortion.