AD8574ARU

Overview

The AD8574ARU is a quad zero-drift operational amplifier from Analog Devices, featuring rail-to-rail input and output capabilities. It operates on a single supply voltage ranging from 2.7 V to 5 V. Key electrical characteristics include a typical offset voltage of 1 μV with a drift of 0.005 μV/°C, an ultralow input bias current of 10 pA, and a gain bandwidth product of 1.5 MHz at 5 V. The device offers high open-loop gain (145 dB typical) and CMRR (140 dB typical). It consumes approximately 750 μA per amplifier and functions within an extended temperature range of −40°C to +125°C.

Feature Summary

• Utilizes spread-spectrum auto-zero technology to eliminate intermodulation distortion without requiring external capacitors.
• Provides rail-to-rail input and output swing for maximum dynamic range in low-voltage single-supply applications.
• Delivers ultra-low offset voltage and drift performance suitable for precision DC measurements.
• Features ultralow input bias current to minimize loading effects on high-impedance signal sources.

Applications

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

Procurement Notes

Verify the specific package suffix against the ordering guide, as the RU suffix denotes a TSSOP package. Confirm that the required channel count matches the quad configuration of this part number. Ensure the application environment stays within the specified 2.7 V to 5 V single-supply range and the −40°C to +125°C operating temperature limits defined in the datasheet specifications.

Selection Notes

Select this component when high DC precision is required alongside AC signal integrity, as the random frequency auto-zero technique prevents intermodulation distortion common in traditional chopper amplifiers. It is ideal for battery-powered systems due to its low supply current and single-supply operation. Consider the quad topology if multiple channels are needed in a compact surface-mount footprint compared to using individual single or dual amplifiers.

Part Context

The AD8574ARU belongs to the AD857x family of zero-drift amplifiers, which includes the single-channel AD8571 and dual-channel AD8572 variants. This family shares the same core CMOS architecture and performance characteristics, differing primarily in the number of integrated amplifiers per package. The AD8574 specifically integrates four independent amplifiers in a 14-lead TSSOP package.

Replacement Considerations

Direct functional substitutes within the same family include the AD8571ARU (single channel) and AD8572ARU (dual channel), provided the channel count requirement can be adjusted. Verify pin compatibility and thermal resistance values when substituting between different package types such as SOIC or MSOP variants within the AD857x series.

FAQ

Does the AD8574 require external capacitors for stabilization?

No, the AD8574 does not require external capacitors for proper operation or stabilization due to its internal spread-spectrum auto-zero design.

How does the AD8574 handle intermodulation distortion?

It uses a randomized auto-zero clock frequency to eliminate intermodulation distortion products that typically result from the interaction of chopping functions with signal frequencies.

What is the input voltage range of the AD8574?

The input voltage range extends from the negative supply rail (GND) to the positive supply rail (VS), enabling true rail-to-rail input capability.