AD8655ARZ

Overview

The AD8655ARZ is a single-channel, low noise, precision CMOS operational amplifier manufactured by Analog Devices. It features rail-to-rail input and output capabilities and operates on a supply voltage range of 2.7 V to 5.5 V. The device utilizes DigiTrim technology for high DC accuracy, achieving a maximum offset voltage of 250 µV over the common-mode voltage range. Key electrical specifications include a gain bandwidth product of 28 MHz, a slew rate of 11 V/µs, and an input voltage noise density of 2.7 nV/√Hz at 10 kHz. It is housed in an 8-lead SOIC package and supports an operating temperature range from -40°C to +125°C.

Feature Summary

• Utilizes DigiTrim technology to achieve high DC precision with low offset voltage after packaging.
• Features true rail-to-rail architecture allowing input and output signals to extend to both supply rails.
• Provides industry-leading low noise performance suitable for high-resolution data acquisition systems.
• Includes internal protective circuitry that allows input voltages to exceed the power supply rails.

Applications

• ADC and DAC buffers
• Audio microphone pre-amplifiers and mixing consoles
• Industrial controls and precision filters
• Automotive collision avoidance systems

Procurement Notes

Verify the specific ordering suffix to confirm the package type and reel configuration. The 'R' suffix indicates an 8-lead SOIC package, while 'RM' denotes an MSOP package. Ensure the 'Z' suffix is present to confirm RoHS compliance. Confirm the automotive qualification status if required for your application, as standard commercial models differ from qualified automotive variants.

Selection Notes

Select this component when designing low-voltage, single-supply systems requiring high dynamic range and minimal signal distortion. The rail-to-rail input/output capability makes it ideal for buffering wide dynamic range devices like ADCs. Consider its sub-pA input bias current and low noise profile for sensitive sensor interfaces or high-impedance source applications where leakage currents must be minimized.

Part Context

The AD8655ARZ belongs to the AD8655/AD8656 family of precision amplifiers. While the AD8655 provides a single channel, the AD8656 offers dual channels within the same architectural framework. Both utilize the same DigiTrim process and share identical electrical characteristics, differing primarily in the number of circuits per package. This family represents Analog Devices' approach to combining CMOS speed with precision trimming techniques.

Replacement Considerations

The AD8655ARMZ serves as a direct pin-compatible replacement offering the same electrical specifications but packaged in an 8-lead MSOP format instead of the SOIC.

FAQ

Does the AD8655ARZ exhibit phase reversal?

No, the amplifier does not exhibit phase reversal for common-mode voltages within the power supply range.

How does the device handle input overvoltage?

Internal protective circuitry allows voltages exceeding the supply to be applied at the inputs, though series resistors are recommended to limit input current to less than 5 mA.