AD8222ACPZ-WP

AD8222ACPZ-WP is one of the most versatile and accurate instrumentation amplifiers. It is a single-supply, low-noise instrumentation amplifier with low input offset voltage and low consequent drift over temperature. The AD8222ACPZ-WP is suitable for signals from DC to several hundred kilohertz.

Instrumentation amplifiers are used to amplify signals in measurement systems, where the low noise and high accuracy of such amplifiers are critical. The instrumentation amplifiers serve as building blocks for a variety of precision measurements that capture signals such as physiological and biological signals, audio signals, strain, acceleration, pressure and temperature. Instrumentation amplifiers reduce noise, reject common-mode signals, minimize thermal effects, and reduce offset errors. The proper choice of an instrumentation amplifier—such as the AD8222ACPZ-WP—can make a critical difference in the performance of measurement systems.

AD8222ACPZ-WP Application Field and Working Principle

Application Field

The AD8222ACPZ-WP is suitable for a wide range of applications. It is particularly well suited for instrumentation, hearing aid, ECG, pressure, temperature and strain measurements. The AD8222ACPZ-WP also can be used in audiometric and clinical development systems, electrocardiogram systems, speech, loop amplifier systems, precision power supply controllers and load controllers, impedance measurement systems, AC mA/RMS converter, universal bridges, and sigma delta converter applications.

Working Principle

The AD8222ACPZ-WP is a low noise, low power instrumentation amplifier based on the Gilbert cell topology. The device features a precision, low noise input stage and an output stage designed to work on supplies as low as ±1.8 V while achieving excellent CMRR over a wide frequency range. The input stage has a gain adjust range of +1 V/V to +50 V/V, and the output stage offers a range of +1 V/V to +200 V/V. The amplifier is unity-gain stable, and the gain is controlled by a dual-mode 100 kΩ resistor and 16-bit digital potentiometer.

The architecture of the AD8222ACPZ-WP is a classic and well-known Gilbert Cell topology. The circuit is made up of two differential amplifiers, one in the input stage and one in the output stage. In the input stage, the differential amplifiers act as a high input impedance buffer, providing excellent signal integrity. The low noise front-end and the high CMRR are further enhanced by the instrumentation amplifier\'s built-in offset correction circuit. This offset cancellation circuit, combined with a unity-gain feedback loop, allows for excellent signal-to-noise ratio performance.

The AD8222ACPZ-WP is a versatile instrumentation amplifier that offers a wide range of features, from low noise and low power consumption to a wide frequency response range, user-configurable gain, and digital potentiometer support. It is the ideal choice for a wide range of applications such as pressure, temperature, strain, and ECG measurements.