INA111BU

The INA111BU is a single-supply, unity-gain stable instrumentation amplifier by Texas Instruments. It can measure small differential voltages, AC or DC, over a very wide common-mode voltage range. INA111BU amplifiers have become popular all over the world due to their low power consumption and cost-effectiveness.

Application Field

The INA111BU is often used as an instrumentation amplifier in laboratory and industrial settings. It is typically used to interface analog transducer signals to analog-to-digital converters (ADCs) in a wide variety of applications. Examples include the monitoring of temperatures, pressures, and other physical parameters. Other applications include bridge and pressure sensing amplifiers, thermocouple amplifiers, and general-purpose instrumentation amplification.

Working Principle

INA111BU amplifiers feature a three op-amp configuration with a floating output follower. This design separates the output from the feedback network, providing low output impedance and complete common-mode rejection. The INA111BU also incorporates voltage-feedback architecture, allowing for excellent stability, accurate gain, and low noise.

The input stage is configured as a differential amplifier. The output stage utilizes a floating output follower, which separates the output from the feedback network. This design produces load independence and thus increased accuracy. An on-board precision resistor networks provides up to a gain of 10,000V/V.

The INA111BU requires no external components for basic operation, making it suitable for low-cost, high-performance applications. It is capable of operating from a single supply of 2.7-12V, making it suitable for use in portable, battery powered, and low voltage systems.