INA149AID

Overview

The INA149AID is a high-precision, single-channel differential amplifier manufactured by Texas Instruments in an SOIC-8 surface-mount package. It operates on supply voltages ranging from 4 V to 36 V with a maximum quiescent current of 810 µA. The device features a gain bandwidth product and 3dB bandwidth of 500 kHz, a slew rate of 5 V/µs, and a common-mode rejection ratio (CMRR) of 90 dB. Input offset voltage is specified at 350 µV, while the output can source up to 25 mA per channel. It provides a fixed unity gain of 1 V/V with a gain error of 0.005%. Operating temperatures range from -40°C to +125°C.

Feature Summary

• High common-mode voltage capability allowing precise measurement of small differential signals amidst large common-mode potentials up to ±275 V.
• Integrated precision monolithic construction combining a high-performance operational amplifier with integrated thin-film resistor networks for accuracy.
• Robust input protection against transient common-mode voltages and differential overloads up to 500 V.

Applications

• Isolated signal conditioning in industrial process control systems
• Current sensing applications requiring high common-mode rejection
• Medical equipment signal processing

Procurement Notes

Verify the specific suffix 'A' indicates the graded performance variant compared to standard versions. Confirm the 'ID' suffix corresponds to the SOIC-8 tube packaging format. Ensure compatibility with the required operating temperature range of -40°C to +125°C. Check for moisture sensitivity classification requirements during storage and handling. Validate that the 36 V maximum supply voltage aligns with the target circuit design constraints.

Selection Notes

Select this component when high common-mode voltage rejection is critical alongside low power consumption. The fixed unity gain simplifies circuit design for direct differential-to-single-ended conversion. Consider the 500 kHz bandwidth for moderate-speed applications. The SOIC-8 package offers a compact solution for space-constrained designs. Evaluate the 350 µV input offset voltage against system accuracy requirements.

Part Context

The INA149 belongs to Texas Instruments' family of high common-mode voltage differential amplifiers. It serves as a specialized alternative to traditional isolated amplifiers, offering superior bandwidth and lower power usage. The device integrates precision resistors to eliminate external matching components, ensuring consistent performance across manufacturing batches.

Replacement Considerations

INA149EVM: Evaluation module for testing and development purposes.