INA281A1IDBVR

Overview

The INA281A1IDBVR is a high-precision current sense amplifier manufactured by Texas Instruments. It features a fixed gain of 20 V/V and operates with a supply voltage range from 2.7 V to 20 V. The device supports bidirectional current sensing within a common-mode voltage range of -4 V to 110 V. Key electrical specifications include a gain bandwidth product of 1.3 MHz, a maximum input offset voltage of 100 µV, and an input bias current of 20 µA. It achieves a typical common-mode rejection ratio (CMRR) of 120 dB and has a maximum gain error of 0.5%. The amplifier draws 1.5 mA of operating supply current and is housed in a SOT-23-5 package.

Feature Summary

• Supports bidirectional current sensing with a wide common-mode voltage range extending up to 110 V
• Provides high precision with a low input offset voltage of 100 µV and high common-mode rejection ratio
• Features a fixed internal gain of 20 V/V for simplified circuit design
• Operates on a single low-voltage supply ranging from 2.7 V to 20 V

Applications

• High-side or low-side current monitoring in industrial automation systems
• Battery management systems requiring precise charge and discharge measurement
• Overcurrent protection circuits in power distribution units
• Motor control applications involving DC brushless or brushed motors

Procurement Notes

Verify the complete part number including the suffix 'R' which indicates reel packaging when ordering. Confirm that the specific grade 'A1' matches the required offset voltage and gain error tolerances for your application. Ensure the SOT-23-5 package footprint aligns with your PCB layout constraints. Check for any recent production changes or obsolescence notices from Texas Instruments before finalizing procurement plans.

Selection Notes

Select this component when a fixed gain of 20 V/V is suitable for the expected signal amplitude. The 1.3 MHz bandwidth allows for response to fast transient currents. Consider the 100 µV offset voltage limit if measuring very small differential voltages across low-value shunt resistors. The wide common-mode range accommodates high-side sensing in systems with large voltage swings relative to ground.

Part Context

This device belongs to the INA281 family of current sense amplifiers from Texas Instruments. The family offers various gain options and accuracy grades. The INA281 series is designed for applications requiring high precision and wide common-mode voltage operation. Other variants in the series may offer different gains such as 50 V/V or 100 V/V, or automotive qualification under the AEC-Q100 standard.

FAQ

Is the INA281A1IDBVR capable of high-side current sensing?

Yes, the device supports both high-side and low-side current sensing due to its wide common-mode voltage range of -4 V to 110 V.

What is the fixed internal gain of this amplifier?

The INA281A1IDBVR has a fixed internal gain of 20 V/V.

Does this part support bidirectional current flow?

Yes, the amplifier is designed to handle bidirectional current sensing, allowing it to detect both positive and negative current flows relative to the reference.