INA281B5QDBVRQ1

Overview

The INA281B5QDBVRQ1 is an automotive-grade, unidirectional current-sense amplifier featuring a fixed gain of 500 V/V. It operates with a common-mode voltage range from –4 V to +110 V and supports supply voltages between 2.7 V and 20 V. The device offers a bandwidth of 900 kHz, a slew rate of 2.5 V/µs, and a quiescent current of 1.5 mA. Key electrical characteristics include a maximum gain error of ±0.5%, a typical offset voltage of ±15 µV, and a DC CMRR of 120 dB. It is housed in a space-saving SOT-23 package.

Feature Summary

• High-precision zero-drift topology enabling accurate measurement of low differential input voltages across wide temperature ranges.
• Wide common-mode voltage capability allowing operation below ground for recirculating current sensing in half-bridge applications.
• Functional safety capable design with documentation available to aid system integration.
• High-speed response suitable for fast overcurrent protection and rapid detection of inrush currents.

Applications

• Automatic transmission systems
• Automotive HVAC compressor modules
• Valve and motor actuators
• Gasoline and diesel engine platforms
• Pump control circuits

Procurement Notes

Verify the specific suffix 'B5' confirms the 500 V/V gain option and DBVR package variant. Ensure the 'Q1' designation matches AEC-Q100 Grade 1 requirements for your target operating temperature range. Confirm that the unidirectional architecture aligns with your system's current flow direction, as bidirectional variants are not supported by this part number.

Selection Notes

Select this component when high gain is required to amplify small shunt voltages for precise low-current measurements. The 500 V/V gain reduces the necessary sense resistor value, lowering power dissipation. Verify that the 900 kHz bandwidth meets the frequency requirements of your application, as higher gains result in reduced bandwidth compared to lower gain options within the same family.

Part Context

This device belongs to the INA281-Q1 family of high-precision current-sense amplifiers designed for automotive environments. It shares the same core architecture and pinout with other gain variants (20 V/V to 200 V/V), differing primarily in internal resistor networks. The B-series indicates a specific gain configuration within the standardized SOT-23-5 footprint used across the series.

Replacement Considerations

Direct substitutes include other INA281-Q1 variants with different gain settings if system scaling allows. For non-TI replacements, verify equivalent common-mode range, gain accuracy, and automotive qualification status.