INA281A1QDBVRQ1

Overview

The INA281A1QDBVRQ1 is an AEC-Q100 qualified, unidirectional current-sense amplifier from Texas Instruments. It features a wide common-mode voltage range of –4 V to +110 V and operates on a single supply from 2.7 V to 20 V. The device provides a fixed gain of 20 V/V with a maximum gain error of ±0.5% and a typical offset voltage of ±55 µV. It offers a bandwidth of 1.3 MHz and a slew rate of 2.5 V/µs, drawing 1.5 mA of quiescent current. Packaged in a space-saving SOT-23 (DBV) format, it supports automotive temperature grades from –40 °C to +125 °C.

Feature Summary

• Supports negative common-mode voltages down to -4 V for precise measurement of recirculating currents in half-bridge applications.
• Provides high-speed response capabilities suitable for fast overcurrent protection detection.

Applications

• Automatic transmission systems
• Automotive HVAC compressor modules
• Valve and motor actuators

Procurement Notes

Verify the specific suffix 'Q1' confirms AEC-Q100 automotive qualification and functional safety capability. Ensure the 'A1' designation matches the required 20 V/V gain option. Confirm the DBV package variant aligns with PCB layout requirements. Validate that the operating environment remains within the specified -40 °C to +125 °C temperature range.

Selection Notes

Select this component when measuring unidirectional current with high common-mode voltages up to 110 V. The 20 V/V gain is optimal for maximizing output dynamic range with larger shunt resistors. Consider the 1.3 MHz bandwidth for applications requiring rapid fault detection. Verify input bias current stability at high common-mode voltages if leakage sensitivity is critical.

Part Context

This part belongs to the INA281-Q1 family of high-precision current-sense amplifiers designed for automotive environments. It utilizes a zero-drift topology to maintain accuracy across wide temperature ranges. The device distinguishes itself through its ability to operate below ground potential while maintaining high CMRR and low noise performance.

Replacement Considerations

INA281B1QDBVRQ1: Offers identical specifications but with a different pinout configuration for the IN+ and IN– pins.

FAQ

Is the INA281A1QDBVRQ1 capable of bidirectional current sensing?

No, the INA281A1QDBVRQ1 is designed for unidirectional operation only, sensing current sourced from a power supply to a load.

What is the minimum differential input voltage required to keep the output in the linear region?

To ensure linear operation, a differential input voltage of at least 20 mV divided by the gain (1 mV for 20 V/V gain) should be applied.