SBOSA29A June   2020  – November 2023 INA281

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Amplifier Input Common-Mode Signal
        1. 6.3.1.1 Input-Signal Bandwidth
        2. 6.3.1.2 Low Input Bias Current
        3. 6.3.1.3 Low VSENSE Operation
        4. 6.3.1.4 Wide Fixed Gain Output
        5. 6.3.1.5 Wide Supply Range
    4. 6.4 Device Functional Modes
      1. 6.4.1 Unidirectional Operation
      2. 6.4.2 High Signal Throughput
  8. Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 RSENSE and Device Gain Selection
      2. 7.1.2 Input Filtering
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Overload Recovery With Negative VSENSE
      3. 7.2.3 Application Curve
  9. Power Supply Recommendations
  10. Layout
    1. 9.1 Layout Guidelines
    2. 9.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Unidirectional Operation

The INA281-Q1 measures the differential voltage developed by current flowing through a resistor that is commonly referred to as a current-sensing resistor or a current-shunt resistor. The INA281-Q1 operates in unidirectional mode only, meaning it only senses current sourced from a power supply to a system load as shown in Figure 6-2.

GUID-8B14E7F4-AD40-4FAD-A9E5-A858FD03A796-low.gifFigure 6-2 Unidirectional Application

The linear range of the output stage is limited to how close the output voltage can approach ground under zero-input conditions. The zero current output voltage of the INA281-Q1 is very small, with a maximum of GND + 20 mV. Make sure to apply a differential input voltage of (20 mV / Gain) or greater to keep the INA281-Q1 output in the linear region of operation.