SBOS378A March   2019  – November 2023 INA185

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 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. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagrams
    3. 6.3 Feature Description
      1. 6.3.1 High Bandwidth and Slew Rate
      2. 6.3.2 Bidirectional Current Monitoring
      3. 6.3.3 Wide Input Common-Mode Voltage Range
      4. 6.3.4 Precise Low-Side Current Sensing
      5. 6.3.5 Rail-to-Rail Output Swing
    4. 6.4 Device Functional Modes
      1. 6.4.1 Normal Mode
      2. 6.4.2 Unidirectional Mode
      3. 6.4.3 Bidirectional Mode
      4. 6.4.4 Input Differential Overload
      5. 6.4.5 Shutdown Mode
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Basic Connections
      2. 7.1.2 RSENSE and Device Gain Selection
      3. 7.1.3 Signal Filtering
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
      3. 7.2.3 Application Curve
    3. 7.3 Power Supply Recommendations
      1. 7.3.1 Common-Mode Transients Greater Than 26 V
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

6.3.5 Rail-to-Rail Output Swing

The INA185 allows linear current sensing operation with the output close to the supply rail and GND. The maximum specified output swing to the positive rail is 25 mV, and the maximum specified output swing to GND is only 3.5 mV. To compare the output swing of the INA185 to an equivalent operational amplifier (op amp), the inputs are overdriven to approximate the open-loop condition specified in many operational amplifier data sheets. The current-sense amplifier is a closed-loop system, therefore the output swing to GND can be limited by the offset voltage and amplifier gain during unidirectional operation (VREF = 0 V) when there is zero current flowing through the sense resistor. To define the maximum output voltage under the zero current condition, the INA185 Electrical Characteristics table specifies a maximum output voltage of 6 mV for the A1 device, and 12 mV for all other devices.