SBOS378A March   2019  – November 2023 INA185

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 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. 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. 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. Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Precise Low-Side Current Sensing

When used in low-side current sensing applications, the offset voltage of the INA185 is within ±55 µV for A2, A3 and A4 devices. The low offset performance of the INA185 has two main benefits. First, the low offset allows these devices to be used in applications that must measure current over a wide dynamic range. In this case, the low offset improves the accuracy when the sensed currents are on the low end of the measurement range. The other advantage of low offset is the ability to sense lower voltage drop across the sense resistor accurately, thus allowing a lower-value shunt resistor. Lower-value shunt resistors reduce power loss in the current sense circuit, and help improve the power efficiency of the end application.

The gain error of the INA185 is specified to be within 0.2% of the actual value for A1, A2, and A3 devices. As the sensed voltage becomes much larger than the offset voltage, this voltage becomes the dominant source of error in the current sense measurement.