SLYS041A March   2020  – March 2021 INA381-Q1

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Wide Input Common-Mode Voltage Range
      2. 7.3.2 Precise Low-Side Current Sensing
      3. 7.3.3 High Bandwidth and Slew Rate
      4. 7.3.4 Alert Output
      5. 7.3.5 Adjustable Overcurrent Threshold
      6. 7.3.6 Comparator Hysteresis
    4. 7.4 Device Functional Modes
      1. 7.4.1 Alert Modes
        1. 7.4.1.1 Transparent Output Mode
        2. 7.4.1.2 Latch Output Mode
  8. Applications and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Select a Current-Sensing Resistor
        1. 8.1.1.1 Select a Current-Sensing Resistor: Example
      2. 8.1.2 Increase Comparator Hysteresis
      3. 8.1.3 Operation With Common-Mode Transients Greater Than 26 V
      4. 8.1.4 Input Filtering
    2. 8.2 Typical Applications
      1. 8.2.1 Bidirectional Window Comparator
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Solenoid Low-Side Current Sensing
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curve
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

Adjustable Overcurrent Threshold

The VOUT voltage is the amplified voltage developed across the current-sensing resistor. The signal developed at the VOUT pin is the input voltage across the IN+ and IN– pins multiplied by the gain of the amplifier. The INA381-Q1 has four gain options, as shown in Figure 7-3: 20 V/V, 50 V/V, 100 V/V, and 200 V/V. If additional hysteresis is not required, directly connect the VOUT pin to the CMPIN pin.

GUID-A4308D77-0F1E-4346-833E-FA47F6E554BB-low.gifFigure 7-3 Resistor Divider Voltage

The device determines if an overcurrent event is present by comparing the voltage on the CMPIN pin to the corresponding signal developed at the CMPREF pin. The threshold voltage for the CMPREF pin can be set with a resistive divider, or by connecting an external voltage source (such as a reference generator device). Figure 7-4 depicts the REF3140 used as an external reference source.

GUID-79D4FB4C-3CE2-48CF-9934-65C138CD08A9-low.gifFigure 7-4 External Reference Voltage