SBOSA30D March   2022  – December 2024

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 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
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Amplifier Input Common-Mode Signal
        1. 7.3.1.1 Enhanced PWM Rejection Operation
        2. 7.3.1.2 Input-Signal Bandwidth
        3. 7.3.1.3 Low Input Bias Current
        4. 7.3.1.4 Low VSENSE Operation
        5. 7.3.1.5 Wide Fixed Gain Output
        6. 7.3.1.6 Wide Supply Range
    4. 7.4 Device Functional Modes
      1. 7.4.1 Adjusting the Output With the Reference Pins
      2. 7.4.2 Reference Pin Connections for Unidirectional Current Measurements
        1. 7.4.2.1 Ground Referenced Output
        2. 7.4.2.2 VS Referenced Output
      3. 7.4.3 Reference Pin Connections for Bidirectional Current Measurements
        1. 7.4.3.1 Output Set to External Reference Voltage
        2. 7.4.3.2 Output Set to Mid-Supply Voltage
        3. 7.4.3.3 Output Set to Mid-External Reference
        4. 7.4.3.4 Output Set Using Resistor Divider
      4. 7.4.4 High Signal Throughput
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 RSENSE and Device Gain Selection
    2. 8.2 Typical Application
      1. 8.2.1 Inline Motor Current-Sense Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
    3. 8.3 Power Supply Recommendations
      1. 8.3.1 Power Supply Decoupling
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Examples
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.4.2 Reference Pin Connections for Unidirectional Current Measurements

Unidirectional operation allows current measurements through a resistive shunt in one direction. For unidirectional operation, connect the device reference pins together and then to the negative rail (see the Ground Referenced Output section) or the positive rail (see the VS Referenced Output section). The required differential input polarity depends on the reference input setting. The amplifier output moves away from the referenced rail proportional to the current passing through the external shunt resistor. If the amplifier reference pins are connected to the positive rail, then the input polarity must be negative to move the amplifier output down (towards ground). If the amplifier reference pins are connected to ground, then the input polarity must be positive to move the amplifier output up (towards supply).

The following sections describe how to configure the output for unidirectional operation cases.