SLVSFJ6A November   2020  – June 2026 TPS27SA08

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Summary Table
  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 Switching Characteristics
    7. 6.7 SNS Timing Characteristics
    8. 6.8 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Protection Mechanisms
        1. 8.3.1.1 Thermal Shutdown
        2. 8.3.1.2 Current Limit
          1. 8.3.1.2.1 Current Limit Foldback
          2. 8.3.1.2.2 Undervoltage Lockout (UVLO)
          3. 8.3.1.2.3 VBB during Short-to-Ground
        3. 8.3.1.3 Energy Limit
        4. 8.3.1.4 Voltage Transients
          1. 8.3.1.4.1 Driving Inductive and Capacitive Loads
        5. 8.3.1.5 Reverse Supply
        6. 8.3.1.6 Fault Event – Timing Diagrams
      2. 8.3.2 Diagnostic Mechanisms
        1. 8.3.2.1 VOUT Short-to-supply and Open-Load
          1. 8.3.2.1.1 Detection With Switch Enabled
          2. 8.3.2.1.2 Detection With Switch Disabled
        2. 8.3.2.2 SNS Output
          1. 8.3.2.2.1 RSNS Value
            1. 8.3.2.2.1.1 High Accuracy Load Current Sense
            2. 8.3.2.2.1.2 SNS Output Filter
        3. 8.3.2.3 ST Pin
        4. 8.3.2.4 Fault Indication and SNS Mux
        5. 8.3.2.5 Resistor Sharing
        6. 8.3.2.6 High-Frequency, Low Duty-Cycle Current Sensing
    4. 8.4 Device Functional Modes
      1. 8.4.1 Off
      2. 8.4.2 Standby
      3. 8.4.3 Diagnostic
      4. 8.4.4 Standby Delay
      5. 8.4.5 Active
      6. 8.4.6 Fault
  10. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Ground Protection Network
      2. 9.1.2 Interface With Microcontroller
      3. 9.1.3 I/O Protection
      4. 9.1.4 Inverse Current
      5. 9.1.5 Loss of GND
      6. 9.1.6 Thermal Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Thermal Considerations
        2. 9.2.2.2 Diagnostics
          1. 9.2.2.2.1 Selecting the RISNS Value
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Related Documentation
    2. 10.2 Trademarks
    3. 10.3 Electrostatic Discharge Caution
    4. 10.4 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

9.1.2 Interface With Microcontroller

The ground protection network causes the device ground to be at a higher potential than the module ground (and microcontroller ground). This offset impacts the interface between the device and the microcontroller.

The forward voltage of the diode offsets the logic pin voltage. For input pins (for example, EN), the designer must consider the VIH specification of the switch and the VOH specification of the microcontroller. For a system that does not include DGND, it is required that VOH > VIH. For a system that does include DGND, it is required that VOH > (VIH + VF). VF is the forward voltage of DGND.

For use of the status pin, ST, a similar consideration is necessary. The designer must consider the VOL, ST specification and the VIL specification of the microcontroller. For a system that includes DGND, it is required that VOL, ST + VF < VIL, µC.

The sense resistor, RSNS, must terminate to the microcontroller ground. In this case, the ADC can accurately measure the SNS signal even if there is an offset between the microcontroller ground and the device ground.