SLUS886B NOVEMBER   2008  – June 2019 TPS40197

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Typical Application Circuit
  4. 4 Revision History
  5. 5 Description Continued
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Package Dissipation Ratings
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Enable
      2. 8.3.2  Oscillator
      3. 8.3.3  UVLO
      4. 8.3.4  Start-up Sequence and Timing
      5. 8.3.5  Selecting the Short Circuit Current
      6. 8.3.6  Voltage Reference and Dynamic VID
      7. 8.3.7  Minimum On-Time Consideration
      8. 8.3.8  BP Regulator
      9. 8.3.9  Prebias Start-up
      10. 8.3.10 Drivers
      11. 8.3.11 Power Good
      12. 8.3.12 Thermal Shutdown
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
  10. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
    2. 10.2 Documentation Support
      1. 10.2.1 Related Devices
      2. 10.2.2 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Community Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

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

5 Description Continued

Short-circuit detection is done by sensing the voltage drop across the low-side FET when it is on and comparing it with a user selected threshold of 100 mV, 200 mV or 280 mV. The threshold is set with a single external resistor connected from COMP to GND. This resistor is sensed at startup and the selected threshold is latched. Pulse by pulse limiting (to prevent current runaway) is provided by sensing the voltage across the high-side FET when it is on and terminating the cycle when the voltage drop rises above a fixed threshold of 550 mV. When the controller senses an output short circuit, both FETs are turned off and a timeout period is observed before attempting to restart. This provides limited power dissipation in the event of a sustained fault.