SLVSH68B June   2023  – June 2024 TPS543B25T

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 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. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  VIN Pins and VIN UVLO
      2. 6.3.2  Internal Linear Regulator and Bypassing
      3. 6.3.3  Enable and Adjustable UVLO
        1. 6.3.3.1 Internal Sequence of Events During Start-Up
      4. 6.3.4  Switching Frequency Selection
      5. 6.3.5  Switching Frequency Synchronization to an External Clock
        1. 6.3.5.1 Internal PWM Oscillator Frequency
        2. 6.3.5.2 Loss of Synchronization
        3. 6.3.5.3 Interfacing the SYNC/FSEL Pin
      6. 6.3.6  Remote Sense Amplifier and Adjusting the Output Voltage
      7. 6.3.7  Loop Compensation Guidelines
        1. 6.3.7.1 Output Filter Inductor Tradeoffs
        2. 6.3.7.2 Ramp Capacitor Selection
        3. 6.3.7.3 Output Capacitor Selection
        4. 6.3.7.4 Design Method for Good Transient Response
      8. 6.3.8  Soft Start and Prebiased Output Start-Up
      9. 6.3.9  MSEL Pin
      10. 6.3.10 Power Good (PG)
      11. 6.3.11 Output Overload Protection
        1. 6.3.11.1 Positive Inductor Current Protection
        2. 6.3.11.2 Negative Inductor Current Protection
      12. 6.3.12 Output Overvoltage and Undervoltage Protection
      13. 6.3.13 Overtemperature Protection
      14. 6.3.14 Output Voltage Discharge
    4. 6.4 Device Functional Modes
      1. 6.4.1 Forced Continuous-Conduction Mode
      2. 6.4.2 Discontinuous Conduction Mode During Soft Start
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 1.0V Output, 1MHz Application
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
          1. 7.2.1.2.1  Custom Design With WEBENCH® Tools
          2. 7.2.1.2.2  Switching Frequency
          3. 7.2.1.2.3  Output Inductor Selection
          4. 7.2.1.2.4  Output Capacitor
          5. 7.2.1.2.5  Input Capacitor
          6. 7.2.1.2.6  Adjustable Undervoltage Lockout
          7. 7.2.1.2.7  Output Voltage Resistors Selection
          8. 7.2.1.2.8  Bootstrap Capacitor Selection
          9. 7.2.1.2.9  VDRV and VCC Capacitor Selection
          10. 7.2.1.2.10 PGOOD Pullup Resistor
          11. 7.2.1.2.11 Current Limit Selection
          12. 7.2.1.2.12 Soft-Start Time Selection
          13. 7.2.1.2.13 Ramp Selection and Control Loop Stability
          14. 7.2.1.2.14 MODE Pin
        3. 7.2.1.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
      3. 7.4.3 Thermal Performance
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 Custom Design With WEBENCH® Tools
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

6.3.14 Output Voltage Discharge

When the TPS543B25T is enabled, but the high-side FET and low-side FET are disabled due to a fault condition, the output voltage discharge mode is enabled, turning on the discharge FET from SW to PGND to discharge the output voltage. The discharge FET is turned off when the converter is ready to resume switching, either after the fault clears or after the wait time before hiccup is over.

The output voltage discharge mode is activated by any of the following fault events:

  • High-side or low-side positive overcurrent
  • Thermal shutdown
  • Output voltage undervoltage
  • VIN UVLO