SLUSDE0 December   2018 TPS543C20A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Device Comparison Table
  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 Thermal Information
    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
    4. 8.4 Device Functional Modes
      1. 8.4.1  Soft-Start Operation
      2. 8.4.2  Input and VDD Undervoltage Lockout (UVLO) Protection
      3. 8.4.3  Power Good and Enable
      4. 8.4.4  Voltage Reference
      5. 8.4.5  Prebiased Output Start-up
      6. 8.4.6  Internal Ramp Generator
        1. 8.4.6.1 Ramp Selections
      7. 8.4.7  Switching Frequency
      8. 8.4.8  Clock Sync Point Selection
      9. 8.4.9  Synchronization and Stackable Configuration
      10. 8.4.10 Dual-Phase Stackable Configurations
        1. 8.4.10.1 Configuration 1: Master Sync Out Clock-to-Slave
        2. 8.4.10.2 Configuration 2: Master and Slave Sync to External System Clock
      11. 8.4.11 Operation Mode
      12. 8.4.12 API/Body Brake
      13. 8.4.13 Sense and Overcurrent Protection
        1. 8.4.13.1 Low-Side MOSFET Overcurrent Protection
        2. 8.4.13.2 High-Side MOSFET Overcurrent Protection
      14. 8.4.14 Output Overvoltage and Undervoltage Protection
      15. 8.4.15 Overtemperature Protection
      16. 8.4.16 RSP/RSN Remote Sense Function
      17. 8.4.17 Current Sharing
      18. 8.4.18 Loss of Synchronization
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application: TPS543C20A Stand-alone Device
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Custom Design With WEBENCH® Tools
        2. 9.2.2.2 Switching Frequency Selection
        3. 9.2.2.3 Inductor Selection
        4. 9.2.2.4 Input Capacitor Selection
        5. 9.2.2.5 Bootstrap Capacitor Selection
        6. 9.2.2.6 BP Pin
        7. 9.2.2.7 R-C Snubber and VIN Pin High-Frequency Bypass
        8. 9.2.2.8 Output Capacitor Selection
          1. 9.2.2.8.1 Response to a Load Transient
          2. 9.2.2.8.2 Ramp Selection Design to Ensure Stability
      3. 9.2.3 Application Curves
    3. 9.3 System Example
      1. 9.3.1 Two-Phase Stackable
        1. 9.3.1.1 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Package Size, Efficiency and Thermal Performance
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
        1. 12.1.1.1 Custom Design With WEBENCH® Tools
      2. 12.1.2 Documentation Support
        1. 12.1.2.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.2.2 Switching Frequency Selection

Select a switching frequency for the TPS543C20A. There is a trade off between higher and lower switching frequencies. Higher switching frequencies may produce smaller solution size using lower valued inductors and smaller output capacitors compared to a power supply that switches at a lower frequency. However, the higher switching frequency causes extra switching losses, which decrease efficiency and impact thermal performance. In this design, a moderate switching frequency of 500 kHz achieves both a small solution size and a high efficiency operation is selected. The device supports continuous switching frequency programming; see Equation 4. additional considerations (internal ramp compensation) other than switching frequency need to be included.

Equation 4. TPS543C20A Eq_Rrt_3_SLUSCD4.gif

In this case, a standard resistor value of 40.2 kΩ is selected.