SLUSCD4B March   2017  – May 2018 TPS543C20

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: TPS543C20 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

9.2.2.3 Inductor Selection

To calculate the value of the output inductor (L), use Equation 5. The coefficient KIND represents the amount of inductor-ripple current relative to the maximum output current. The output capacitor filters the inductor-ripple current. Therefore, selecting a high inductor-ripple current impacts the selection of the output capacitor because the output capacitor must have a ripple-current rating equal to or greater than the inductor-ripple current. Generally, the KIND should be kept between 0.1 and 0.3 for balanced performance. Using this target ripple current, the required inductor size can be calculated as shown in Equation 5.

Equation 5. TPS543C20 Eq_L_select_SLUSCD4.gif

A standard inductor value of 470 nH is selected. For this application, Wurth 744309047 was used from the web-orderable EVM.