JAJSBM0F November   2011  – October 2021 TPS62140 , TPS62140A , TPS62141 , TPS62142 , TPS62143

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings (1)
    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 Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Enable/Shutdown (EN)
      2. 8.3.2 Soft-Start/Tracking (SS/TR)
      3. 8.3.3 Power Good (PG)
      4. 8.3.4 Pin-Selectable Output Voltage (DEF)
      5. 8.3.5 Frequency Selection (FSW)
      6. 8.3.6 Undervoltage Lockout (UVLO)
      7. 8.3.7 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Pulse-Width Modulation (PWM) Operation
      2. 8.4.2 Power Save Mode Operation
      3. 8.4.3 100% Duty-Cycle Operation
      4. 8.4.4 Current Limit and Short Circuit Protection
  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
        1. 9.2.2.1 Programming the Output Voltage
        2. 9.2.2.2 External Component Selection
          1. 9.2.2.2.1 Inductor Selection
          2. 9.2.2.2.2 Capacitor Selection
            1. 9.2.2.2.2.1 Output Capacitor
            2. 9.2.2.2.2.2 Input Capacitor
            3. 9.2.2.2.2.3 Soft-Start Capacitor
        3. 9.2.2.3 Tracking Function
        4. 9.2.2.4 Output Filter and Loop Stability
      3. 9.2.3 Application Curves
    3. 9.3 System Examples
      1. 9.3.1 LED Power Supply
      2. 9.3.2 Active Output Discharge
      3. 9.3.3 Inverting Power Supply
      4. 9.3.4 Various Output Voltages
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Thermal Considerations
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 サポート・リソース
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

9.3.3 Inverting Power Supply

The TPS6214x can be used as inverting power supply by rearranging external circuitry as shown in Figure 9-42. As the former GND node now represents a voltage level below system ground, the voltage difference between VIN and VOUT has to be limited for operation to the maximum supply voltage of 17V (see Equation 16).

Equation 16. GUID-EB2AAD2A-C899-46BF-A562-F90F5B13DEC7-low.gif

GUID-EC319352-97D1-48A7-B6E0-F2AF4143D529-low.gifFigure 9-42 –3.3V Inverting Power Supply

The transfer function of the inverting power supply configuration differs from the buck mode transfer function, incorporating a Right Half Plane Zero additionally. The loop stability has to be adapted and an output capacitance of at least 22µF is recommended. A detailed design example is given in Using the TPS6215x in an Inverting Buck-Boost Topology Application Report.