SLUSEA4D June   2021  – August 2022 TPS62932 , TPS62933 , TPS62933F , TPS62933O , TPS62933P

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Fixed Frequency Peak Current Mode
      2. 9.3.2  Pulse Frequency Modulation
      3. 9.3.3  Voltage Reference
      4. 9.3.4  Output Voltage Setting
      5. 9.3.5  Switching Frequency Selection
      6. 9.3.6  Enable and Adjusting Undervoltage Lockout
      7. 9.3.7  External Soft Start and Prebiased Soft Start
      8. 9.3.8  Power Good
      9. 9.3.9  Minimum On Time, Minimum Off Time, and Frequency Foldback
      10. 9.3.10 Frequency Spread Spectrum
      11. 9.3.11 Overvoltage Protection
      12. 9.3.12 Overcurrent and Undervoltage Protection
      13. 9.3.13 Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Modes Overview
      2. 9.4.2 Heavy Load Operation
      3. 9.4.3 Light Load Operation
      4. 9.4.4 Out of Audio Operation
      5. 9.4.5 Forced Continuous Conduction Operation
      6. 9.4.6 Dropout Operation
      7. 9.4.7 Minimum On-Time Operation
      8. 9.4.8 Shutdown Mode
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1  Custom Design With WEBENCH® Tools
        2. 10.2.2.2  Output Voltage Resistors Selection
        3. 10.2.2.3  Choosing Switching Frequency
        4. 10.2.2.4  Soft-Start Capacitor Selection
        5. 10.2.2.5  Bootstrap Capacitor Selection
        6. 10.2.2.6  Undervoltage Lockout Setpoint
        7. 10.2.2.7  Output Inductor Selection
        8. 10.2.2.8  Output Capacitor Selection
        9. 10.2.2.9  Input Capacitor Selection
        10. 10.2.2.10 Feedforward Capacitor CFF Selection
        11. 10.2.2.11 Maximum Ambient Temperature
      3. 10.2.3 Application Curves
    3. 10.3 What to Do and What Not to Do
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
      2. 13.1.2 Development Support
        1. 13.1.2.1 Custom Design With WEBENCH® Tools
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Support Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

10.2.2.10 Feedforward Capacitor CFF Selection

In some cases, a feedforward capacitor can be used across RFBT to improve the load transient response or improve the loop phase margin. This is especially true when values of RFBT > 100 kΩ are used. Large values of RFBT in combination with the parasitic capacitance at the FB pin can create a small signal pole that interferes with the loop stability. A CFF helps mitigate this effect. Use lower values to determine if any advantage is gained by the use of a CFF capacitor.

The Optimizing Transient Response of Internally Compensated DC-DC Converters with Feedforward Capacitor Application Report is helpful when experimenting with a feedforward capacitor.

For this example design, a 10-pF capacitor C9 can be mounted to boost load transient performance.