JAJSPC8C December   2022  – February 2024 TPSM33615 , TPSM33625

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 絶対最大定格
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 電気的特性
    6. 6.6 System Characteristics
    7. 6.7 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Input Voltage Range
      2. 7.3.2  Output Voltage Selection
      3. 7.3.3  Input Capacitors
      4. 7.3.4  Output Capacitors
      5. 7.3.5  Enable, Start-Up, and Shutdown
      6. 7.3.6  External CLK SYNC (with MODE/SYNC)
        1. 7.3.6.1 Pulse-Dependent MODE/SYNC Pin Control
      7. 7.3.7  Switching Frequency (RT)
      8. 7.3.8  Power-Good Output Operation
      9. 7.3.9  Internal LDO, VCC and VOUT/FB Input
      10. 7.3.10 Bootstrap Voltage and VBOOT-UVLO (BOOT Terminal)
      11. 7.3.11 Spread Spectrum
      12. 7.3.12 Soft Start and Recovery from Dropout
        1. 7.3.12.1 Recovery from Dropout
      13. 7.3.13 Overcurrent Protection (Hiccup Mode)
      14. 7.3.14 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode
        1. 7.4.3.1 CCM Mode
        2. 7.4.3.2 Auto Mode – Light-Load Operation
          1. 7.4.3.2.1 Diode Emulation
          2. 7.4.3.2.2 Frequency Reduction
        3. 7.4.3.3 FPWM Mode – Light-Load Operation
        4. 7.4.3.4 Minimum On-Time (High Input Voltage) Operation
        5. 7.4.3.5 Dropout
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1  Custom Design With WEBENCH® Tools
        2. 8.2.2.2  Choosing the Switching Frequency
        3. 8.2.2.3  Setting the Output Voltage
        4. 8.2.2.4  Input Capacitor Selection
        5. 8.2.2.5  Output Capacitor Selection
        6. 8.2.2.6  VCC
        7. 8.2.2.7  CFF Selection
        8. 8.2.2.8  Power Good Signal
        9. 8.2.2.9  Maximum Ambient Temperature
        10. 8.2.2.10 Other Connections
      3. 8.2.3 Application Curves
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
        1. 8.5.1.1 Ground and Thermal Considerations
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 サード・パーティ製品に関する免責事項
      2. 9.1.2 Development Support
        1. 9.1.2.1 Custom Design With WEBENCH® Tools
      3. 9.1.3 Device Nomenclature
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 ドキュメントの更新通知を受け取る方法
    4. 9.4 サポート・リソース
    5. 9.5 Trademarks
    6. 9.6 静電気放電に関する注意事項
    7. 9.7 用語集
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

8.2.2.7 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. Optimizing Transient Response of Internally Compensated DC-DC Converters with Feedforward Capacitor application report is helpful when experimenting with a feedforward capacitor.

Due to the nature of the feedback detect circuitry, the value of CFF must be limited to ensure that the desired output voltage is established when configuring for adjustable output voltages. Equation 13 must be followed to ensure CFF remains below the maximum value.

Equation 13. CFF<COUT×VOUT1.2×106