JAJSCQ2B November   2016  – June 2018 TPS54200 , TPS54201

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      概略回路図
      2.      ADIMでの優れた深調光機能
  4. 4 改訂履歴
  5. 5 概要（続き）
  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 Timing Requirements
    7. 7.7 Switching Characteristics
    8. 7.8 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Fixed-Frequency PWM Control
      2. 8.3.2  Error Amplifier
      3. 8.3.3  Slope Compensation and Output Current
      4. 8.3.4  Input Undervoltage Lockout
      5. 8.3.5  Voltage Reference
      6. 8.3.6  Setting LED Current
      7. 8.3.7  Internal Soft Start
      8. 8.3.8  Bootstrap Voltage (BOOT)
      9. 8.3.9  Overcurrent Protection
        1. 8.3.9.1 High-Side MOSFET Overcurrent Protection
        2. 8.3.9.2 Low-Side MOSFET Overcurrent Protection
        3. 8.3.9.3 Low-Side MOSFET Reverse Overcurrent Protection
      10. 8.3.10 Fault Protection
        1. 8.3.10.1 LED-Open Protection
        2. 8.3.10.2 LED Short Protection
        3. 8.3.10.3 Sense-Resistor Short Protection
        4. 8.3.10.4 Sense-Resistor Open Protection
        5. 8.3.10.5 Overvoltage Protection
        6. 8.3.10.6 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Enable and Disable Device
      2. 8.4.2 Mode Detection
      3. 8.4.3 Analog Dimming Mode Operation
      4. 8.4.4 PWM Dimming-Mode Operation
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 TPS5420x 12-V Input, 1.5-A, 3-Piece IR LED Driver With Analog Dimming
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Inductor Selection
          2. 9.2.1.2.2 Input Capacitor Selection
          3. 9.2.1.2.3 Output Capacitor Selection
          4. 9.2.1.2.4 FB Pin RC Filter Selection
          5. 9.2.1.2.5 Sense Resistor Selection
        3. 9.2.1.3 Application Curves
      2. 9.2.2 TPS5420x 24-V Input, 1-A, 4-Piece WLED Driver With PWM Dimming
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 Inductor Selection
          2. 9.2.2.2.2 Input Capacitor Selection
          3. 9.2.2.2.3 Output Capacitor Selection
          4. 9.2.2.2.4 FB Pin RC Filter Selection
          5. 9.2.2.2.5 Sense Resistor Selection
        3. 9.2.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12デバイスおよびドキュメントのサポート
    1. 12.1 デバイス・サポート
      1. 12.1.1 デベロッパー・ネットワークの製品に関する免責事項
    2. 12.2 ドキュメントのサポート
      1. 12.2.1 関連リンク
    3. 12.3 ドキュメントの更新通知を受け取る方法
    4. 12.4 コミュニティ・リソース
    5. 12.5 商標
    6. 12.6 静電気放電に関する注意事項
    7. 12.7 Glossary
  13. 13メカニカル、パッケージ、および注文情報

9.2.1.2.5 Sense Resistor Selection

The maximum target LED current at 100% PWM duty is 1.5 A, and the corresponding VREF is 200 mV. Using Equation 1, calculate the needed sense resistance at 133 mΩ. Pay close attention to the power consumption of the sense resistor in this design at 300 mW, and make sure the chosen resistor has enough margin in its power rating.