JAJSFQ3A July   2018  – September 2019 TPS56637

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.      効率と出力電流との関係 VOUT = 5V
  4. 4 改訂履歴
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Handling Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  The Adaptive On-Time Control and PWM Operation
      2. 7.3.2  Mode Selection
        1. 7.3.2.1 Eco-mode™ Control Scheme
        2. 7.3.2.2 FCCM Control
      3. 7.3.3  Soft Start and Pre-Biased Soft Start
      4. 7.3.4  Enable and Adjusting Undervoltage Lockout
      5. 7.3.5  Output Overcurrent Limit and Undervoltage Protection
      6. 7.3.6  Overvoltage Protection
      7. 7.3.7  UVLO Protection
      8. 7.3.8  Thermal Shutdown
      9. 7.3.9  Output Voltage Discharge
      10. 7.3.10 Power Good
    4. 7.4 Device Functional Modes
      1. 7.4.1 Standby Operation
      2. 7.4.2 Normal Operation
      3. 7.4.3 Light Load Operation
  8. 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 Output Voltage Resistors Selection
        2. 8.2.2.2 Output Filter Selection
        3. 8.2.2.3 Input Capacitor Selection
        4. 8.2.2.4 Bootstrap Capacitor Selection
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11デバイスおよびドキュメントのサポート
    1. 11.1 ドキュメントのサポート
      1. 11.1.1 関連資料
    2. 11.2 ドキュメントの更新通知を受け取る方法
    3. 11.3 コミュニティ・リソース
    4. 11.4 商標
    5. 11.5 静電気放電に関する注意事項
    6. 11.6 Glossary
  12. 12メカニカル、パッケージ、および注文情報
    1. 12.1 Package Option Addendum
      1. 12.1.1 Packaging Information
      2. 12.1.2 Tape and Reel Information

8.2.2.1 Output Voltage Resistors Selection

The output voltage is set with a resistor divider from the output node to the VFB pin. TI recommends to use 1% tolerance or better divider resistors. Start by using Equation 5 to calculate VOUT. R5 is optional and can be used to measure the control loop's frequency response.

To improve efficiency at very light loads consider using larger value resistors. If the resistance is too high the device will be more susceptible to noise and voltage errors from the VFB input current will be more noticeable. Please note that dynamically adjusting output voltage is not recommended.

Equation 5. TPS56637 equation-4-slvseg1.gif