JAJSH85B April   2019  – April 2019 TPS566235

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      代表的なアプリケーション
      2.      効率と出力電流との関係、Eco-mode
  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 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 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 PWM Operation and D-CAP3 Control
      2. 7.3.2 Power Good
      3. 7.3.3 Soft Start and Pre-Biased Soft Start
      4. 7.3.4 Over current Protection and Undervoltage Protection
      5. 7.3.5 Over Voltage Protection
      6. 7.3.6 UVLO Protection
      7. 7.3.7 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Light Load Operation
      2. 7.4.2 MODE Pin Configuration
      3. 7.4.3 Advanced Eco-Mode Control
      4. 7.4.4 Out-Of-Audio Mode
      5. 7.4.5 Force CCM Mode
      6. 7.4.6 Standby 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 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Inductor Selection
        3. 8.2.2.3 Output Capacitor Selection
        4. 8.2.2.4 Input 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 デバイス・サポート
      1. 11.1.1 デベロッパー・ネットワークの製品に関する免責事項
      2. 11.1.2 開発サポート
        1. 11.1.2.1 WEBENCH®ツールによるカスタム設計
    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

7.3.3 Soft Start and Pre-Biased Soft Start

The TPS566235 has an internal 1.0 ms soft-start time. Soft start can prevent the overshoot of output voltage during start up. When the EN pin becomes high, internal soft-start function begins ramping up the reference voltage to the PWM comparator.

The TPS566235 can prevent current from being pulled from the output during startup if the output is pre-biased. The device disables the switching of both the high-side and low-side FETs until the soft-start commands a voltage higher than the pre-bias level (internal soft start becomes greater than feedback voltage VFB). Then, the controller start the first high side FET gate driver pulses. This scheme prevents the initial sinking of the pre-bias output, and ensure that the output voltage starts and ramps up into regulation and the control loop is given time to transition from pre-biased start-up to normal mode operation.