JAJSE14B October   2017  – November 2017 TPS23525

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
  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 Switching Characteristics
    7. 6.7 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Relationship between Sense Voltage, Gate Current, and Timer
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Current Limit
        1. 8.3.1.1 Programming the CL Switch-Over Threshold
        2. 8.3.1.2 Programming CL1
        3. 8.3.1.3 Programming CL2
        4. 8.3.1.4 Computing the Fast Trip Threshold
      2. 8.3.2 Soft Start Disconnect
      3. 8.3.3 Timer
      4. 8.3.4 OR-ing
    4. 8.4 Device Functional Modes
      1. 8.4.1 OFF State
      2. 8.4.2 Insertion Delay State
      3. 8.4.3 Start-up State
      4. 8.4.4 Normal Operation State
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1  Selecting RSNS
        2. 9.2.2.2  Selecting Soft Start Setting: CSS and CSS,VEE
        3. 9.2.2.3  Selecting VDS Switch Over Threshold
        4. 9.2.2.4  Timer Selection
        5. 9.2.2.5  MOSFET Selection and SOA Checks
        6. 9.2.2.6  Input Cap, Input TVS, and OR-ing FET selection
        7. 9.2.2.7  EMI Filter Consideration
        8. 9.2.2.8  Under Voltage and Over Voltage Settings
        9. 9.2.2.9  Choosing RVCC and CVCC
        10. 9.2.2.10 Power Good Interface to Downstream DC/DC
      3. 9.2.3 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 関連資料
    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

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

8.3.2 Soft Start Disconnect

The inrush current into the output capacitor (COUT) can be limited by placing a capacitor between the SS (Soft Start) pin and the drain of the hot swap MOSFET. In that case the inrush current can be computed using equation below.

Equation 6. TPS23525 tps23523_equation6.gif

Note that with most hot swap the CSS pin is tied simply to the gate pin, but this can interfere with performance during normal operation if transients or short circuits are encountered. In addition the CSS capacitor tends to pull up the gate during hot plug and cause shoot through current if it is always tied to the gate. For that reason the TPS23525 has a disconnect switch between the gate pin and the SS pin as well as a discharge resistor. During the initial hot plug and during the insertion delay the switch between SS and GATE is open and SS is being discharged to GND through a resistor. Then during start-up SS and GATE are connected to limit the slew rate. Once in normal operation the SS pin is not tied to GATE and it is not shorted to GND, which prevents it from interfering with the operation during transients.

TPS23525 slvsdf9_ss_diagram.gifFigure 9. Implementation of SS Disconnect