JAJSOY7A June   2008  – September 2023 TPS2551-Q1

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Revision History
  6. 5 Pin Configurations and Functions
  7. 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
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 機能ブロック図
    3. 8.3 Feature Description
      1. 8.3.1 Overcurrent
      2. 8.3.2 Reverse-Voltage Protection
      3. 8.3.3 FAULT Response
      4. 8.3.4 Undervoltage Lockout (UVLO)
      5. 8.3.5 Enable (EN)
      6. 8.3.6 Thermal Sense
      7. 8.3.7 Device Functional Modes
    4. 8.4 Programming
      1. 8.4.1 Programming the Current-Limit Threshold
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Two-Level Current-Limit Circuit
      2. 9.2.2 Design Requirements
      3. 9.2.3 Detail Design Procedure
        1. 9.2.3.1 Designing Above a Minimum Current Limit
        2. 9.2.3.2 Designing Below a Maximum Current Limit
        3. 9.2.3.3 Input and Output Capacitance
      4. 9.2.4 Auto-Retry Functionality
      5. 9.2.5 Latch-Off Functionality
      6. 9.2.6 Typical Application as USB Power Switch
        1. 9.2.6.1 Design Requirements
          1. 9.2.6.1.1 USB Power-Distribution Requirements
        2. 9.2.6.2 Detail Design Procedure
          1. 9.2.6.2.1 Universal Serial Bus (USB) Power-Distribution Requirements
    3. 9.3 Power Supply Recommendations
      1. 9.3.1 Self-Powered and Bus-Powered Hubs
      2. 9.3.2 Low-Power Bus-Powered and High-Power Bus-Powered Functions
      3. 9.3.3 Power Dissipation and Junction Temperature
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 ドキュメントの更新通知を受け取る方法
    2. 10.2 サポート・リソース
    3. 10.3 Trademarks
    4. 10.4 静電気放電に関する注意事項
    5. 10.5 用語集
  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

8.3.1 Overcurrent

The TPS2551 responds to an overcurrent condition by limiting its output current to the IOC and IOS levels shown in Figure 8-1. Three response profiles are possible depending on the loading conditions and are summarized in Figure 7-3.

One response profile occurs if the TPS2551 is enabled into a short-circuit. The output voltage is held near zero potential with respect to ground and the TPS2551 ramps the output current to IOS (see Figure 6-3).

A second response profile occurs if a short is applied to the output after the TPS2551 is enabled. The device responds to the overcurrent condition within time tIOS (see Figure 7-2). The current-sense amplifier is over-driven during this time and momentarily disables the internal current-limit MOSFET. The current-sense amplifier gradually recovers and limits the output current to IOS.

A third response profile occurs if the load current gradually increases. The device first limits the load current to IOC. If the load demands a current greater than IOC, the TPS2551 folds back the current to IOS and the output voltage decreases to IOS x RLOAD for a resistive load, which is shown in Figure 7-3.

The TPS2551 thermal cycles if an overload condition is present long enough to activate thermal limiting in any of the above cases. The device turns off when the junction temperature exceeds 135°C (typ). The device remains off until the junction temperature cools 15°C (typ) and then restarts. The TPS2551 cycles on/off until the overload is removed (see Figure 6-5 and Figure 6-7) .