JAJSG28F august   2018  – august 2020 TPS2120 , TPS2121

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 Device Comparison Table
  7. 6 Pin Configuration and Functions
    1.     8
  8. 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 Typical Characteristics
  9. 8 Parameter Measurement Information
  10. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Input Settling Time and Output Soft Start Control (SS)
        1. 9.3.1.1 Slew Rate vs. CSS Capacitor
      2. 9.3.2 Active Current Limiting (ILM)
      3. 9.3.3 Short-Circuit Protection
      4. 9.3.4 Thermal Protection (TSD)
      5. 9.3.5 Overvoltage Protection (OVx)
      6. 9.3.6 Fast Reverse Current Blocking (RCB)
      7. 9.3.7 Output Voltage Dip and Fast Switchover Control (TPS2121 only)
      8. 9.3.8 Input Voltage Comparator (VCOMP)
    4. 9.4 TPS2120 Device Functional Modes
    5. 9.5 TPS2121 Device Functional Modes
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Manual Switchover Schematic
      2. 10.2.2 Design Requirements
      3. 10.2.3 Detailed Design Description
      4. 10.2.4 Design Procedure
        1. 10.2.4.1 Selecting PR1 and CP2 Resistors
        2. 10.2.4.2 Selecting OVx Resistors
        3. 10.2.4.3 Selecting Soft-Start Capacitor and Current Limit Resistors
      5. 10.2.5 Application Curves
    3. 10.3 Automatic Switchover with Priority (XCOMP)
      1. 10.3.1 Application Schematic
      2. 10.3.2 Design Requirements
      3. 10.3.3 Detailed Design Description
      4. 10.3.4 Design Procedure
        1. 10.3.4.1 Selecting PR1 and CP2 Resistors
      5. 10.3.5 Application Curves
    4. 10.4 Automatic Seamless Switchover with Priority (XREF)
      1. 10.4.1 Application Schematic
      2. 10.4.2 Design Requirements
      3. 10.4.3 Detailed Design Description
      4. 10.4.4 Application Curves
    5. 10.5 Highest Voltage Operation (VCOMP)
      1. 10.5.1 Application Schematic
      2. 10.5.2 Design Requirements
      3. 10.5.3 Detailed Design Description
      4. 10.5.4 Detailed Design Procedure
      5. 10.5.5 Application Curves
    6. 10.6 Reverse Polarity Protection with TPS212x
    7. 10.7 Hotplugging with TPS212x
  12. 11Power Supply Recommendations
  13. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  14. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Links
    2. 13.2 ドキュメントの更新通知を受け取る方法
    3. 13.3 サポート・リソース
    4. 13.4 Trademarks
    5. 13.5 静電気放電に関する注意事項
    6. 13.6 用語集
  15. 14Mechanical, Packaging, and Orderable Information

9.3.2 Active Current Limiting (ILM)

The load current is monitored at all times. When the load current exceed the current limit trip point ILM programmed by RILM resistor, the device regulates the current within tILM. The following equations can be used to find the RILM value for a desired current limit, where RILM is in kΩ and between 18 kΩ to 100 kΩ.

Equation 1. TPS2120: GUID-08AAF413-E716-4CBE-B72A-AB7BCD9247C9-low.gif
Equation 2. TPS2121: GUID-335A988A-B683-4C0B-ADC1-89FD7D600273-low.gif

During current regulation, the output voltage will drop resulting in increased device power dissipation. If the device junction temperature (TJ) reaches the thermal shutdown threshold (TSD) the internal FETs are turned off. After cooling down, the device will automatically restart.

GUID-314DAA8B-24A5-4020-9824-F17193794032-low.jpgFigure 9-4 Current Limiting Behavior