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

パッケージ・オプション

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メカニカル・データ（パッケージ｜ピン）
  • YFP|20
サーマルパッド・メカニカル・データ
発注情報

10.4.3 Detailed Design Description

In the second example, the system seamlessly switches between two 12-V supplies, providing uninterrupted power to a downstream load. Priority is given to IN1, the main 12-V power rail, and switches over to IN2, the backup 12-V power rail, whenever IN1 dips. When the main power rail returns, the device will switch back to the main supply. Redundant power is critical in systems that require uninterrupted sources of power. If the output voltage were to dip on these systems, this could cause the downstream load to reset to enter an undervoltage lockout condition. Therefore, the TPS2121 will be used in fast switchover mode to minimize the output voltage dip.

Similar to the automatic switchover example shown above, the TPS2121 can be configured in XCOMP mode. However, to minimize the voltage switchover error for a more seamless switchover, an external precision regulator can be connected to CP2 in XREF mode. In this configuration, a REF3325 provides an external reference voltage on 2.5 V ± 0.15% (2.50375V). If the voltage on PR1 is higher than this external reference, priority will be given to IN1. If the voltage on PR1 drops below 2.50375V, then the device will switchover to IN2.

The design specifications detail the input voltage range for 12.1 ± 3%. Therefore, the resistor divider on PR1 is configured such that the voltage on the pin dips below 2.50375V before IN1 crosses 11.73 V (12.1 V – 3%). Once this occurs, the design will start fast switchover to IN2 within 5 us.

For additional information regarding this configuration, including full design procedures, schematics, and layout, please refer to TIDA-01638: Seamless Switchover for Backup Power Reference Design.