ZHCSHI4D January   2018  – December 2019 TPS25221

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     Device Images
      1.      简化原理图
  4. 4 修订历史记录
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 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
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Over-current Conditions
      2. 9.3.2 Fault Response
      3. 9.3.3 Undervoltage Lockout (UVLO)
      4. 9.3.4 Enable, (EN)
      5. 9.3.5 Thermal Sense
    4. 9.4 Device Functional Modes
    5. 9.5 Programming
      1. 9.5.1 Programming the Current-Limit Threshold
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Constant-Current
    2. 10.2 Typical Applications
      1. 10.2.1 Two-Level Current-Limit Circuit
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedures
          1. 10.2.1.2.1 Designing Above a Minimum Current Limit
          2. 10.2.1.2.2 Designing Below a Maximum Current Limit
          3. 10.2.1.2.3 Accounting for Resistor Tolerance
          4. 10.2.1.2.4 Input and Output Capacitance
        3. 10.2.1.3 Application Curve
      2. 10.2.2 Auto-Retry Functionality
        1. 10.2.2.1 Design Requirements (added)
        2. 10.2.2.2 Detailed Design Procedure
      3. 10.2.3 Typical Application as USB Power Switch
        1. 10.2.3.1 Design Requirements
          1. 10.2.3.1.1 USB Power-Distribution Requirements
        2. 10.2.3.2 Detailed Design Procedure
          1. 10.2.3.2.1 Universal Serial Bus (USB) Power-Distribution Requirements
  11. 11Power Supply Recommendations
    1. 11.1 Self-Powered and Bus-Powered Hubs
    2. 11.2 Low-Power Bus-Powered and High-Power Bus-Powered Functions
    3. 11.3 Power Dissipation and Junction Temperature
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13器件和文档支持
    1. 13.1 器件支持
      1. 13.1.1 第三方产品免责声明
    2. 13.2 文档支持
      1. 13.2.1 相关文档
    3. 13.3 接收文档更新通知
    4. 13.4 社区资源
    5. 13.5 商标
    6. 13.6 静电放电警告
    7. 13.7 Glossary
  14. 14机械、封装和可订购信息

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

10.2.1.2.1 Designing Above a Minimum Current Limit

Some applications require that current limiting cannot occur below a certain threshold. For this example, assume that 1 A must be delivered to the load so that the minimum desired current-limit threshold is 1000 mA. Use the IOS equations and Figure 24 to select RILIM.

Equation 3. TPS25221 eq_app1_1st_slvsdt3.gif

Select the closest 1% resistor less than the calculated value: RILIM = 49.9 kΩ. This sets the minimum current-limit threshold at 1 A . Use the IOS equations, Figure 24, and the previously calculated value for RILIM to calculate the maximum resulting current-limit threshold.

Equation 4. TPS25221 eq_app1_2nd_slvsdt3.gif

The resulting maximum current-limit threshold is 1186 mA with a 49.9 kΩ resistor.