JAJSJF1B March   2014  – September 2020 TPS2556-Q1 , TPS2557-Q1

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Terminal Configuration and Functions
    1.     Terminal Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 Handling Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Switching Characteristics
    7. 7.7 Typical Characteristics
      1.      16
  8. 8 Parameter Measurement Information
    1.     18
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Overcurrent Conditions
      2. 9.3.2 FAULT Response
      3. 9.3.3 Thermal Sense
    4. 9.4 Device Functional Modes
      1. 9.4.1 Undervoltage Lockout (UVLO)
      2. 9.4.2 Enable ( EN OR EN)
      3. 9.4.3 Auto-Retry Functionality
      4. 9.4.4 Two-Level Current-Limit Circuit
  10. 10Applications and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application, Design for Current Limit
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Determine Design Parameters
        2. 10.2.2.2 Programming the Current-Limit Threshold
        3. 10.2.2.3 Selecting Current-Limit Resistor 1
        4. 10.2.2.4 Selecting Current-Limit Resistor 2
        5. 10.2.2.5 Accounting for Resistor Tolerance
        6. 10.2.2.6 Power Dissipation and Junction Temperature
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
    1.     44
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Related Links
    2. 13.2 Trademarks
    3. 13.3 Electrostatic Discharge Caution
    4. 13.4 Glossary
  14. 14Mechanical, 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

10.2.2.4 Selecting Current-Limit Resistor 2

Some applications require that current limiting must occur below a certain threshold. For this example, assume that the desired upper current-limit threshold must be below 5,000 mA to protect an upstream power supply. Use the IOS equations and Figure 10-2 to select R(ILIM).

Equation 4. GUID-64760087-3DA0-4A9B-8FCC-4D1ED2CF99CE-low.gif

Select the closest 1% resistor greater than the calculated value: R(ILIM) = 23.7 kΩ. This sets the maximum current-limit threshold at 5 000 mA . Use the IOS equations, Figure 10-2, and the previously calculated value for RILIM to calculate the minimum resulting current-limit threshold.

Equation 5. GUID-19865ED1-FDF4-4D34-BD52-091DBB7D5797-low.gif

The resulting minimum current-limit threshold is 4 406 mA with a 23.7-kΩ resistor.