SLVS736C February   2008  – October 2023 TPS2550 , TPS2551

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  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 Overcurrent
      2. 9.3.2 Reverse-Voltage Protection
      3. 9.3.3 FAULT Response
      4. 9.3.4 Undervoltage Lockout (UVLO)
      5. 9.3.5 ENABLE ( EN or EN)
      6. 9.3.6 Thermal Sense
      7. 9.3.7 Device Functional Modes
    4. 9.4 Programming
      1. 9.4.1 Programming the Current-Limit Threshold
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Two-Level Current-Limit Circuit
      2. 10.2.2 Design Requirements
      3. 10.2.3 Detail Design Procedures
        1. 10.2.3.1 Designing Above a Minimum Current Limit
        2. 10.2.3.2 Designing Below a Maximum Current Limit
        3. 10.2.3.3 Input and Output Capacitance
      4. 10.2.4 Auto-Retry Functionality
      5. 10.2.5 Latch-Off Functionality
      6. 10.2.6 Typical Application as USB Power Switch
        1. 10.2.6.1 Design Requirements
          1. 10.2.6.1.1 USB Power-Distribution Requirements
        2. 10.2.6.2 Detail Design Procedures
          1. 10.2.6.2.1 Universal Serial Bus (USB) Power-Distribution Requirements
    3. 10.3 Power Supply Recommendations
      1. 10.3.1 Self-Powered and Bus-Powered Hubs
      2. 10.3.2 Low-Power Bus-Powered and High-Power Bus-Powered Functions
      3. 10.3.3 Power Dissipation and Junction Temperature
    4. 10.4 Layout
      1. 10.4.1 Layout Guidelines
      2. 10.4.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

10.2.4 Auto-Retry Functionality

Some applications require that an overcurrent condition disables the part momentarily during a fault condition and re-enables after a pre-set time. This auto-retry functionality can be implemented with an external resistor and capacitor. During a fault condition, FAULT pulls low disabling the part. The part is disabled when EN is pulled low, and FAULT goes high impedance allowing CRETRY to begin charging. The part re-enables when the voltage on EN reaches the turnon threshold, and the auto-retry time is determined by the resistor/capacitor time constant. The part continues to cycle in this manner until the fault condition is removed.

GUID-30E22B7F-E01F-4CDF-893A-3E9222A18544-low.gifFigure 10-2 Auto-Retry Functionality

Some applications require auto-retry functionality and the ability to enable/disable with an external logic signal. The figure below shows how an external logic signal can drive EN through RFAULT and maintain auto-retry functionality. The resistor/capacitor time constant determines the auto-retry time-out period.

GUID-1A55D9F9-4C46-49D0-998E-A06BE815A2EF-low.gifFigure 10-3 Auto-Retry Functionality With External EN Signal