SLVS850A June   2008  – September 2023 TPS2551-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Pin Configurations and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Overcurrent
      2. 8.3.2 Reverse-Voltage Protection
      3. 8.3.3 FAULT Response
      4. 8.3.4 Undervoltage Lockout (UVLO)
      5. 8.3.5 Enable (EN)
      6. 8.3.6 Thermal Sense
      7. 8.3.7 Device Functional Modes
    4. 8.4 Programming
      1. 8.4.1 Programming the Current-Limit Threshold
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Two-Level Current-Limit Circuit
      2. 9.2.2 Design Requirements
      3. 9.2.3 Detail Design Procedure
        1. 9.2.3.1 Designing Above a Minimum Current Limit
        2. 9.2.3.2 Designing Below a Maximum Current Limit
        3. 9.2.3.3 Input and Output Capacitance
      4. 9.2.4 Auto-Retry Functionality
      5. 9.2.5 Latch-Off Functionality
      6. 9.2.6 Typical Application as USB Power Switch
        1. 9.2.6.1 Design Requirements
          1. 9.2.6.1.1 USB Power-Distribution Requirements
        2. 9.2.6.2 Detail Design Procedure
          1. 9.2.6.2.1 Universal Serial Bus (USB) Power-Distribution Requirements
    3. 9.3 Power Supply Recommendations
      1. 9.3.1 Self-Powered and Bus-Powered Hubs
      2. 9.3.2 Low-Power Bus-Powered and High-Power Bus-Powered Functions
      3. 9.3.3 Power Dissipation and Junction Temperature
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.6 Thermal Sense

The TPS2551 protects itself with two independent thermal sensing circuits that monitor the operating temperature of the power-switch and disables operation if the temperature exceeds recommended operating conditions. The device operates in constant-current mode during an overcurrent conditions, which increases the voltage drop across power-switch. The power dissipation in the package is proportional to the voltage drop across the power-switch, so the junction temperature rises during an overcurrent condition. The first thermal sensor turns off the power-switch when the die temperature exceeds 135°C and the part is in current limit. The second thermal sensor turns off the power-switch when the die temperature exceeds 155°C regardless of whether the power-switch is in current limit. Hysteresis is built into both thermal sensors, and the switch turns on after the device has cooled approximately 15°C. The switch continues to cycle off and on until the fault is removed. The open-drain false reporting output FAULT is asserted (active low) immediately during an overtemperature shutdown condition.