SLVSBD0B November   2012  – June 2020 TPS2553-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Typical Application as USB Power Switch
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Overcurrent Conditions
      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
    4. 8.4 Device Functional Modes
    5. 8.5 Programming
      1. 8.5.1 Programming the Current-Limit Threshold
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Constant-Current and Impact on Output Voltage
      2. 9.1.2 Accounting for Resistor Tolerance
      3. 9.1.3 Input and Output Capacitance
    2. 9.2 Typical Applications
      1. 9.2.1 Application 1: Designing Above a Minimum Current-Limit
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Application 2: Designing Below a Maximum Current-Limit
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
      3. 9.2.3 Application 3: Auto-Retry Functionality
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Detailed Design Procedure
      4. 9.2.4 Application 4: Two-Level Current-Limit Circuit
        1. 9.2.4.1 Design Requirements
        2. 9.2.4.2 Detailed Design Procedure
      5. 9.2.5 Application 5: Typical Application as USB Power Switch
        1. 9.2.5.1 Design Requirements
        2. 9.2.5.2 Detailed Design Procedure
          1. 9.2.5.2.1 Universal Serial Bus (USB) Power-Distribution Requirements
  10. 10Power Supply Recommendations
    1. 10.1 USB Self-Powered (SPH) and Bus-Powered (BPH) Hubs
    2. 10.2 USB Low-Power Bus-Powered and High-Power Bus-Powered Functions
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Power Dissipation and Junction Temperature
  12. 12Device and Documentation Support
    1. 12.1 Device Support
    2. 12.2 Support Resource
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

9.2.5.1 Design Requirements

For this example, use the parameters shown in Table 6.

Table 6. Design Requirements

PARAMETER VALUE
Input voltage 5 V
Output voltage 5 V
Above a minimum current limit 500 mA

USB can be implemented in several ways regardless of the type of USB device being developed. Several power-distribution features must be implemented.

  • Self-powered hubs (SPHs) must:
    • current-limit downstream ports
    • Report overcurrent conditions
  • BPHs must:
    • Enable and disable power to downstream ports
    • Power up at <100 mA
    • Limit inrush current (<44 Ω and 10 μF)
  • Functions must:
    • Limit inrush currents
    • Power up at <100 mA

The feature set of the TPS2553-Q1 device meets each of these requirements. The integrated current-limiting and overcurrent reporting is required by self-powered hubs. The logic-level enable and controlled rise times meet the need of both input and output ports on USB-powered hubs and the input ports for USB-powered functions.