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

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DBV|6
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.2.5.2.1 Universal Serial Bus (USB) Power-Distribution Requirements

One application for this device is for current-limiting in universal serial bus (USB) applications. The original USB interface was a 12-Mb/s or 1.5-Mb/s, multiplexed serial bus designed for low-to-medium bandwidth PC peripherals (for example: keyboards, printers, scanners, and mice). As the demand for more bandwidth increased, the USB 2.0 standard was introduced increasing the maximum data rate to 480-Mb/s. The four-wire USB interface is conceived for dynamic attach-detach (hot plug-unplug) of peripherals. Two lines are provided for differential data, and two lines are provided for 5-V power distribution.

USB data is a 3.3-V level signal, but power is distributed at 5 V to allow for voltage drops in cases where power is distributed through more than one hub across long cables. Each function must provide its own regulated 3.3 V from the 5-V input or its own internal power supply. The USB specification classifies two different classes of devices depending on its maximum current draw. A device classified as low-power can draw up to 100 mA as defined by the standard. A device classified as high-power can draw up to 500 mA. It is important that the minimum current-limit threshold of the current-limiting power-switch exceed the maximum current-limit draw of the intended application. The latest USB standard should always be referenced when considering the current-limit threshold.

The USB specification defines two types of devices as hubs and functions. A USB hub is a device that contains multiple ports for different USB devices to connect and can be a self-powered hub (SPH) or bus-powered hub (BPH). A function is a USB device that is able to transmit or receive data or control information over the bus. A USB function can be embedded in a USB hub. A USB function can be one of three types included in the list below.

  • Low-power, bus-powered function
  • High-power, bus-powered function
  • Self-powered function

SPHs and BPHs distribute data and power to downstream functions. The TPS2553-Q1 device has higher current capability than required for a single USB port allowing it to power multiple downstream ports.

See Programming the Current-Limit Threshold for the current limit setting. Using those calculations, the current limit may be set using RILIM. For this application, the current limit has been set above 1000 mA to allow for addition loading from the USB port.