SLUS710E May   2006  – January 2024 TPS28225

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Switching Characteristics
    7. 5.7 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Undervoltage Lockout (UVLO)
      2. 6.3.2 Output Active Low
      3. 6.3.3 Enable/Power Good
      4. 6.3.4 3-State Input
        1. 6.3.4.1 TPS28225 3-State Exit Mode
        2. 6.3.4.2 External Resistor Interference
      5. 6.3.5 Bootstrap Diode
      6. 6.3.6 Upper and Lower Gate Drivers
      7. 6.3.7 Dead-Time Control
      8. 6.3.8 Thermal Shutdown
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Four Phases Driven by TPS28225 Driver
        2. 7.2.2.2 Switching The MOSFETs
        3. 7.2.2.3 List of Materials
      3. 7.2.3 Application Curves
    3. 7.3 System Examples
  9. 8 Power Supply Recommendations
  10. 9 Layout
    1. 9.1 Layout Guidelines
    2. 9.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

6.3.5 Bootstrap Diode

The bootstrap diode provides the supply voltage for the UGATE driver by charging the bootstrap capacitor connected between BOOT and PHASE pins from the input voltage VDD when the low-side FET is in ON state. At the very initial stage when both power FETs are OFF, the bootstrap capacitor is pre-charged through this path including the PHASE pin, output inductor and large output capacitor down to GND. The forward voltage drop across the diode is only 1.0 V at bias current 100 mA. This allows quick charge restore of the bootstrap capacitor during the high-frequency operation.