SLVS757E March   2007  – July 2022 TPS5450

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  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 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Oscillator Frequency
      2. 7.3.2  Voltage Reference
      3. 7.3.3  Enable (ENA) and Internal Slow-Start
      4. 7.3.4  Undervoltage Lockout (UVLO)
      5. 7.3.5  Boost Capacitor (BOOT)
      6. 7.3.6  Output Feedback (VSENSE) and Internal Compensation
      7. 7.3.7  Voltage Feed-Forward
      8. 7.3.8  Pulse-Width-Modulation (PWM) Control
      9. 7.3.9  Overcurrent Limiting
      10. 7.3.10 Overvoltage Protection
      11. 7.3.11 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operation near Minimum Input Voltage
      2. 7.4.2 Operation With ENA Control
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Switching Frequency
        2. 8.2.2.2 Output Voltage Setpoint
        3. 8.2.2.3 Input Capacitors
        4. 8.2.2.4 Output Filter Components
        5. 8.2.2.5 Inductor Selection
        6. 8.2.2.6 Capacitor Selection
        7.       43
        8. 8.2.2.7 Boot Capacitor
        9. 8.2.2.8 Catch Diode
        10. 8.2.2.9 Advanced Information
          1. 8.2.2.9.1 Output Voltage Limitations
          2. 8.2.2.9.2 Internal Compensation Network
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Calculations
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DDA|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.2.2.8 Catch Diode

The TPS5450 is designed to operate using an external catch diode between PH and GND. The selected diode must meet the absolute maximum ratings for the application: Reverse voltage must be higher than the maximum voltage at the PH pin, which is VINMAX + 0.5 V. Peak current must be greater than IOUTMAX plus on half the peak to peak inductor current. Forward voltage drop should be small for higher efficiencies. It is important to note that the catch diode conduction time is typically longer than the high-side FET on-time, so attention paid to diode parameters can make a marked improvement in overall efficiency. Additionally, check that the device chosen is capable of dissipating the power losses. For this design, a Diodes, Inc. B540A is chosen, with a reverse voltage of 40 V, forward current of 5 A, and a forward voltage drop of 0.5 V.