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

7.1 Overview

The TPS5450 device is a 36-V, 5-A, step-down (buck) regulator with an integrated high-side n-channel MOSFET. The device implements constant-frequency voltage-mode control with voltage feed forward for improved line regulation and line transient response. Internal compensation reduces design complexity and external component count.

The integrated 110-mΩ high-side MOSFET supports high-efficiency power-supply designs capable of delivering 5-A of continuous current to a load. The gate-drive bias voltage for the integrated high-side MOSFET is supplied by a bootstrap capacitor connected from the BOOT to PH pins. The TPS5450 device reduces the external component count by integrating the bootstrap recharge diode.

The TPS5450 device has a default input start-up voltage of 5.3 V typical. The ENA pin can be used to disable the TPS5450 reducing the supply current to 18 µA. An internal pullup current source enables operation when the EN pin is floating. The TPS5450 includes an internal slow-start circuit that slows the output rise time during start-up to reduce in rush current and output voltage overshoot.

The minimum output voltage is the internal 1.221-V feedback reference. Output overvoltage transients are minimized by an Overvoltage Protection (OVP) comparator. When the OVP comparator is activated, the high-side MOSFET is turned off and remains off until the output voltage is less than 112.5% of the desired output voltage.

Internal cycle-by-cycle overcurrent protection limits the peak current in the integrated high-side MOSFET. For continuous overcurrent fault conditions the TPS5450 will enter hiccup mode overcurrent limiting. Thermal protection protects the device from overheating.