TIDUBE1D January   2016  – August 2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Highlighted Products and Key Advantages
      1. 2.2.1 UCC28180 – PFC Controller
      2. 2.2.2 UCC27524 – Dual Low-Side Gate Driver
      3. 2.2.3 UCC28881 – 700-V Off-Line Converter
    3. 2.3 System Design Theory
      1. 2.3.1 Selecting Switching Frequency
      2. 2.3.2 Calculating Output Capacitance
      3. 2.3.3 Calculating PFC Choke Inductor
      4. 2.3.4 Selecting Switching Element
      5. 2.3.5 Boost Follower Control Circuit
      6. 2.3.6 Bias Power
      7. 2.3.7 On-Off Switch
      8. 2.3.8 Thermal Design
  9. 3Hardware, Testing Requirements, and Test Results
    1. 3.1 Required Hardware
      1. 3.1.1 Test Conditions
      2. 3.1.2 Recommended Equipment
      3. 3.1.3 Procedure
    2. 3.2 Test Results
      1. 3.2.1 Performance Data
        1. 3.2.1.1 Efficiency and iTHD
        2. 3.2.1.2 Standby Power and Output Voltage
      2. 3.2.2 Performance Curves
        1. 3.2.2.1 Efficiency Curve
        2. 3.2.2.2 Voltage Follower Performance
      3. 3.2.3 Functional Waveforms
        1. 3.2.3.1 Power On Sequence
        2. 3.2.3.2 Inrush Current Protection
        3. 3.2.3.3 Switching Node
        4. 3.2.3.4 Waveform Under 3.5kW, 230VAC
      4. 3.2.4 Thermal Measurements
  10. 4Design Files
    1. 4.1 Schematics
    2. 4.2 Bill of Materials
  11. 5Documentation Support
  12. 6Trademarks
  13. 7About the Author
  14. 8Revision History

3.2.4 Thermal Measurements

To better understand the temperature of power components and maximum possible operating temperature, the thermal images were plotted at room temperature (25°C) with a closed enclosure, no airflow, and at full-load conditions. The board was allowed to run for 30 minutes before capturing a thermal image, and heatsink is cooled down with forced air flow provided by two 27CFM, 24 VDC, 2.64W Cooling fans from two sides of heatsink.

Figure 3-9 shows the temperature of power components at input voltage of 230-V AC with the 3.5-kW power output.

TIDA-00779 Top-Side Temperatures at 230-V AC Input and 3.5-kW Output Figure 3-9 Top-Side Temperatures at 230-V AC Input and 3.5-kW Output