TIDT257A February   2022  – October 2022

 

  1.   Description
  2.   Features
  3.   Application
  4. 1Test Prerequisites
    1. 1.1 Voltage and Current Requirements
    2. 1.2 Considerations
    3. 1.3 Dimensions
  5. 2Testing and Results
    1. 2.1 Efficiency Graphs
    2. 2.2 Efficiency Data
      1. 2.2.1 THD Optimization
    3. 2.3 Thermal Images
      1. 2.3.1 Low-Side GaN Junction Temperature
    4. 2.4 Thermal Mechanical Design
      1. 2.4.1 Design Parameters
      2. 2.4.2 Thermal Resistance Calculation
      3. 2.4.3 Heat-Sink Diagrams
    5. 2.5 EMI
  6. 3Waveforms
    1. 3.1 AC Drop
    2. 3.2 Load Transients
    3. 3.3 Start-Up Sequence

Description

This reference design is a GaN based 3-kW single-phase continuous conduction mode (CCM) totem-pole power factor correction (PFC) converter targeting maximum power density. The supply is designed to support a maximum input current of 16-ARMS and peak power of 3.6 kW. The power stage is followed by a baby boost converter, which helps to greatly reduce the size of the bulk capacitor. The LMG3522 top-side cooled GaN device with integrated driver and protection, enables higher efficiency and reduces power supply size and complexity. The F28004x or F28002x C2000 controller is used for all the advanced controls including fast relay control, baby boost operation during AC drop out event, reverse current flow protection, and communication between the PFC and house-keeping controller. The PFC operates at a switching frequency of 65 kHz and achieves peak efficiency of 98.7%.