SNOU215 January   2025

 

  1.   1
  2.   Description
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
    1. 1.1 System Block Diagram
    2. 1.2 Kit Contents
    3. 1.3 Voltage and Current Requirements
    4. 1.4 Design Consideration
      1. 1.4.1 Boost Inductor Design
      2. 1.4.2 High Frequency Power Switch Selection
      3. 1.4.3 Input AC Voltage Sensing
      4. 1.4.4 Bulk Voltage Sensing
      5. 1.4.5 Input Current Sensing
      6. 1.4.6 Baby Boost Design
      7. 1.4.7 Relay
      8. 1.4.8 Protection
        1. 1.4.8.1 Over Voltage Protection
        2. 1.4.8.2 Over Current Protection
  7. 2Software
    1. 2.1 Quickstart guide
    2. 2.2 Download Firmware
  8. 3Power Up
    1. 3.1 Required Equipment
    2. 3.2 Considerations
    3. 3.3 Start-Up Sequence
  9. 4Implementation Results
    1. 4.1 Start-Up Waveform
    2. 4.2 THD Performance
    3. 4.3 Power Factor
    4. 4.4 Efficiency Graph
    5. 4.5 E-meter Performance
    6. 4.6 Load Transients
    7. 4.7 Input Current Waveforms
    8. 4.8 AC Drop Test
    9. 4.9 Thermal Images
  10. 5Hardware Design Files
    1. 5.1 Design Files
  11. 6Related Documentation
    1. 6.1 Supplemental Content
  12. 7External Reference

Description

This reference design is a Gallium nitride (GaN) based, 3.6kW, single-phase, continuous conduction mode (CCM) totem-pole bridgeless power factor correction (PFC) converter targeting M-CRPS server power supply. This design includes E-meter functionality with 0.5% accuracy using AMCx306 as current sensing device, eliminating the need for external power metering ICs. An alternative low cost current sensing option using TMCS1133 is also provided in this design. The supply is designed to support a maximum input current of 16-ARMS and peak power of 3.6kW. The power stage is followed by a baby boost converter, which helps to greatly reduce the size of the bulk capacitor. This design works with TI GaN half bridge daughter cards (E.g. LMG3522EVM-042, LMG3422EVM-043, LMG3650EVM-113). LMG3522R030, LMG3422R030, LMG3650R025 are TI 25-30mΩ high-voltage GaN FET with integrated driver and protections, enable high efficiency and high power density. The F28003x C2000™ real-time microcontroller is used for all the advanced controls including re-rush current limit, baby boost operation during AC drop out event, e-metering, and communication between PFC and house-keeping controller. In addition, the F28003x microcontroller has built-in Sigma-Delta filter module to interface with AMC1306 precision current sensing reinforced isolated modulator to achieve industry leading low total harmonic distortion (iTHD) and high measurement accuracy. The PFC operates at a switching frequency of 65kHz and achieves peak efficiency of 98.93%.