TIDUFF4 October   2025

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
      1. 1.1.1 General TI High Voltage Evaluation User Safety Guidelines
        1. 1.1.1.1 Safety and Precautions
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 GaN Power Stage
      2. 2.2.2 Inductor
      3. 2.2.3 Controller
      4. 2.2.4 Cooling
        1. 2.2.4.1 Heat Sink Placement
        2. 2.2.4.2 Via Placement
        3. 2.2.4.3 Copper Block
    3. 2.3 Highlighted Products
      1. 2.3.1 LMG3100R017
      2. 2.3.2 UCD3138A
      3. 2.3.3 TPSM365R6V5
      4. 2.3.4 TMP61
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Software Requirements
    3. 3.3 Test Setup
    4. 3.4 Test Results
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
      3. 4.1.3 PCB Layout Recommendations
        1. 4.1.3.1 Power Loop Optimization
        2. 4.1.3.2 Return Current Through Output Power Ground
    2. 4.2 Tools and Software
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5. 4.5 Trademarks
  11. 5About the Author

1 System Description

Server power requirements increase with the proliferation of AI and increased data processing loads. The architecture shifts to a higher voltage for distribution, 48V, from 12V, to reduce I²R losses. This shift requires conversion of the 48V–12V levels on the motherboard to power the main controller multiphase power stage and peripherals, such as PCIe and HDD.

The buck converters are not efficient enough to achieve 98%+ peak efficiency due to hard-switching. However, TI GaN integrated power stages enable efficient 48V–12V conversion with a 2kW power output using a four-phase buck topology.