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

Return Current Through Output Power Ground

When doing the layout, prioritize the VOUT trace, as this trace carries the highest current in the design. Make sure that enough layers are also used for the PGND return. In the current design version, there are four dedicated layers for PGND return. If necessary, to reduce board thickness or minimize PCB losses, a copper bar can be added externally on the bottom side to route the return current from the PGND output pin to the low-side LMG3100R017 PGND.

TIDA-050095 Copper Bar Placement Figure 4-2 Copper Bar Placement