A high frequency, isolated 1/8th brick DC-DC converter based on eGaN FET technology demonstrates the potential improvement in power density and efficiency that can be achieved by a fully optimized design. A 36V – 75V to 12V /180 W converter is characterized and compared with a comparable power MOSFET circuit. This eGaN converter is a fully regulated, phase shifted full bridge topology, with full bridge synchronous rectification test at 333kHz. The efficiency at 333kHz is compared to equivalent MOSFET product at 250kHz. From these results it is clear that even a non-optimized design is capable of outperforming leading MOSFET design by delivering up to 14 A compared to 12A with the same total power loss. That’s a 16% increase in power output.