An Experimental Performance Comparison of GaN and Silicon Based FETs in an Emergency LED Driver

Gallium Nitride (G<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$a$</tex>N) High-Electron-Mobility Transistors (HEMTs) are currently prominent in the power electronics literature due to the increasing viability of use across all industries. However, there are still gaps in the GaN related literature due to the vast coverage of power electronics. One such gap is in understanding the efficiency benefit of GaN devices compared to Silicon in an Emergency LED Driver application. In addition, the on resistance and parasitic capacitances of the GaN device play important roles in selecting the optimal device for the converter. This paper presents experimental results of a direct swap of various Schottky Gate E Mode GaN devices compared to an NMOS Silicon device for a Low Power, Zero Voltage Switching (ZVS), Boundary Conduction Mode (BCM) Emergency LED driver converter, addressing the gap in literature. A 20 percent efficiency boost over silicon is observed in the megahertz region, using a Schottky diode antiparallel to the FET.