An Efficiency Comparative Workbench Study of eGaN and Silicon Discrete Transistor based Buck Converters

This paper presents a comparative efficiency experimental study of eGaN and conventional Si MOSFET power transistors within similar power ratings. The aim is to prove that the use of eGaN-FET power devices can be beneficial for 12V/1.2V POL buck converters required for microprocessors, FPGA, and other such power supply- demand architectures. Two evaluation boards (a Silicon MOSFET based one and an eGaN FET based one) are tested from an efficiency point of view on the work-bench; for a higher precision, the output current delivered in load was measured by mean of a current probe, avoiding in this way the adding extra resistance in series with the load which has very small values. Because the temperature highly impacts the efficiency performance and reliability of converters within power supplies, making the environment a critical factor in their selection, a thermal scanning of the power devices' package was taken in order to show how is the heat dissipated and giving a suggestive picture of converter's reliability.