Silicon carbide (SiC) is an expected candidate as a material for the next generation power semiconductor devices. In this paper, the authors evaluate the power device loss of a DC-DC buck converter, where the silicon (Si) free wheeling diode is replaced with an SiC schottky barrier diode (SBD). The loss reduction of the DC-DC buck converter is discussed with respect to switching frequency and duty ratio of the gate drive signal. © 2010 IEEE.