Wide-bandgap power devices such as those made from silicon carbide (SiC) and gallium nitride (GaN) offer superior electrical performance over conventional silicon (Si) devices for high-voltage applications. Their fast switching operation and low switching losses help increase the efficiency of power conversion circuit. This study focuses on the switching characteristics of a GaN Schottky barrier diode (SBD) and investigates the conducted noise characteristics in a DC-DC boost converter by comparing a Si PiN diode and a SiC SBD.