The paper presents device characteristics of a recent developed 1.2 kV silicon carbide (SiC) switching cell and system performance of an interleaved boost converter using that switching cell. The static and dynamic characteristics of the full SiC switching cell, including a SiC MOSFET and a SiC diode, are experimentally extracted and the advantages of the devices are evaluated. A 2.5 kW interleaved boost converter for PV applications is implemented as benchmark test system. It is used to evaluate the system efficiency improvement by using the full SiC switching cell. The experimental results show that the SiC MOSFET greatly improves the efficiency of the converter in contrast to Si 1.2kV IGBT devices.