Benchmarking of a Novel SiGe Diode Technology for the Usage in High Frequency 48 V/ 12 V Converter Applications

The recent utilization of increased switching frequencies in power electronics due to the availability of wide bandgap devices has significantly been affecting automotive 48 V = 12 V converter designs. In this paper a comprehensive performance comparison of a novel 120 V = 3 A silicon-germanium (SiGe) based diode with special regard to the suitability for such high frequency converters is presented. For this purpose, a low inductive double-pulse test bench operated by a 100 V e-mode GaN-HEMT with very high di/dt transients up to 1 A/ns was designed. The considered main criteria are the conduction, blocking and switching characteristics. The new SiGe diode is compared to four other diodes which are specified for a comparable operation range and have equal packaging but hold different layer structures, namely Trench Schottky, Planar Schottky and pn diodes. It is revealed that the performance of the diodes can significantly differ from expectations derived from the datasheet in the presence of high speed switching.