A Novel Cascode GaN Switch Integrating Paralleled GaN DHEMTs for High-Power Applications

摘要

At present, existing GaN HEMTs are only available in low current ratings. To meet the desire for higher power applications, this paper proposes a novel cascode GaN switch integrating a Si-MOSFET and several paralleled d-mode GaN HEMTs. The proposed switch can withstand twice or more the current than original cascode GaN HEMT while using only one Si-MOSFET with one gate driver required, increasing the power density, improving the system efficiency and saving the cost. Moreover, the paper discusses the causes of possible unbalanced current sharing between paralleled GaN DHEMTs and analyzes the mechanism of potential loop current and current oscillation in detail. A group of simulation results validate the viability of proposed new cascode GaN switch and verifies the relative analysis on parallel operation.