Monolithic Bidirectional Lateral GaN Switches Reinvigorate Power Electronics Applications

Monolithic bidirectional (BD) voltage/current lateral GaN switches are becoming commercially available, leveraging the ”silicon” economies of scale established by the mature lateral power GaN infrastructure. Key features of major alternative BD device architectures are reviewed. In particular, monolithic BD switches with a dual-gate structure are advantageous since they have a common drain region that reduces cell-pitch and on-state resistance Ron, and only increase switch area by about 1.2X compared to similarly rated commercial GaN unidirectional voltage blocking devices. There are many types of power electronics applications that benefit very directly and, in some cases, dramatically from the commercial availability of monolithic BD switches. Four promising candidate applications are briefly discussed including matrix converters, current-source inverters, T-Type multi-level voltage-source inverters, and solid-state circuit breakers. The article closes with an acknowledgment of the practical obstacles to the commercial production of monolithic BD switches and reasons for optimism that these obstacles will be overcome.