| abstract |
A hybrid switching circuit (12a, 12d) includes first (Q5,Q6) and second (Ql, Q4) switching devices containing first and second unequal bandgap semiconductor materials. These switching devices, which support parallel conduction in response to first and second control signals, are three or more terminal switching devices of different type. For example, the first switching device may be a three or more terminal wide bandgap switching device selected from a group consisting of JFETs, IGFETs and high electron mobility transistors HEMTs, and the second switching device may be a Si-IGBT. A control circuit is also provided, which is configured to drive the first and second switching devices with first and second periodic control signals having first and second unequal duty cycles. The first duty cycle may be greater than the second duty cycle and the active phases of the second periodic control signal may occur exclusively within the active phases of the first periodic control signal. |