| 摘要 |
PROBLEM TO BE SOLVED: To provide a driving circuit for a semiconductor device that can suppress an increase in reverse conduction loss while preventing a semiconductor element from malfunctioning.SOLUTION: One end of a series circuit of a coil 9 and a DC power source 10 is connected to a common connection point between GaN-FETs 2 and 3 connected in series between a DC power source 1 and a ground, and the GaN-FETs 2 and 3 are so driven that one turns on and the other turns off with a dead time therebetween. A 3-voltage output circuit 8 is so configured as to output three levels of a positive voltage, a zero voltage, and a negative voltage as a driving voltage to be applied to a gate, and a coil 12 and an edge change detection circuit 6 detects change of a current flowing between a drain and a source. A control logic part 7L changes the gate voltage VgL from the positive voltage Vp to the zero voltage in turning off the GaN-FET 3 in powering, changes the voltage from the zero voltage to the negative voltage Vn thereafter based upon the change of the current, and changes the voltage from the negative voltage Vn to the positive voltage Vp on change of the current in the opposite direction from said change.SELECTED DRAWING: Figure 1 |
