| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a circuit for driving a semiconductor switching element which can switch at a high speed a switching element having a limitation on the application of driving voltage while ensuring isolation. <P>SOLUTION: FET_Sg1,Sg2 are inserted in opposite directions in a current path 5, including an FET 1, on a secondary winding N2 of a transformer Tr constituting a drive circuit 2, and an AC current generated by an H bridge circuit 4 is supplied to a primary winding of the transformer. FET_Sg1 turns on when an AC voltage V_N2 becomes one polarity and a voltage applied to a gate thereof exceeds a threshold, to apply a charge current to a gate of the FET 1 and turn it on. FET_Sg2 turns on when the AC voltage V_N2 becomes the other polarity and a voltage applied to a gate thereof exceeds the threshold, to draw a discharge current from the FET 1 and turn it off. <P>COPYRIGHT: (C)2012,JPO&INPIT |
