| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a highly reliable piezoelectric inverter circuit capable of protecting a switching element, a piezoelectric transformer and an output connector when an excessive current occurs due to a large variation in load state. <P>SOLUTION: The piezoelectric inverter circuit includes: a piezoelectric transformer 6; a drive circuit 15; a load 8; a current detecting circuit 9 for detecting a load current; and a control circuit 3 having functions of inputting information about the load current, controlling a voltage or a frequency outputted from the drive circuit 15 and controlling so that the load current may be constant. The piezoelectric inverter circuit has a latch circuit 10 for detecting the maximum value of the load current and holding an ON state of an output signal which turns ON when the maximum value becomes a predetermined set value or more. An output signal of the latch circuit 10 is inputted into the control circuit 3, and the control circuit 3 stops the driving of the piezoelectric transformer when the output signal is in an ON state. <P>COPYRIGHT: (C)2009,JPO&INPIT |
