| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a drive circuit employing a voltage-controlled element capable of reducing switching noise in response to a requirement of noise reduction and switching the element at a high speed in response to a requirement of high speed switching. <P>SOLUTION: The drive circuit 1 is provided with: MOSFETs Q1 to Q4 whose operation is controlled by a control voltage applied to their gate terminals G; a CPU 30 for outputting the control voltage; a first output circuit 21 connected to the gate terminal G of the MOSFET Q2 via a filter circuit for slowing down a rising speed of the control voltage; and a second output circuit 22 connected to the gate terminal G not via the filter circuit. When the number of engine revolutions is a prescribed number of revolutions or below, the CPU 30 outputs the control voltage to the first output circuit 21, and when the number of engine revolutions is higher than a prescribed number of revolutions, the CPU 30 outputs the control voltage to the second output circuit 22. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
