| 摘要 |
<P>PROBLEM TO BE SOLVED: To increase the degree of freedom in designing a drive circuit of a switching element. <P>SOLUTION: An AC inverter 1 comprises switching elements SW1-SW4, an H bridge circuit 2 having an output section 3, a driver 4, and an overcurrent detector 6. The driver 4 comprises drive circuits D1 and D1 connected respectively with the control terminal of the switching elements SW1 and SW2, drive circuits D2 and D3 connected respectively in parallel with the control terminal of the switching elements SW3 and SW4, and a control circuit 5 connected with the drive circuits D1, D2 and D3. The control circuit 5 switches the driving mode of the switching elements SW3 and SW4 depending on the control frequency. The drive circuit D2 having a resistor of large resistance is selected in a normal mode in order to suppress radiation noise, and the drive circuit D3 having a resistor of small resistance is selected in a current limit mode in order to suppress heat generation. <P>COPYRIGHT: (C)2004,JPO |
