| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an overvoltage protecting circuit for protecting a load from overvoltage without stopping power supply even if overvoltage occurs between DC power supply lines while an increase of a circuit area is suppressed. <P>SOLUTION: A voltage control circuit 20 switches a transistor M11 in accordance with a terminal voltage VC of a capacitor C11, which rises with a rise of power voltage VB, when a power voltage VB between a power supply line 17 and a ground line 18 exceeds a target line and rises, and repeats charging/discharging of the capacitor C11. A voltage value of the terminal voltage VC is limited to a voltage value between an upper limit value and a lower limit value of protection setting voltage. <P>COPYRIGHT: (C)2009,JPO&INPIT |
