| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve a problem that a conventional power supply control circuit increases in current consumption in a standby mode wherein an electric power source is connected normally. <P>SOLUTION: A power supply control circuit includes an output transistor T1 and a load 11 connected between a power supply terminal PWR and a ground terminal GND, a protective transistor MN8 connected between the gate of the output transistor T1 and the ground terminal GND, and bringing the output transistor T1 into a conduction state when the polarity of an electric power source 11 is inverted, a negative voltage control portion which brings the output transistor T1 into a conduction state when a counter electromotive voltage is applied to an output terminal, a compensation transistor MN7 bringing the ground terminal GND and the output terminal into a conduction state when the counter electromotive voltage is applied to the output terminal, and a back gate control circuit 18 which controls the ground terminal GND and compensation transistor MN7, and the back gate of the protective transistor MN9 into a conduction state when the polarity of the electric power source 10 is normal. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
