| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a power supply circuit capable of reducing an occupied area of an output stage circuit of the power supply circuit and easily blocking a reverse directional current from a capacitor connected in parallel with a load and to provide a mobile electronic apparatus. <P>SOLUTION: The power supply circuit is provided with: a second MOS transistor inserted between a back gate and a source of a first MOS transistor; a third MOS transistor inserted between the back gate and a drain of the first MOS transistor; and a control circuit for turning ON/OFF the second and third transistors that compares voltage of power received from a DC power supply with voltage at an output terminal, connects the back gate to either of the source and the drain in a manner of reverse-biasing a parasitic diode of the first MOS transistor via the back gate when the voltage of the power is lower than the voltage at the output terminal, or connects the back gate to the other of the source and the drain when the voltage of the power is equal to or higher than the voltage at the output terminal. <P>COPYRIGHT: (C)2004,JPO</p> |
