| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply circuit that consists of a plurality of transforming circuits to generate voltages of different values from a common power source and that avoids the effect of a rush current while maintaining the operability of an electronic apparatus. SOLUTION: The power supply circuit 10 of a digital camera includes a power supply circuit 20 for imaging devices, a power supply circuit 50 for driving a motor, and a power supply circuit 60 for microcomputers. The power supply circuit 20 is intermittently started during the operation of the digital camera by a boosting circuit provided with a transformer 36. When the power supply circuit 20 is started, the power supply circuit 50 immediately supplies electric power to a first switching regulator 28 via a third diode 43, which makes the collector current of a first transistor 44 smaller so that the rush current that flows in a smoothing capacitor 34 is inhibited. Furthermore, a resistor 32 makes the amount of the rush current small and thereby inhibits the drop of the terminal voltage of a DC power supply 12 when the primary side voltage of the transformer 36 drops. COPYRIGHT: (C)2005,JPO&NCIPI
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