| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply device that can restrain noise generated by switching from giving an impact to an input power supply voltage, and reduce an adverse effect caused by the switching to the other circuit block or the like that is operated by the input power supply voltage. SOLUTION: An input voltage is fed to a switching power supply circuit such as a switching-type DC-DC converter via a series regulator that lowers a voltage by a certain amount of the voltage. This series regulator acts as a buffer having variable resistance. The switching noise generated at the switching power supply circuit is thus attenuated by the series regulator, and switching noise in the input power supply voltage from a battery or the like is attenuated. COPYRIGHT: (C)2005,JPO&NCIPI
|
