| 摘要 |
PROBLEM TO BE SOLVED: To reduce a radio wave interference caused by radiation noise from a DC-DC power supply. SOLUTION: A mobile terminal device with a power supply circuit using a DC-DC convertor includes: an externally-synchronized DC-DC convertor; an external synchronization clock source capable of changing a frequency through control by a control portion; and a function for detecting whether suppression of reception sensitivity takes place, wherein the suppression of reception sensitivity is reduced by changing the external synchronization clock of the DC-DC converter during the suppression of reception sensitivity. COPYRIGHT: (C)2010,JPO&INPIT
|
