| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a power supply device capable of suppressing heat generation of a charging control circuit charging a battery incorporated in a small electronic appliance such as a cellphone. <P>SOLUTION: When charging the battery 4 incorporated in the cellphone, an AC adapter 1 that is a DC power supply having a high set output voltage is connected. A voltage difference between input and output of the charging control circuit 2 by a voltage drop type regulator is detected, and the output voltage of the AC adapter is descent-controlled on the basis of a control signal by a detected voltage thereof. The voltage difference between the input and output of the charging control circuit becomes minimum, and an output voltage of the charging control circuit becomes a battery charging voltage. Electric power consumed during battery charging of the charging control circuit becomes minimum to reduce the heat generation. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
