| 摘要 |
<p>PROBLEM TO BE SOLVED: To charge a battery built in a portable electronic apparatus even when the power is turned off by a constitution wherein a CPU turns a quick charging means on and turns a slow charging means off when the charging operation is not finished whereas turns the quick charging means off and turns the slow charging means on upon finishing the charging operation. SOLUTION: A power supply detection circuit 6 detects the connection of a charger 2 for portable electronic apparatus based on the output voltage at a power supply terminal 15 thus detecting on/off of a power switch 5. If the power switch 5 is turned off when a battery 4 is being charged, a current is fed directly from the battery 4 to a CPU 13 which then detects the charged state based on the output voltage from the battery 4. If the charged state represents an unfinished charging operation, a quick charging circuit in a charging circuit 3 is turned on and a slow charging circuit is turned off. If the charged state represents a finished charging operation, the quick charging circuit is turned off and the slow charging circuit is turned off. Consequently, the battery 4 can be charged even when the power of portable electronic apparatus 1 is turned off.</p> |
