| 摘要 |
PROBLEM TO BE SOLVED: To reduce the power consumption by equipping a charging circuit with a constant current circuit which supplies the minimum charge current to compensate the action of CPU and a first current path which supplies a large current, with its conductivity controlled when a secondary battery is charged to specified voltage. SOLUTION: A changing 10 supplies a minimum constant current required to enable the action of CPU 20 immediately after start of charge. Next, at the point of time when the charging voltage goes up to the voltage by which the dive of the CPU 20 becomes possible, the CPU 20 controls the charge current 10 so as to increase the supply current to the secondary battery 1. Accordingly, it follows that a great charging current does not flow to the secondary battery 1 until the CPU 20 drives it, even if it is supplied with DC power 11. Hereby, in case that there is fault in the secondary battery 1, the charging circuit 10 can prevent the accident caused by overcurrents and drop the power consumption. |
