| 摘要 |
PROBLEM TO BE SOLVED: To provide a battery charge circuit, which can avoid the application of voltage over the rated value to a battery, when the voltage of the battery is in the vicinity of full charge voltage, portable electronic equipment, and a semiconductor integrated circuit. SOLUTION: This battery charge circuit 1, which is used being connected with a DC power source 2, is equipped with a control transistor Tr1 which is provided in a charge path between the DC power source 2 and a battery 3 and controls the DC voltage from the DC power source 2 and outputs it as charge voltage Vchg, a counter-flow preventive transistor Tr2, which is provided in the charge path and outputs charge voltage Vchg to the battery 3 and also is switched off, when a current has flown back to the DC power source 2 from the battery 3, and a charge control circuit 11, which makes the counter-flow transistor Tr2 conductive at start of charge to the battery 3 and makes the control transistor Tr1 conductive, after the passage of a certain time since the start of charge. COPYRIGHT: (C)2008,JPO&INPIT
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