Patent ID: 9035599
Filing Date: 2015-05-19
Classification: H02J

Abstract:
1. A charge control circuit of a charge circuit configured to convert electric power supplied from an input power supply into electric power for charging a secondary battery, and output the electric power for charging the secondary battery, the charge control circuit comprising: a first comparator circuit configured to compare a voltage of the secondary battery with a first comparison voltage corresponding to a voltage of the input power supply; a first transistor connected to the input power supply, the first transistor configured to supply an input current to an inductor of a boost DC-DC converter; a first control circuit configured to control the first transistor; and a second control circuit configured to control a second transistor configured to increase an inductor current flowing through the inductor and a third transistor configured to decrease the inductor current so that the boost DC-DC converter performs a boost operation, the first control circuit configured to turn on the first transistor, and the second control circuit configured to perform switching of the second transistor and the third transistor in a complementary manner, and cause the boost DC-DC converter to perform the boost operation, when the voltage of the secondary battery is equal to or higher than the first comparison voltage; and the first control circuit configured to control the first transistor so that the input current takes a predetermined value, and the second control circuit configured to turn off the second transistor and turn on the third transistor, when the voltage of the secondary battery is lower than the first comparison voltage.