Patent ID: 7733060
Filing Date: 2010-06-08
Classification: H02J

Abstract:
1. A charging IC used for charging a rechargeable battery built into an electronic device, comprising: a power source unit that can be fed with power from an external power source with a drooping characteristic to pick up a constant current; and a control unit that controls a first operation and a first current of the power source unit and controls a second operation and a second current of an active element disposed on a charging path of the rechargeable battery, wherein the control unit applies a first constant current from the external power source to the rechargeable battery through the active element by halting the operation of the power source unit and constant-current controlling the active element, and the control unit applies a second constant current smaller than the first constant current from the power source unit to the rechargeable battery without passing through the active element by halting the operation of the active element and controlling the power source unit, after the rechargeable battery is charged with the first constant current to a predetermined voltage.