Patent ID: 7839121

Claim:
An apparatus for managing power in a portable device, comprising: a control module configured to: determine a remaining capacity and a charging current from each of a first battery pack and a second battery pack coupled to a portable device, determine an order for charging and discharging the first and second battery packs based on the charging currents, output a battery selection signal that selects one of the first battery pack and the second battery pack based on the determined order, output a charge mode signal indicating one of a charging mode and a discharging mode based on a presence of an external voltage, and generate a charging control signal corresponding to the remaining capacity and the charging current of the selected battery pack; a charging voltage module configured to convert, based on the charging control signal, the external voltage into a charging voltage with a current capacity; and a path setting module coupled to the charging voltage module, the first and second battery packs, and a system load in the portable device, the path setting module configured to supply the charging voltage from the charging voltage module to the selected battery pack or supply output voltage from the selected battery pack to the system load according to the charge mode signal and the battery selection signal.