A power management device for enabling multiply power sources to supply power to a load. The power management device includes a plurality of switches and a control logic. The plurality of switches are coupled to a plurality of power sources respectively and each switch coupled to each power source. The control logic is capable of selecting a set of switches among the plurality of switches to cooperate in a time-divided fashion to allow the power sources to provide power to the load. The set of switches is selected based on an electrical requirement of the load and an electrical condition of each switch.