US Patent 7638971 Multiple device battery charger

An improved method of charging multiple batteries and battery powered devices of different types at one time. Utilizing multiple methods of supplying DC power to external batteries, a user can charge a variety of devices at the same time. The power is routed in three distinct ways: directly to the output ports, through resistors, and through a switch converter. Then, using methods established and known to one in the art, external electronic devices may be attached to the output ports. Thus, the external battery will be charged through whichever route delivers the proper voltage. This design utilizes the logic contained within the external device for charging purposes.