An embodiment of a charger may include an input, at least one switch having a first node coupled to a reference voltage, a current sensor coupled between the input and a second node of the at least one switch, an output coupled to a third node of the at least one switch, and a charge controller coupled to the input to determine an input voltage, to the current sensor to determine an input current and to control inputs of the at least one switch. The at least one switch may be responsive to control signals supplied by the charge controller to the control inputs thereof to control voltage and current at the output of the charger. The charge controller may be responsive to the input voltage and the input current to produce the control signals in a manner that maximizes electrical power drawn at the input.