Patent ID: 7253589

Claim:
A circuit for providing a charge voltage and current to a battery, comprising: a logic control and timer circuit that is arranged to select at least one of at least two available power source voltages and provide a first and a second control voltages indicating the selection; a current/voltage control circuit that is arranged to provide one of a first error voltage and a second error voltage in response to the first and second control voltages, such that: if a first power source voltage is selected, the first error voltage controls, in part, regulation of the charge voltage and current; and if a second power source voltage is selected, the second error voltage controls, in part, regulation of the charge voltage and current; a power pass and sense circuit that is arranged to provide the charge voltage and current in response to the selected power source voltage and the corresponding error voltage, a sense determination circuit that is arranged to receive a portion of the charge voltage, to receive a reference voltage, and to provide a sense voltage; and a multiplexer that is arranged to multiplex a voltage based on at least one limit current and the portion of the charge voltage, and to provide a feedback voltage, wherein the current/voltage control circuit is arranged to receive the sense voltage, the feedback voltage, a temperature voltage, a reference voltage, and a first enable voltage and a second enable voltage; and wherein the current/voltage control circuit is further arranged to provide the first error voltage and the second error voltage to the power pass and sense circuit, wherein current/voltage control circuit is further arranged to: select a smaller of the reference voltage, the temperature voltage, and the sense voltage; combine the selected voltage with the feedback voltage; and select at least one of the at least two available power source voltages based on the first and the second enable voltages.