Patent ID: 6472849
Filing Date: 2002-10-29
Classification: H02J

Abstract:
An apparatus for a battery charging integrated circuit (IC) that blocks reverse currents from draining a battery, comprising:a switch circuit that includes a first input that is coupled to a power signal, a second input that is coupled to a feedback signal, and an output that is arranged to provide a charging signal; a sense circuit that includes an input that is coupled to the power signal and an output that is arranged to output a sense signal relating to the charging signal through the switch circuit; a reverse blocking circuit integrated onto IC that includes a first input that is coupled to charging signal, a second input that is arranged to receive a blocking signal indicating when to activate and deactivate the reverse blocking circuit, and an output that is arranged to couple the charging signal in response to the blocking signal; a charge circuit that includes an input that is coupled to charging signal, a first output that is coupled to the second input of the switch circuit and that is arranged to provide the feedback signal, and a second output that is arranged to couple the charging signal to the battery; and a charger detect circuit that includes a first input that is coupled to a cell signal relating to a current charge level of the battery, a second input that is coupled to the sense signal, and an output arranged to provide the blocking signal.