Patent ID: 6804098
Filing Date: 2004-10-12
Classification: H02J

Abstract:
A charge/discharge protection circuit for a rechargeable battery, secured by a fuse, comprising a control circuit, which opens or closes a load switch, dependent on the magnitude of the voltage on the battery terminals, the voltage on the charge/discharge terminals of said protection circuit and on the magnitude of the charge/discharge current, thus characterized that a number of partial switches is located parallel to the load switch, that an overvoltage detector closes, in case of an overvoltage on charge/discharge terminals, all partial switches via a control logic, which afterwards cyclically progressing opens one partial switch after the other, that a voltage detector, monitoring the remaining voltage over the partial switches inhibits the opening of at that time next partial switch if the remaining voltage over the still closed partial switches is higher than a predefined limit of said remaining voltage, and that the control logic activates a permanent disconnection of the battery from the charge/discharge terminals if the cycle is not completed within a predefined time Interval, that means, if at least the last partial switch is still closed.