Patent ID: 7990669
Filing Date: 2011-08-02
Classification: H02J

Abstract:
1. A battery protection circuit for protecting a plurality of batteries connected in series, comprising: a power supply terminal connected to a positive electrode terminal of a battery at an uppermost stage among the plurality of batteries connected in series; a ground terminal connected to a negative electrode terminal of a batter at a lowermost stage among the plurality of batteries connected in series; a plurality of intermediate terminals connected to a connection point between adjacent batteries of the plurality of batteries; a plurality of monitoring circuits for monitoring voltages of the plurality of batteries relative to a reference voltage, the plurality of monitoring circuits comprising: a plurality of first wells each connected to one of the plurality of intermediate terminals; and a plurality of second wells that each surround a corresponding well of the plurality of first wells; a logical circuit configured to cause interruption of a charge/discharge path of the plurality of batteries when the voltages of the plurality of batteries are equal to or greater than the reference voltage, the logical circuit connected to an output of each monitoring circuit of the plurality of monitoring circuits; and a plurality of third wells each provided in a vicinity of a corresponding well of the first wells.