BATTERY CHARGING SYSTEM AND A METHOD THEREOF

A battery charging and balancing circuit, for charging a battery pack having a plurality of cells. The battery charging and balancing circuit having a detecting circuit to provide a balancing connection indicating signal; a charging circuit to charge the battery pack based on the cell voltages when the balancing connection indicating signal is valid, and to charge the battery voltage otherwise; and a balancing circuit to control the discharging switches coupled with the cells based on the cell voltages when the balancing connection indicating signal is valid.