Patent ID: 7701177

Claim:
A pre-charging circuit comprising: a pre-charging path coupled between a charger and a battery for providing a pre-charging current from said charger to said battery; a pre-charging switch coupled to said pre-charging path for conducting said pre-charging current along said pre-charging path; a low-voltage pre-charging circuit coupled to said pre-charging switch for controlling said pre-charging switch, wherein said low-voltage pre-charging circuit is configured to switch on said pre-charging switch when said battery's voltage is below a first voltage level in order to provide said pre-charging current to said battery and to switch off said pre-charging switch when said battery's voltage is above said first voltage level; and a normal pre-charging circuit coupled to said pre-charging switch for controlling said pre-charging switch, wherein said normal pre-charging circuit is configured to switch on said pre-charging switch when said battery's voltage is above a second voltage level in order to provide said pre-charging current to said battery and to switch off said pre-charging switch when said battery's voltage is below said second voltage level so that said pre-charging current to said battery is cut off, wherein said first and second voltage levels are different from each other.