Patent ID: 7547994

Claim:
An apparatus for managing power of a mobile terminal, comprising: a first voltage regulating unit that changes the level of power from an external power source to a first level; a second voltage regulating unit that changes the level of power from the first voltage regulating unit or the external power source to a second level; a comparing unit that compares an output of the second voltage regulating unit to a pre-set reference voltage; a switching unit that switches an output of the external power source or the first voltage regulating unit to the second voltage regulating unit; and a controller that controls the switching of the switching unit according to the comparison result from the comparing unit, wherein the output level of the first voltage regulating unit and the output level of the second voltage regulating unit are within a certain range, wherein the controller controls the switching unit to immediately switch to disconnect the output of the first voltage regulating unit from the second voltage regulating unit and to connect the output of the external power source to the second voltage regulating unit when the output of the second voltage regulating unit is greater than a voltage equal to the pre-set reference voltage plus a pre-set tolerance value or less than a voltage equal to the pre-set reference voltage minus the pre-set tolerance value.