Patent ID: 7663267
Filing Date: 2010-02-16
Classification: H02M

Abstract:
1. A voltage controller for use in an electronic appliance using a plurality of power sources, the voltage controller comprising: a battery power source and a first path to which the battery power source is coupled; an adaptor power source and a second path to which the adaptor power source is coupled; an input power source conversion unit which includes a first transistor adapted to be turned on/off to selectively provide power from the battery power source via the first path, and wherein the second path provides power from the adaptor power source; an output voltage cutoff unit, connected to an output line of the voltage controller, for preventing the output line from outputting a power signal from either of the battery power source or the adaptor power source when an overvoltage condition is detected; a detection unit, connected to an output line of the output voltage cutoff unit, for detecting a voltage outputted from the output line of the output voltage cutoff unit; and a control unit for outputting a control signal to operate the output voltage cutoff unit to prevent the output line from outputting said voltage from either the battery power source or adaptor power source when the voltage detected by the detection unit is greater than a predetermined voltage corresponding to the overvoltage condition, wherein the output voltage cutoff unit includes a first switch connected to the control unit and a second switch having one end connected to the first switch and another end connected to the output line of the output voltage cutoff unit.