Patent ID: 7260013

Claim:
A power supply device comprising: a power control unit for generating a power control signal so as to control an output power of the power supply device in response to an operation mode of an external device; a power generation unit for generating a first power level or a second power level that is less than the first power level, in response to the power control signal, to provide power to the external device, wherein the first power level at a higher power level than the second power level is provided to the external device for a predetermined time before the external device enters a first mode of operation that requires the first power level at the higher power level than the second power level; an internal clock generation unit for generating an internal clock signal having a regular period during an operation section of the external device including the first mode of operation and a second mode of operation; a counter unit for generating first, second, third and fourth clock signals in response to the internal clock signal; and a mode control unit for generating a mode signal for partitioning the operation section into the first mode and the second mode in response to the fourth clock signal, wherein the power control unit generates the power control signal in response to the internal clock signal, the first, second, and third clock signals and the mode signal.