Patent ID: 7629833

Claim:
A power supply apparatus of a semiconductor integrated circuit, the apparatus comprising: a power controller that detects a level of power supplied from outside to output a control signal as information on the level detected; and a power supply that controls an internal resistance component in response to the control signal, controls the level of the power supplied from the outside using the control signal, and supplies the power supplied from the outside having the level controlled to circuit blocks, wherein the power controller includes: a clock generating unit that receives an external clock and generates a sampling clock and a trigger clock; a reference voltage generating unit that generates reference power; a digital converting unit that receives the sampling clock and converts information on a level change of the power supplied from the outside with respect to the reference power into a detection signal having a plurality of bits; and a control signal generating unit that receives the sampling clock and the trigger clock and generates the control signal having the plurality of bits from the detection signal having a plurality of bits.