A control circuit of a digital control power circuit is provided. The control circuit includes a feedback controller configured to generate a digital duty command value such that a digital feedback value corresponding to an output voltage of the digital control power circuit is close to a target value thereof, a pulse generator configured to generate a pulse signal having a duty ratio corresponding to the digital duty command value, a non-linear controller configured to correct a pulse width of the pulse signal when a variation in the output voltage is detected, and a driver configured to drive a switching device of the digital control power circuit depending on the pulse signal.