Patent ID: 8890909

Claim:
A power control device which generates a PWM signal according to an obtained voltage signal and performs PWM control of electric power supplied to a load, the power control device comprising: a sampling section which performs sampling on the voltage signal; a duty factor updating section which updates a duty factor of the PWM signal according to a result of the sampling; and a masking period updating section which updates a masking period by switching the masking period between on and off periods of the PWM signal; wherein the sampling section inhibits the sampling from being performed in the masking period which has been switched and set to be one of the on and off periods of the PWM signal; when the duty factor is higher than a predetermined threshold value, the masking period updating section updates the masking period by setting the masking period to be the off period; and when the duty factor is lower than the predetermined threshold value, the masking period updating section updates the masking period by setting the masking period to be the on period.