Phase control circuit and method of controlling power supply to heating roller.

摘要

A method and an apparatus to control power supplied to a heating roller and a phase control circuit corresponding to the method or the apparatus. The phase control circuit may include an examination unit (620) to compare levels of a sine wave having a predetermined first period and a switching signal increasing and decreasing repeatedly according to a predetermined second period, and a phase control signal generation unit (640) generating a phase control signal having a non-zero value in intervals of time from a time when levels of the switching signal and the sine wave are equal to each other until a time period when the level of the sine wave is zero.