| 摘要 |
PROBLEM TO BE SOLVED: To provide means which performs ON/OFF control at an exact timing while suppressing disorder in the timing of a zero-cross signal.SOLUTION: A power control device includes: a heater; switching means including a transistor; drive means for driving the heater with the switching means; zero-cross detection means which detects zero-cross of a commercial AC power source and outputs a zero-cross detection signal; phase synchronizing means which outputs a phase synchronizing signal synchronized with the zero-cross detection signal on the basis of a multiplication pulse; and signal output means which demultiplexes the phase synchronizing signal and outputs a PWM signal to the drive means. The phase synchronizing means outputs the phase synchronizing signal for which the multiplication pulse and the zero-cross detection signal are phase-synchronized. The signal output means supplies the PWM signal to the drive means in accordance with a PWM signal that is demultiplexed into the same frequency as the phase synchronizing signal, and controls a conduction phase angle to the heater.SELECTED DRAWING: Figure 1 |
