| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device constituted so that a high-voltage power source is protected when the runaway of a controller controlling the high-voltage power source is caused. SOLUTION: This device is constituted of a watchdog timer 10 counting the output time of a signal outputted by a CPU, an IC1 12 monitoring the above mentioned signal and outputting a RESET signal when the output time of the signal becomes over a restriction time set to the timer 10, an IC2 13 to which the RESET signal is inputted and from which the auxiliary signal of a PWM signal is outputted and an AND circuit 14 to which the PWM signal and the auxiliary signal are inputted and from which they are outputted to the high- voltage power source. When the runaway of the CPU is caused by noise and the like, the high-voltage power source is prevented from being broken because an excessive current flows in the power source by detecting the runaway of the CPU and outputting the RESET signal by the IC1 12 and outputting a signal obtained by combining the auxiliary signal and the PWM signal from the IC2 13 to which the RESET signal is inputted to the high-voltage power source. |
