| 摘要 |
PROBLEM TO BE SOLVED: To detect the abnormal output for the PWM output control and to decide an ON/OFF failure by deciding the coincident or non-coincident state between a PWM control pulse signal and a drive signal through the comparison of them. SOLUTION: An output part 5 outputs the PWM control pulse signal supplied from a timer circuit 4 to a drive circuit 10 of a controlled device 2 and also holds the level state of the pulse signal to supply this holding contents to a comparison device 8. The circuit 10 produces a drive signal that has its state change in response to the PWM control pulse signal and then drives a load device 11 that is prepared at the final stage such as a flow rate control valve, a motor, and a light source. Meanwhile, an input part 7 holds the state of the drive signal detected by a detection circuit 6 and supplies it to the device 8. The device 8 compares the state of a PWM controller that is supplied from the part 5 with the state of the drive signal that is supplied from the part 7 and stores this comparison result in a storage 9. |
