CONTROL/MONITOR SIGNAL TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a control/monitor signal transmission system that superposes a control signal and a monitor signal on a clock signal so as to obtain the control signal as a binary signal with a prescribed duty ratio and detects the monitor signal as a current signal. SOLUTION: A master station output section 135 changes a duty ratio for a period with a level other than a prescribed power supply voltage level and for a period with a level of the power supply voltage Vx in succession to the period above depending on respective values of control data signals so as to convent the control data signals into serial pulse voltage signals and outputs the voltage signals to a data signal line. A master station input section 139 detects the monitor data signals superimposed on the serial pulse voltage signals transmitted via the data signal line as the presence of a current signal Iis caused by the contention between the supervisory data signals and the power supply voltage Vx at a leading of the level of the power supply voltage Vx.