摘要 |
PURPOSE:To avoid the hunting of a control system for the feedback of the flow rate, etc., by producing a pulse having a duration proportional to the deviation between the target value and the measured value of the quantity to be controlled. CONSTITUTION:An inverter 15 inverts the output of a 1-shot circuit 14. An AND circuit 16 obtains an AND of the outputs of the inverter 15 and a converting circuit 13. An inverter 17 inverts the output of the circuit 16. A 1-shot circuit 18 has a rise along with the rise of the output pulse of the inverter 17 and then produces a pulse which has a fall after a prescribed period of time. In case when the size of a deviation signal supplied to a terminal 11 is smaller than the size corresponding to the pulse duration of the circuit 14, no pulse emerges at a terminal 20. While a pulse having a duration proportional to the size of the deviation signal emerges when the size of the deviation signal is larger than the pulse duration of the circuit 14. |