| 摘要 |
PURPOSE:To obtain a relay driving signal generating circuit which operates stably, by equipping a FF which is set by a pulse signal of any width and a timer which resets the FF after set time from the point in time when the FF is set. CONSTITUTION:A relay operating signal is detected by rise detection circuit 37 to set signal FF38 of narrow pulse width. Once FF38 is set, timer 40 is made to operate by signal G. Timer 40 attains timer operation by a clock signal obtained through dividing12 of a power-supply frequency, and then sends out signal I resetting FF38 when preset time elapses. Then, FF38 is reset by signal I and drives driver 30. Driver 30 turns ON only at this time to generate signal F, thereby driving a relay. Consequently, a relay driving signal is formed which has invariably-constant pulse width regardless of the pulse width of a supplied operation signal. |
