| 摘要 |
PURPOSE:To reject the noise produced in the leading and trailing of the rotating detection pulse signal and to make the circuit suitable for the servo circuit by digital signal processing, by constituting of R-FF, T-FF, coincidence circuit and counter circuit. CONSTITUTION:When a pulse signal 16 overlapping noise at leading and trailing is input at the input terminal 8, if the output 18 of T-FF11 is at H level, the output of a coincidence circuit 9 is at H level, and an R-FF10 is set. This output signal 19 and the reference clock signal 17 are fed to the counter circuit 14. When the output 21 of the circuit 14 is fed as the reset signal of FF10 and the clock signal of FF11, FF10 is reset and the output signal 19 is at L level. In this case, the circuit 14 is reset with the inverting signal Q' of the output signal 19. Thus, the counter output 21 is again at L level. On the other hand, the output 18 of T-FF11 is triggered with the said output signal 21 and inverted into L level. The coincidence with the L level at the trailing timing of the input signal 16 is detected at the circuit 9 and FF10 is again set. |
