| 摘要 |
PROBLEM TO BE SOLVED: To make the pulse width of a noise pulse to be removed selectively switchable, while the number of constituent elements is minimized and the constituent elements are kept in fixed type constituent elements. SOLUTION: A digital filter device is constituted, in such a way that the device is provided with pulse period width setting and changing circuits 60 and 62 which can output a noise removing pulse signal CKIN, having a changeable pulse period width Tv such that it is broader than the pulse period width (one-period width) Tc of a reference clock pulse signal CK and the circuits 60 and 62 are connected to flip-flops 51A-51C which decide the pulse width of a noise pulse Sn to be removed, and asynchronous pulse signals IN and noise-removed pulse signals CKIN can be inputted to the flip-flops 51A-51C from the outside. Then the pulse period width Tv of the signals CKIN are changed, while the number of stages (3) of the flip-flops 51A-51C is fixed as is. Therefore, the digital filter device is formed capable of selectively switching the pulse width of the noise pulse Sn to be removed. |
