| 摘要 |
PURPOSE:To suppress an impulsive noise by providing a single stable multi-vibrator means, an AND gate means and a delay circuit means, suppressing a pulse signal, which is shorter than the operating time of the single stable multi-vibrator means, and outputting an output signal to an input signal which is longer than the operating time. CONSTITUTION:When a short intermittent signal is inputted to an input terminal IN and this signal is a short pulse to be erased in a time which is shorter than an operating time tau of the single stable multi-vibrator means, a short whisker-shaped pulse is outputted. Since this pulse is absorbed in a delay circuit LG, an output terminal OUT is left to be an L level and nothing is outputted. Next, when the pulse to be longer than the above mentioned tau is inputted, since the input signal of the IN goes to be H, the two inputs of the AND gate go to be H together and the OUT goes to be the H level. Then, the output signal is outputted. This output signal is outputted until there is no input signal of the IN. Accordingly, when a pulse noise suppressing circuit is used for the abnormality display lamp or warning buzzer, etc., of a supervising system, intermittence on the basis of the noise, etc., is erased. |
