| 摘要 |
PURPOSE:To accurately convert a mountain-shaped input signal such as a triangular wave into a rectangular wave synchronizing with it by receiving an input signal and generating a differential signal, comparing its value with a threshold value and changing the state according to their large-small relation, and outputting the rectangular wave. CONSTITUTION:The input signal Si is supplied to one terminal of an operational amplifier 11 through a capacitor C and fed back through a resistance R, and a set bias potential is applied to the other terminal by resistances 12 and 13. A CR time constant is made small by using an operational amplifier, so the output differential signal Sd is already close to a rectangular wave. A comparing circuit 20 receives the signal Sd at one terminal of a comparator 21 and the threshold value TH set by the resistances 22 and 23 at the other terminal. The threshold value TH is set equal to the mean level of the differential signal Sd. The output so of the comparator 21 is the rectangular wave which has a 50% duty ratio to a right-left symmetrical triangular wave input and synchronizes with the input wave. |
