PURPOSE: To reduce signal distortion generated by the variation of a pulse width in case of receiving a digital signal by connecting two comparators having the almost same switching speed so as to execute an inverting operation each other.
CONSTITUTION: A digital signal from a line 11 is applied to comparators 13, 14 after its level is adjusted by a pre-amplifier 12. A signal for determining a discriminating level Vth is applied to the comparators 13, 14 from a discriminating level setting circuit 15. The comparators 13, 14 have the same switching speed, and have such a relation as a logical state of an output is inverted each other. That is to say, a non-inversion input and an inversion input of the comparator 13 are connected to an inversion input and a non-inversion input of the other comparator 14, respectively. Outputs from the comparators 13, 14 are provided to a flip-flop 16. The flip-flop 16 consists of two NAND gates 17, 18. The output from the comparator 13 is provided to the NAND gate 17 as a reset input S through a line 19.
FUJII YASUHIRO
OKAMOTO KUNINORI
