| 摘要 |
PURPOSE:To prevent a duty ratio of an output digital signal from being affected by a level of an input digital signal by providing a reference voltage of a comparator circuit based on the duty ratio of a bit synchronizing signal. CONSTITUTION:A serial digital signal including the bit synchronizing signal from a serial data generator 11 becomes an input digital signal 101 via a filter 12 and an analog transmission line 13 and is fed to a comparator 3. An output digital signal of the comparator 3 is given to a switch and a shift register 16 and becomes a clock signal 116 in synchronizing with the bit synchronizing signal included in the output digital signal 103. The clock signal 116 is given to filter 17 and becomes a reference voltage 117 of a level proportional of the duty ratio of the bit synchronizing signal. Since the reference voltage is set in this way, the duty ratio of the output digital signal is not affected by the level of the input digital signal. |
