| 摘要 |
PURPOSE:To position a data in the center of a discriminating window at all times regardless of variation of data transfer rate of a data memory. CONSTITUTION:Flip-flop circuits A2-D5 are constituted to output pulses having pulse width of DELTAt+T/2 and DELTAt+3T/2 when the data is shifted by DELTAt from the center of data discriminating window having width T. The flip-flop circuits A2 and D5 are connected, at the output thereof, with lowpass filters A6 and B7 which is further connected with an attenuator 8. An operational amplifier 9 receives outputs from the lowpass filter A6 and the attenuator 8 to produce a differential voltage and charges a capacitor 11 through a switch being controlled by an external signal. Charging voltage of the capacitor 11 is fed back, as a delay voltage control voltage, to a delay circuit 1 which then delays a data pulse (a). According to the constitution, delay time of the delay circuit 1 is controlled to position the data in the center of the data discriminating window regardless of variation of data transfer rate. |
