| 摘要 |
PURPOSE:To eliminate the effect due to residual noise without any hindrance to normal data reception by setting an offset voltage between an inverting level and an input signal to prevent the detection of residual noise in waveform-shaping before delay detection. CONSTITUTION:A level shift circuit 6 decreasing (or increasing) the DC level of an input signal to a waveform-shaping circuit 2 less than the inverting level (threshold level) of the circuit 2 is provided between a reception BPF1 and the waveform shaping circuit 2. Though the inverting level is VDD/2, the DC level DC of the input signal supplied to a non-inverting input is decreased to a value decided by the voltage dividing ratio of resistors R1 and R2. When the offset voltage VOS=VDD/2-DC by the voltage dividing ratio exceeds the amplitude of the residual noise, no random pattern is regenerated. |
