JPS5451709A - Bit phase synchronizing circuit - Google Patents

Abstract

PURPOSE:To secure the bit phase synchronization between the digital units through a simple circuit with no piling of the timing matching signals in case the digital signals are transferred between plural units of devices via the same reference timing signal. CONSTITUTION:The following circuits are installed: timing signal generator circuit 12 which generates timing signal S4 and S5 of different phases to each other based on reference timing signals S1; changing point detecting circuit 11 which detects the changing point of receiving digital signal S2; and phase difference detecting circuit 13 which detects the phase difference between the output of circuit 11 and the timing signal S4 or S5. In addition, selector circuit 17 which the phase producing no decision error for signal S2 among two timing signals based on the output result of circuit 13 is added, along with retiming circuit 21 which gives retiming to signal S2 via retiming signal S9 selected through circuit 17. Thus, bit phase synchronous circuit 10 is constituted.