| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a phase comparator circuit and a PLL circuit incorporating it, which can correct LSB errors in code conversion of the wave data read from a magnetic recording medium, avoid increase in circuit scale and in delay, while realizing high speed phase difference calculations. <P>SOLUTION: A correction circuit 140 detects the state depending on the ternary conversion of the wave data when two consecutive wave data are code converted, and holds the data '1' in the first holding circuit to input to the carry input CI of an adder circuit 150 based on the detected result. It outputs the data '1' retained in the first holding circuit to input to the carry input CI of the adder circuit 150, when the ternary data of the inputted wave data takes a value other than '-1'. Thus, -1LSB errors made in adding are corrected, and the phase errors are corrected by integrating them in the following low-pass filter. <P>COPYRIGHT: (C)2003,JPO |
