| 摘要 |
PURPOSE:To reduce the chip size of an IC by constituting the phase locked loop of plural VCOs having respectively different voltage-frequency conversion coefficients and a selector circuit for selecting the outputs of plural VCOs. CONSTITUTION:A VCO 3 having a larger Kv inputs the output 8 of an LPF 2, executes the voltage frequency conversion of the input and outputs the converted result. When the input signal of read data 6 is included in a sink area, the selector circuit 5 selects the output 9 of the VCO 3 having the larger Kv to allow the input to rapidly follow a reference clock. When the input signal of the read data 6 is in a data area, the circuit 5 selects the output 10 of a VCO 4 having a smaller Kv to allow the input to slowly follow the reference clock so as not to follow phase variation such as a peak shift. |
