| 摘要 |
PURPOSE:To provide a means which speedily and stably performs phase shift even when data with not-aimed pulse interval exists in input data when a phase synchronized oscillator circuit to be used for a magnetic disk device is synchronized in phase with the input data. CONSTITUTION:The pulse interval of the input data is measured by a pulse interval detection circuit 1, and when the data have the not-aimed pulse interval, the oscillation of a voltage controlled oscillator circuit 7 is stopped, gate circuits 3 and 4 are closed, and supplying the input data and the signal of the voltage controlled oscillator circuit 7 to a phase comparator circuit 5 is stopped. When the data has the aimed pulse interval, the oscillation of the voltage controlled oscillator circuit 7 is started, the gate circuits 3 and 4 are opened, the input data, the signal of the voltage controlled oscillator circuit 7 are supplied to the phase comparator circuit 5 and the phase synchronized oscillator circuit synchronizes in phase with the input data. |
