Disk drive with servo synchronous recording
AssigneeHitachi Global Storage Technologies Netherlands B.V.
InventorsSteven R. Hetzler, William John Kabelac
Life of this patent
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Abstract
A read clock circuit for a disk drive includes a phase-locked loop/voltage controlled oscillator (VFO/PLL) and a frequency synthesizer. The VFO/PLL receives a servo sector transition signal that is related to detected transitions in a servo sector field of a magnetic recording disk, and outputs a servo frequency signal that is synchronous to the servo sector transition signal. The frequency synthesizer receives the servo frequency signal and generates the read clock signal that is synchronous with the servo frequency signal. In a banded recording disk drive the frequency synthesizer generates a unique read clock signal for each data band.
Claims18
A read clock circuit for a recording disk system that has servo sectors, the circuit comprising:
- a variable frequency oscillator/phase-locked loop (VFO/PLL) receiving a servo sector transition signal from transitions detected in a servo sector and outputting a servo frequency signal that is synchronous to the servo sector transition signal, and
- a frequency synthesizer generating a read clock signal based on the servo frequency signal, the read clock signal being synchronous with the servo sector transition signal.
A banded recording sector servo disk drive comprising:
- a data recording disk having a plurality of data bands, each data band having data recorded at a unique frequency, and a plurality of servo sectors extending in a radial direction across the bands;
- a variable frequency oscillator/phase-locked loop (VFO/PLL) for receiving a servo sector transition signal from transitions detected in a servo sector and outputting a servo frequency signal that is synchronous to the servo sector transition signal;
- a frequency synthesizer receiving the servo frequency signal and generating a plurality of unique read clock signals based on the servo frequency signal, the read clock signal being synchronous with the servo sector transition signal, and each unique read clock signal corresponding to a unique frequency of a data band;
- and
- a controller coupled to the frequency synthesizer and providing a data band identification signal to the frequency synthesizer.
Dependencies are inferred from the claim text.