Magnetic disk device capable of correcting servo demodulation position
AssigneesKabushiki Kaisha Toshiba, Toshiba Electronic Devices & Storage Corporation
InventorNaoki Tagami
Life of this patent
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Abstract
According to one embodiment, a magnetic disk device includes a disk including two first servo sectors and at least a second servo sector, a head, and a controller, wherein the first servo sector includes burst data and a first data pattern written before the circumferential direction of the burst data, the second servo sector includes the burst data, the first data pattern, and a second data pattern written after the circumferential direction of the burst data, a first frequency of the first data pattern is different from a second frequency of the second data pattern, and a first length of the first data pattern is different from a second length of the second data pattern.
Claims8
A magnetic disk device comprising:
- a disk comprising two first servo sectors arranged side by side in a circumferential direction and at least a second servo sector located between the two first servo sectors;
- a head that writes data to the disk and reads data from the disk;
- and
- a controller that demodulates all data of the first servo sector and demodulates data of part of the second servo sector,
- wherein the first servo sector comprises burst data and a first data pattern written before the circumferential direction of the burst data,
- the second servo sector comprises the burst data, the first data pattern written before the circumferential direction of the burst data, and a second data pattern written after the circumferential direction of the burst data,
- a first frequency of the first data pattern is different from a second frequency of the second data pattern,
- a first length in the circumferential direction of the first data pattern is different from a second length in the circumferential direction of the second data pattern, and
- the first data pattern comprises a preamble, and the first frequency is equal to a third frequency of the preamble.
A magnetic disk device comprising:
- a disk comprising two first servo sectors arranged side by side in a circumferential direction and at least a second servo sector located between the two first servo sectors;
- a head that writes data to the disk and reads data from the disk;
- and
- a controller that demodulates all data of the first servo sector and demodulates data of part of the second servo sector,
- wherein the first servo sector comprises burst data and a first data pattern written before the circumferential direction of the burst data,
- the second servo sector comprises the burst data, the first data pattern written before the circumferential direction of the burst data, and a second data pattern written after the circumferential direction of the burst data,
- a first frequency of the first data pattern is different from a second frequency of the second data pattern,
- a first length in the circumferential direction of the first data pattern is different from a second length in the circumferential direction of the second data pattern, and
- the first servo sector comprises a third data pattern written after the circumferential direction of the burst data, a fifth frequency of the third data pattern is different from the second frequency of the second data pattern, and the third length in the circumferential direction of the third data pattern is different from the second length in the circumferential direction of the second data pattern.
Dependencies are inferred from the claim text.