Method for synchronizing the write current for magnetic recording with the bit islands on discrete bit patterned media
AssigneeSeagate Technology LLC
InventorsKarl A. Belser, Stephen J. Hrinya
Life of this patent
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Abstract
A patterned recording media is comprised of a combination of raised features and depressed features in or on the surface of the recording disk. A depressed feature is known as a pit, while a raised feature is known as an island. The islands form areas where one or more data bits can be written. The recording head is synchronized to the discrete bit pattern by determining the correct clock cycle (phase) and clock count within the clock cycle.
Claims30
A method for synchronizing a recording head to a patterned magnetic media, the method comprising:
- determining a phase correction value and adjusting the phase of the recording head wherein this step is performed as a calibration procedure to determine an initial phase correction value Po;
- and
- determining the location of an initial bit island where a first data bit is to be processed by the recording head.
The method for synchronizing a phase of a recording head with a patterned recording media, the method comprising:
- selecting at least one starting delay value;
- writing at least one pattern on the patterned recording media wherein the act of writing at least one pattern on the patterned recording media uses at least two different delay values;
- reading the at least one pattern;
- and
- determining a phase correction value and adjusting the phase of the recording head so that the phase of the recording head is synchronized with the phase of the patterned recording media.
A method for determining allocation of an initial bit island where a first data bit on a patterned recording media is to be processed by a recording head, comprising:
- writing at least one pattern on the patterned recording media, further comprising writing the at least one pattern as a combination of ones and zeros, wherein with each successive written pattern the at least one pattern is sequentially shifted in a particular direction;
- reading the at least one pattern;
- and
- determining the location of the initial bit island based upon the resulting written at least one pattern.
A phase detector circuit that synchronizes a recording head to a patterned recording media, comprising:
- at least one phase detector;
- at least one filter coupled to the output of the at least one phase detector;
- at least one track and hold circuit coupled to the output of the at least one filter;
- at least one clock circuit coupled to the output of the at least one track and hold circuit;
- and
- at least two divider circuits coupled to the output of the at least one clock circuit.
A method for synchronizing the phase of a recording head to a patterned recording media, comprising
- determining a phase correction value Po including:
- selecting at least one starting delay value;
- writing at least one pattern on the patterned recording media by writing a particular pattern on the patterned recording media using at least two different delay values;
- reading the at least one pattern;
- determining a phase correction value and adjusting the delay of the recording head so that the phase of the recording head is synchronized with the phase of the patterned recording media;
- and
- periodically measuring and correcting any variations in phase.
Dependencies are inferred from the claim text.