Patent ID: 6262857
Filing Date: 2001-07-17
Classification: G11B

Abstract:
A disk drive comprising:a disk having a disk surface;the disk surface having a plurality of tracks arranged in an embedded servo format including a plurality of radially-extending user data regions and a plurality of radially-extending servo data regions;each data region having a plurality of data zones in each of which user data are stored in a plurality of track segments at a data channel frequency particular to that data zone;each servo region having a plurality of servo zones in each of which servo data are stored in a plurality of track segments at a servo channel frequency particular to that servo zone, wherein in at least one of the tracks having servo data and user data, the servo channel frequency differs from the data channel frequency;each servo region further including in each track segment a predetermined sync mark bit pattern disposed in a position such that the sync mark bit patterns in the servo region are radially aligned with one another;means operative during a user-data read operation for reading data from the disk surface to produce a time-multiplexed analog read sign that during a revolution of the disk:represents servo data during each of a first set of time intervals;repetitiously represents the sync mark bit pattern at a substantially fixed timing interval; andrepresents user data during each of a second set of time intervals; anda read channel for processing the analog read signal to recover the data that the analog read signal represents.