Browse Prior Art Database

Independent Track Pitch

IP.com Disclosure Number: IPCOM000117988D
Original Publication Date: 1996-Aug-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 36K

Publishing Venue

IBM

Related People

Kitazaki, N: AUTHOR [+4]

Abstract

This invention makes it possible to have a flexible track pitch of HDD drive. This is the invention of the surface format of the HDD application with the conventional embedded servo algorithm.

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This is the abbreviated version, containing approximately 100% of the total text.

Independent Track Pitch

      This invention makes it possible to have a flexible track pitch
of HDD drive.  This is the invention of the surface format of the HDD
application with the conventional embedded servo algorithm.

      In current HDD application, track pitch is determined by the
pitch of the servo pattern which is written (embedded) on the disk
surface.  The center of the data track is corresponding to the center
of the servo pattern.

      This invention defines the correspondence between the center
of the data track and the servo data information.  Servo information
consists of the track number information and the Position Error
Signal (PES) within one track pitch.  In the conventional surface
format, only  track number information was used to relate the data
track and servo pattern.  This invention uses both track number and
PES (8bit;0-255) for  that.  The Figure shows a relation between
servo pattern and data track  in a conventional format and in a new
format.

      By using this algorithm, any track pitch with the fixed servo
pattern can be obtained.  In order to relate the servo pattern to the
data track, an internal table on RAM is used.