Fujitsu Corporation

Kenji Itou

Isamu Tomita

Nobuyuki Suzuki

Hiroshi Tsurumi

Tomoaki Saito

Toshiki Kimura

Kouhei Takamatsu

In an apparatus for recording and/or reproducing information, which reproduces servo information being recorded on a medium and conducts a tracking operation based on the servo information, a power save part conducts a power save operation by reducing an operation clock frequency in accordance with a predetermined process during a tracking operation, during a seek operation, and/or during spindle motor startup.

Apparatus for recording or/and reproducing information and method for reducing power consumption thereof

Disclosed is an off-track correcting method for a disk apparatus for measuring an off-track correction value by use of servo data on a data surface. The data surface on a disk medium is recorded with servo data for an off-track measurement. The data head seals a cylinder position recorded with the off-track measurement servo data. It is determined whether or not this cylinder position is a sensitivity abnormal position of the cylinder. The data head reads a first item of servo data after offset-moving the data head by a predetermined quantity on inner and outer sides of the disk medium, corresponding to detecting that the data head is located in the sensitivity abnormal position. An off-track correction value in the cylinder position is calculated from the plural pieces of first servo data read finally in a plurality of reading positions. This, even when enhancing a track density, the precise off-track correction value can be thereby measured.

Off-track correcting method of disk apparatus and a disk apparatus using

A position sensitivity adjusting method for a disk apparatus and a disk apparatus using the same for adjusting an AGC (Automatic Gain Control) amplifier for amplifying a servo signal on a servo surface of a disk medium, involves positioning a servo head at a boundary of tracks on the servo surface. The method then includes setting a plurality of different adjustment values in the AGC amplifier, reading two position signals through the servo head for each adjustment value, and calculating a dispersion value of the position signals for each adjustment value. After the adjustment value for the AGC amplifier which provides the minimum dispersion value is acquired from the calculated dispersion values, the acquired adjustment value is set in the AGC amplifier. With the adjusting method, even when offset compensation for positioning the servo head at a track boundary is executed, a positioning error can be prevented.

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Kawasaki, Japan

Kenji Itou