Seagate Technology Incorporated

Gerald L Weispfenning

Lloyd C Goss

John Bortins

Lance Eugene Stover

Beat G Keel

Frank Edgar Stageberg

A servo head in a disk file data storage system includes two servo transducers which are connected so that noise induced by a nearby writing data head cancels. The first servo transducer, mounted on a slider, reads information stored on a servo disk. A second servo transducer, also located on the slider, is connected to the first servo transducer to produce an output signal so that noise signals induced in the first servo transducer by operation of the data transducer tend to be canceled by noise signals induced in the second servo transducer by operation of the data transducer. The two servo transducers are located such that they are closely spaced relative to the size of the servo transducers. The close proximity of the two servo transducers reduces the effect of unequal shielding from noise signals induced in the two servo transducers by the data head.

Servo head with close servo transducer placement for improved passive

A servo head in a disk file data storage system includes two servo transducers which are connected so that noise induced by a nearby writing data head will cancel. The two servo transducers are located an equal distance from the data transducer. The pole tips of the first servo transducer are positioned to read servo information stored on an adjacent servo disk. The pole tips of the second servo transducer are oriented away from the servo disk surface to prevent the second servo transducer from reading an unwanted signal from the servo disk.

Methods of improved servo head passive noise cancellation by placement

A servo head in a disk file data storage system includes at least one shield which acts to block radiation emanating from a nearby data head and thus reduce noise induced in the servo head. The shield is located on either side of an essentially flat conducting coil in a servo transducer, or a data transducer or both. The shield may be either a single layer of material or multiple layers.

Shielded servo heads with improved passive noise cancellation

A sector on a disk contains position information used to determine position error of a transducer over the disk. The sector has a normal field with a first side and a second side. The first side is oriented opposite the second side on the disk. A first quadrature field is located on the first side of the normal field and a second quadrature field is located on the second side of the normal field.

Sectored servo disk formatting

A demodulator system demodulates position information signals provided by a transducer in response to position information. The position information is read from a quadrature field and a normal field on a disk in a data storage system. A rectifier rectifies the position information signals to provide rectified position signals. An integrating capacitor integrates the rectified position signals to produce position error signals representative of trasducer position.

Sectored servo position demodulator system

Transducer position is determined relative to a disk in a data storage system. Track identification information is read from a disk in the data storage system to provide a coarse position signal identifying a track that the transducer is positioned over. Position error samples are read from a disk in the data storage system to provide a fine position signal representing transducer position error within a track that the transducer is positioned over. Then, the coarse position signal and the fine position signal are correlated so they correspond to the same track on the disk.

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Saint Paul, MN, United States of America

Gerald L Weispfenning