公开(公告)号：JP2002237004A

公开(公告)日：2002-08-23

申请号：JP2002021055

申请日：2002-01-30

Applicant: IBM

Inventor： LAMBERTS BERND

IPC: G11B5/09 ,  G11B5/00 ,  G11B5/012 ,  G11B5/02 ,  G11B5/035 ,  G11B5/31 ,  G11B20/10 ,  G11B27/36 ,  G11B33/14

Abstract: PROBLEM TO BE SOLVED: To provide a method and device for dynamically adjusting head currents. SOLUTION: The efficiency and data integrity of a data storage device are improved by dynamically adjusting a particular operation parameter to its optimal value during the operation of the storage device. The physical properties of the storage device such as a hard disk drive are measured during the process of manufacturing, thereby obtaining the dependency of the storage device on environmental conditions, under which the storage device is operated. The effects of the physical properties and the operation environment of the storage device on its performance are obtained, and a writing current optimal value of the storage device is stored in a lookup table. A temperature in which the storage device is operated is used as a reference to data stored in the lookup table. The optimal value of pre-compensation delay is also stored. During the operation of the storage device, the temperature of an operation environment is sensed, and used as a reference to the lookup table. The optimal values of a writing current and pre-compensation delay corresponding to the sensed temperature are taken out, and the writing current and the pre-compensation delay of the storage device are accordingly adjusted.

公开(公告)号：JP2002197850A

公开(公告)日：2002-07-12

申请号：JP2001332156

申请日：2001-10-30

Applicant: IBM

Inventor： GILLIS DONALD RAY ,  LAMBERTS BERND ,  SCHOUTERDEN KRIS V

IPC: G01D5/16 ,  G11B5/00 ,  G11B5/012 ,  G11B5/39 ,  G11B5/455 ,  G11B33/10 ,  G11B33/14 ,  H01L43/02 ,  H01L43/08

Abstract: PROBLEM TO BE SOLVED: To provide a magnetic recording disk drive having a magneto- resistive(MR) read head and a control unit having an operating pressure logic function which responds with a thermal resistance signal included in a feedback signal from the MR read head. SOLUTION: The thermal conductivity of the air inside a hard disk drive is swayed by air pressure. The fluctuation of heat conductance from the MR read head to the circumference of the MR read head within the hard disk affects the temperature of the MR head and therefore affects the thermal resistance of the MR read head. The temperature of the head can be determined in accordance with the thermal resistance signal. The pressure can be determined in accordance with the prescribed relations among the temperature, internal pressure and internal operating temperature of the MR read head by applying the same.