The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 08, 2007
Filed:
Dec. 27, 2005
Xiaodong Che, Saratoga, CA (US);
Weidong Huang, San Jose, CA (US);
Terence Tin-lok Lam, Cupertino, CA (US);
Zhong-heng Lin, Santa Clara, CA (US);
Alex Shteyn, Sunnyvale, CA (US);
Xiaodong Che, Saratoga, CA (US);
Weidong Huang, San Jose, CA (US);
Terence Tin-Lok Lam, Cupertino, CA (US);
Zhong-heng Lin, Santa Clara, CA (US);
Alex Shteyn, Sunnyvale, CA (US);
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
A system and method for determining head-disk contact (HDC) in a magnetic recording disk drive uses the signal from the magnetoresistive (MR) read head. The analog MR signal is digitized and input to a digital signal processor with circuitry and/or software for integrating the signal amplitude over a low-frequency range. The calculated value from the integration when the slider is out-of-contact with the disk is a reference value. The same integration is then performed during operation of the disk drive and the measured value is compared to the reference value. If the measured value exceeds the reference value by some predetermined amount, this is an indication of the onset of HDC or that HDC has occurred. The method can be used in head-disk testers to facilitate the design and testing of disk drive components, such as slider-suspension assemblies and fly-height actuators located on the slider to alter the head-disk spacing, and in disk drives to control fly-height actuators and to take corrective action prior to HDC.