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:
Jul. 19, 2011
Filed:
May. 24, 2007
Junzoh Noda, Kanagawa, JP;
Masahiro Shimizu, Kanagawa, JP;
Kouji Matsuda, Kanagawa, JP;
Hiroyasu Masuda, Kanagawa, JP;
Atsushi Tobari, Kanagawa, JP;
Junzoh Noda, Kanagawa, JP;
Masahiro Shimizu, Kanagawa, JP;
Kouji Matsuda, Kanagawa, JP;
Hiroyasu Masuda, Kanagawa, JP;
Atsushi Tobari, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the present invention help to efficiently determine the appropriate setting of the write current of a magnetic head relative to temperature. According to one embodiment, a test computer determines the set value of a write current as a function of temperature for each head device portion from the relationship between a write current and an error rate. A test execution controller sets a selected head device portion and a write current to an AE, and writes data on a magnetic disk using the components in a HDD. The test execution controller reads the written data, and the error rate of the data from an error correcting section. The test execution controller repeats the same process with the write current varied. Upon completion of the measurement at the preset write currents, the test execution controller transfers the measurement data to the test computer.