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:
Mar. 04, 2014
Filed:
Jul. 01, 2011
Siuman Mok, Hong Kong, CN;
Hokei Lam, Hong Kong, CN;
Cheukwing Leung, Hong Kong, CN;
Juren Ding, Hong Kong, CN;
Rongkwang NI, Hong Kong, CN;
Wanyin Kwan, Hong Kong, CN;
Cheukman Lui, Hong Kong, CN;
Chiuming Lueng, Hong Kong, CN;
Siuman Mok, Hong Kong, CN;
Hokei Lam, Hong Kong, CN;
Cheukwing Leung, Hong Kong, CN;
Juren Ding, Hong Kong, CN;
Rongkwang Ni, Hong Kong, CN;
Wanyin Kwan, Hong Kong, CN;
Cheukman Lui, Hong Kong, CN;
Chiuming Lueng, Hong Kong, CN;
SAE Magnetics (H.K.) Ltd., Hong Kong, CN;
Abstract
A method for measuring longitudinal bias magnetic field in a tunnel magnetoresistive sensor of a magnetic head, the method includes the steps of: applying an external longitudinal time-changing magnetic field onto the tunnel magnetoresistive sensor; determining a shield saturation value of the tunnel magnetoresistive sensor under the application of the external longitudinal time-changing magnetic field; applying an external transverse time-changing magnetic field and an external longitudinal DC magnetic field onto the tunnel magnetoresistive sensor; determining a plurality of different output amplitudes under the application of the external transverse time-changing magnetic field and the application of different field strength values of the external longitudinal DC magnetic field; plotting a graph according to the different output amplitudes and the different field strength values; and determining the strength of the longitudinal bias magnetic field according to the graph and the shield saturation value.