公开(公告)号：US20120249130A1

公开(公告)日：2012-10-04

申请号：US13067887

申请日：2011-07-01

申请人： Siuman MOK ,  Hokei LAM ,  Cheukwing LEUNG ,  Juren DING ,  Rongkwang NI ,  Wanyin KWAN ,  Cheukman LUI ,  Chiuming LUENG

发明人： Siuman MOK ,  Hokei LAM ,  Cheukwing LEUNG ,  Juren DING ,  Rongkwang NI ,  Wanyin KWAN ,  Cheukman LUI ,  Chiuming LUENG

IPC分类号： G01R33/18

CPC分类号： G01R33/098

摘要： 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.

摘要翻译： 一种用于测量磁头的隧道磁阻传感器中的纵向偏置磁场的方法，所述方法包括以下步骤：将外部纵向时变磁场施加到隧道磁阻传感器上; 在外部纵向时变磁场的应用下，确定隧道磁阻传感器的屏蔽饱和度值; 将外部横向时变磁场和外部纵向直流磁场施加到隧道磁阻传感器上; 在外部横向时变磁场的应用和外部纵向直流磁场的不同场强值的应用中确定多个不同的输出幅度; 根据不同的输出幅度和不同的场强值绘制图形; 并根据曲线图和屏蔽饱和度值确定纵向偏置磁场的强度。

公开(公告)号：US20130204590A1

公开(公告)日：2013-08-08

申请号：US13368762

申请日：2012-02-08

申请人： Hokei LAM ,  Cheukman LUI ,  Chiuming LUENG ,  Kaichiu CHEUNG ,  Wahchun CHAN ,  Juren DING ,  Rongkwang NI

发明人： Hokei LAM ,  Cheukman LUI ,  Chiuming LUENG ,  Kaichiu CHEUNG ,  Wahchun CHAN ,  Juren DING ,  Rongkwang NI

IPC分类号： G06F17/10

CPC分类号： G11B5/455 ,  G11B19/048

摘要： A spectral simulation method during a noise testing for a magnetic head, includes steps of (a1) detecting several first noise profiles for several magnetic head samples under a first frequency bandwidth range by a dynamic testing machine; (b1) separating each first noise profile into at least two noise curves including a first noise curve and a second noise curve at a predetermined frequency bandwidth, wherein the first noise curve has a frequency bandwidth range lower than that of the second noise curve; (c1) fitting several mathematical equations according to the second noise curves; and (d1) establishing a correlative equation among the mathematical equations, so as to simulate the second noise curve for each magnetic head. The present invention can simulate a second noise curve of the noise profile in a higher frequency bandwidth and establishing the correlative equation according to the second noise curve.

摘要翻译： 在磁头的噪声测试期间的光谱模拟方法包括以下步骤：（a1）通过动态测试机检测在第一频率带宽范围内的几个磁头样本的几个第一噪声分布; （b1）将每个第一噪声分布分解成包括预定频率带宽的第一噪声曲线和第二噪声曲线的至少两个噪声曲线，其中所述第一噪声曲线具有低于所述第二噪声曲线的频带宽度范围; （c1）根据第二噪声曲线拟合几个数学方程; 和（d1）在数学方程之间建立相关方程，以便模拟每个磁头的第二噪声曲线。 本发明可以模拟较高频带宽噪声分布的第二噪声曲线，并根据第二噪声曲线建立相关方程。