公开(公告)号：US5493454A

公开(公告)日：1996-02-20

申请号：US317902

申请日：1994-10-04

申请人： Pablo A. Ziperovich ,  Xiaodong Che

发明人： Pablo A. Ziperovich ,  Xiaodong Che

IPC分类号： G11B5/09 ,  G11B20/10 ,  G11B20/12 ,  G11B20/14 ,  G11B27/36

CPC分类号： G11B20/10194 ,  G11B20/10055 ,  G11B27/36 ,  G11B20/1258

摘要： Write precompensation optimization for a partial response maximum likelihood ("PRML") magnetic recording channel adapted to a mass production environment. Optimal write precompensation may be determined by writing a tribit data pattern known to produce worst case nonlinear transition shift ("NLTS") onto a magnetic recording medium; reading back the recorded data pattern; and calculating the mean-squared error ("MSE") for one or more of the equalized data sample levels associated with the PRML channel to be optimized. The writing and reading back process is repeated with varying amounts of precompensation applied to the written pattern. The optimal amount of write precompensation is determined either by minimizing the MSE for a selected sample level or by minimizing MSE between the middle and the upper or lower of the ternary PRML sample levels.

摘要翻译： 为适应于大规模生产环境的部分响应最大似然（“PRML”）磁记录通道编写预补偿优化。 可以通过将已知产生最坏情况非线性转变位移（“NLTS”）的三位数据模式写入到磁记录介质上来确定最佳写预补偿; 读回记录数据模式; 以及计算与要优化的PRML信道相关联的一个或多个均衡数据样本水平的均方误差（“MSE”）。 重复写入和回读过程，并对写入的图案应用不同量的预补偿。 通过最小化所选样本级别的MSE或通过使三进制PRML样本级别的中间和上限或更低之间的MSE最小化来确定写入预补偿的最佳量。

公开(公告)号：US07821736B2

公开(公告)日：2010-10-26

申请号：US11399548

申请日：2006-04-06

申请人： Xiaodong Che ,  Wen-Chien Hsiao ,  Yimin Hsu ,  Vladimir Nikitin

发明人： Xiaodong Che ,  Wen-Chien Hsiao ,  Yimin Hsu ,  Vladimir Nikitin

IPC分类号： G11B5/127

CPC分类号： G11B5/1278 ,  G11B5/11 ,  G11B5/3116 ,  G11B5/3146

摘要： Write elements are discussed having a write pole and an associated trailing shield. A leading side of the trailing shield faces a trailing side of the write pole. The leading side of the trailing shield has a shape such that a center portion of the leading side has less of a separation from the trailing side of the write pole than track edge portions of the leading side of the trailing shield. An exemplary shape the leading side of the trailing shield may be a convex shape when viewed from the ABS. The shape of the leading side of the trailing shield causes the trailing shield to shunt less of the magnetic field from the trailing side of the write pole at the track edges so that the written transition at the track edge will not lag behind the written transition at the track center allowing for a straighter transition.

摘要翻译： 讨论了具有写极点和相关联的后屏蔽的写元件。 后挡板的前端面向写极的后侧。 后挡板的前侧具有这样的形状，使得前侧的中心部分比后挡板的前侧的轨道边缘部分具有比写入极的后侧更小的间隔。 当从ABS观察时，后护罩的前侧的示例性形状可以是凸形。 尾部屏蔽的前端的形状使得后屏蔽件在轨道边缘处从写入极的后侧分流较少的磁场，使得在轨道边缘处的写入的转变不会滞后于在 轨道中心允许更直接的过渡。

公开(公告)号：US07538963B2

公开(公告)日：2009-05-26

申请号：US11389827

申请日：2006-03-27

申请人： Xiaodong Che

发明人： Xiaodong Che

IPC分类号： G11B19/04

CPC分类号： G11B33/1493 ,  G11B19/04

摘要： A disk drive that protects stored data from stray magnetic fields is disclosed. Sensors for sensing stray magnetic fields are mounted to the base and/or cover of the drive and aligned with the trajectory of the movement of the read/write head. If the sensors, which have memory such as a toggle switch, are exposed to a high stray magnetic field, operation of the drive is suspended until a follow-up algorithm or protocol is implemented. The sensors can sense specific direction of stray fields. The sensor can change resistance if a high stray field is detected. The information in the sensors is collected and processed by the drive controller.

摘要翻译： 公开了一种保护存储的数据免受杂散磁场的磁盘驱动器。 用于感测杂散磁场的传感器安装到驱动器的底座和/或盖上，并与读/写头的移动轨迹对准。 如果具有诸如拨动开关的存储器的传感器暴露于高杂散磁场，则驱动器的操作被暂停，直到实现后续算法或协议。 传感器可以感测杂散场的特定方向。 如果检测到高杂散场，传感器可以改变电阻。 传感器中的信息由驱动控制器收集和处理。

公开(公告)号：US5691857A

公开(公告)日：1997-11-25

申请号：US536416

申请日：1995-09-29

申请人： James Fitzpatrick ,  Xiaodong Che

发明人： James Fitzpatrick ,  Xiaodong Che

IPC分类号： G11B5/012 ,  G11B5/48 ,  G11B5/596 ,  G11B21/10

CPC分类号： G11B5/012 ,  G11B5/4886 ,  G11B5/59627 ,  G11B5/59683

摘要： Determining a micro-jog parameter in a disk drive that employs a magneto-resistive (MR) transducer head assembly and a partial response (PRML) detector includes improved accuracy in measuring on-track signal strength by use of a matched filter technique. The matched filter includes circuitry for emulating a partial response signal expected to be produced by a selected test bit pattern prerecorded on the selected track. The matched filtering technique provides improved accuracy in measuring the detected signal strength as it provides an extremely narrow digital filter focused on the test bit pattern frequency. Improved determination of the micro-jog distance further includes measuring interference from adjacent tracks, the best error rate being achieved at micro-jog positions intermediate the maximum on-track signal strength and the minimum off-track interference. A novel digital detector for accurately measuring adjacent track interference also is disclosed.

摘要翻译： 确定采用磁阻（MR）传感器头部组件和部分响应（PRML）检测器的磁盘驱动器中的微步进参数包括通过使用匹配滤波器技术来提高测量轨道上信号强度的精度。 匹配滤波器包括用于模拟预期由预先记录在所选轨道上的选定测试位模式产生的部分响应信号的电路。 匹配滤波技术提供了测量检测信号强度的精度，因为它提供了一个集中在测试位模式频率上的极窄数字滤波器。 改进的微步距距离的确定还包括测量来自相邻轨道的干扰，在最大导轨信号强度和最小偏离磁道干扰之间的微点位置处实现最佳误码率。 公开了一种用于精确测量相邻轨道干扰的新型数字检测器。

公开(公告)号：US08120866B2

公开(公告)日：2012-02-21

申请号：US12511702

申请日：2009-07-29

申请人： Xiaodong Che ,  Zhen Jin ,  Michael Salo ,  Roger Wood

发明人： Xiaodong Che ,  Zhen Jin ,  Michael Salo ,  Roger Wood

IPC分类号： G11B27/36 ,  G11B5/03

CPC分类号： G11B5/59627 ,  G11B5/09

摘要： A method for characterizing a magnetic-recording system for the presence of adjacent-track interference and far-track interference. The method includes writing a plurality of repeating pulse-waveforms on a data track of a magnetic-recording disk at a write element of a magnetic-recording head. The method further includes reading a plurality of read-back signals from the magnetic-recording disk over a band of pseudo-data tracks offset from the data track by corresponding pseudo-data-track offsets in a radial direction of the magnetic-recording disk at a read element of the magnetic-recording head. In addition, the method includes displaying a magnetic-recording-signature map synthesized from the read-back signals from the magnetic-recording disk.

摘要翻译： 用于表征磁记录系统的方法，用于存在相邻磁道干扰和远磁道干扰。 该方法包括在磁记录头的写入元件的磁记录盘的数据轨道上写入多个重复的脉冲波形。 该方法还包括：在磁​​记录盘的数据轨道偏移的伪数据轨道的带上，通过磁记录盘的径向方向上的对应的伪数据轨偏移来读取多个读回信号， 磁记录头的读取元件。 此外，该方法包括显示从磁记录盘的回读信号合成的磁记录签名图。

公开(公告)号：US07542227B2

公开(公告)日：2009-06-02

申请号：US11824147

申请日：2007-06-29

申请人： Xiaodong Che ,  Yawshing Tang

发明人： Xiaodong Che ,  Yawshing Tang

IPC分类号： G11B21/02

CPC分类号： G11B5/6029

摘要： A hard disk drive that determines a flying height from a slope of a line created from a ratio of amplitudes of frequencies in response to impulse functions. A first set of amplitudes of reference frequencies can be determined from a reference impulse. A second set of amplitudes of data frequencies can be determined from a data impulse during operation of the disk drive. Ratios of amplitudes of the data and reference frequencies at different discrete frequencies can be plotted. The slope of the plotted line corresponds to the difference between the flying height when the reference impulse is generated and the flying height when the data impulse is generated. The disk drive may utilize the slope in a feedback routine to control the flying height.

公开(公告)号：US20090002870A1

公开(公告)日：2009-01-01

申请号：US11824147

申请日：2007-06-29

申请人： Xiaodong Che ,  Yawshing Tang

发明人： Xiaodong Che ,  Yawshing Tang

IPC分类号： G11B21/02

CPC分类号： G11B5/6029

摘要： A hard disk drive that determines a flying height from a slope of a line created from a ratio of amplitudes of frequencies in response to impulse functions. A first set of amplitudes of reference frequencies can be determined from a reference impulse. A second set of amplitudes of data frequencies can be determined from a data impulse during operation of the disk drive. Ratios of amplitudes of the data and reference frequencies at different discrete frequencies can be plotted. The slope of the plotted line corresponds to the difference between the flying height when the reference impulse is generated and the flying height when the data impulse is generated. The disk drive may utilize the slope in a feedback routine to control the flying height.

摘要翻译： 一个硬盘驱动器，用于根据脉冲函数的频率幅度比，确定从一条线的斜率上的飞行高度。 参考频率的第一组幅度可以从参考脉冲确定。 可以在磁盘驱动器的操作期间从数据脉冲确定数据频率的第二组振幅。 可以绘制不同离散频率下的数据和参考频率的幅度比。 绘制线的斜率对应于当产生参考脉冲时的飞行高度与产生数据脉冲时的飞行高度之间的差。 磁盘驱动器可以利用反馈程序中的斜率来控制飞行高度。

公开(公告)号：US20080100943A1

公开(公告)日：2008-05-01

申请号：US11591745

申请日：2006-10-31

申请人： Xiaodong Che

发明人： Xiaodong Che

IPC分类号： G11B27/36

CPC分类号： G11B20/10009 ,  G11B2220/2516

摘要： Method calibrates an assembled hard disk drive for read head accessing rotating disk surface, by estimating non-linearity of that playback device based on two data patterns, which have a short transition-pair waveform and a long transition-pair waveform. By linearly constructing a simulated long transition-pair waveform from the short transition-pair waveform and aligning it with the long transition-pair waveform, non-linear distortion is estimated, creating the transfer curve as product of this process. The transfer curve is used to compensate the read data of a track to create the adjusted read data, which is used to decode the track being read. The adjusted read data is the product of this process. The hard disk drive including the transfer table. Second method using transfer table to create adjusted read data for track, the processor, embedded circuit and hard disk drive implementing this method. Manufacturing embedded circuit as product.

摘要翻译： 通过估计具有短的跃迁对波形和长的转换对波形的两种数据模式，回放装置的非线性度量，校准组装的硬盘驱动器，用于读取磁头访问旋转磁盘表面。 通过从短的跃迁对波形线性构造模拟的长跃迁对波形并将其与长的跃迁对波形对准，估计非线性失真，从而产生作为该过程的乘积的转移曲线。 传输曲线用于补偿轨道的读取数据，以创建调整后的读取数据，该读取数据用于对所读取的轨道进行解码。 调整后的读取数据是此过程的产物。 硬盘驱动器包括传输表。 第二种方法使用传输表创建调整读取数据的轨道，处理器，嵌入式电路和硬盘驱动器实现这种方法。 制造嵌入式电路作为产品。

公开(公告)号：US20080080086A1

公开(公告)日：2008-04-03

申请号：US11542354

申请日：2006-10-02

申请人： Xiaodong Che ,  Xiao Z. Wu

发明人： Xiaodong Che ,  Xiao Z. Wu

IPC分类号： G11B21/02 ,  G11B27/36

CPC分类号： G11B5/6005 ,  G11B5/455 ,  G11B5/6076

摘要： A low flying slider detector is disclosed. In one embodiment a surface is provided. In addition, a suspender is provided for receiving and flying a slider above the surface. A detector is also provided for detecting a low flying slider flying above the surface wherein the detector does not require measuring of the slider fly height to detect the low flying slider and wherein the detecting of the low flying slider is performed at least at a slider level of assembly.

摘要翻译： 公开了一种低飞行滑块检测器。 在一个实施例中，提供了一个表面。 此外，设置悬挂件用于在表面上接收和飞行滑块。 还提供了一种用于检测在表面上方飞行的低飞行滑块的检测器，其中检测器不需要测量滑块飞行高度以检测低飞行滑块，并且其中低飞行滑块的检测至少在滑块级别 的装配。

公开(公告)号：US20080055772A1

公开(公告)日：2008-03-06

申请号：US11698751

申请日：2007-01-26

申请人： Chris McMillan ,  Umesh Chandra ,  Yawshing Tang ,  Xiaodong Che ,  Hoyul Bang

发明人： Chris McMillan ,  Umesh Chandra ,  Yawshing Tang ,  Xiaodong Che ,  Hoyul Bang

IPC分类号： G11B5/52

CPC分类号： G11B19/041 ,  G11B5/455 ,  G11B5/58

摘要： A Pre-Contact Signal Detector (PCSD) used to predict contact between read-write head and disk surface. A preamplifier may include the PCSD. A main flex circuit may include the preamplifier. A head stack assembly may include the main flex circuit. An embedded circuit may use a pre-contact alert circuit, which may also be included in the PCSD and/or the preamplifier, also the main flex circuit, the head stack assembly. A hard disk drive may include the head stack assembly communicating with the embedded circuit. Manufacturing methods for these and their products of the manufacturing processes, including the program system.

摘要翻译： 用于预测读写头和磁盘表面之间的接触的预接触信号检测器（PCSD）。 前置放大器可以包括PCSD。 主柔性电路可以包括前置放大器。 磁头堆叠组件可以包括主柔性电路。 嵌入式电路可以使用预接触警报电路，其也可以包括在PCSD和/或前置放大器中，以及主柔性电路，磁头堆叠组件中。 硬盘驱动器可以包括与嵌入式电路通信的磁头堆叠组件。 这些制造方法及其制造过程的制造过程，包括程序系统。