公开(公告)号：US5168413A

公开(公告)日：1992-12-01

申请号：US621010

申请日：1990-11-30

申请人： Jonathan D. Coker ,  Richard L. Galbraith ,  Paul P. Howard ,  Gregory J. Kerwin ,  Gordon J. Smith

发明人： Jonathan D. Coker ,  Richard L. Galbraith ,  Paul P. Howard ,  Gregory J. Kerwin ,  Gordon J. Smith

IPC分类号： G11B20/12 ,  G11B19/04 ,  G11B21/21 ,  G11B27/36 ,  G11B33/10

CPC分类号： G11B27/36 ,  G11B19/04 ,  G11B21/21 ,  G11B33/10 ,  G11B20/10055

摘要： A method and apparatus are provided for measuring flying height changes of a transducer head relative to a disk surface of a rotating disk in a disk file. A predetermined pattern is written on at least one predetermined region of the disk file. The predetermined region is normally not rewritten during operation of the disk file. At least one readback signal is sensed from at least one predetermined region of the disk surface. A plurality of sample values are identified corresponding to each readback signal. A change in the flying height is calculated utilizing the identified sample values. A frequency equalization number K can be utilized to calculate the magnitude and sign of the flying height change. Alternatively, real-time digital analysis of a predetermined pattern written on at least one predetermined region of the disk surface can be utilized to calculate the magnitude and sign of the flying height change.

摘要翻译： 提供一种用于测量换能器头相对于盘文件中的旋转盘的盘表面的飞行高度变化的方法和装置。 预定图案被写在盘文件的至少一个预定区域上。 通常在磁盘文件的操作期间不改写预定区域。 从盘表面的至少一个预定区域感测至少一个回读信号。 对应于每个回读信号识别多个样本值。 使用识别的样本值计算飞行高度的变化。 可以使用频率均衡数K来计算飞行高度变化的大小和符号。 或者，可以使用写在盘表面的至少一个预定区域上的预定图案的实时数字分析来计算飞行高度变化的大小和符号。

公开(公告)号：US4821125A

公开(公告)日：1989-04-11

申请号：US872793

申请日：1986-06-11

申请人： Thomas C. Christensen ,  Jonathan D. Coker ,  Earl A. Cunningham ,  Richard C. Jaworski ,  Gregory J. Kerwin ,  Dean C. Palmer ,  Jeffrey R. Roepke

发明人： Thomas C. Christensen ,  Jonathan D. Coker ,  Earl A. Cunningham ,  Richard C. Jaworski ,  Gregory J. Kerwin ,  Dean C. Palmer ,  Jeffrey R. Roepke

IPC分类号： G11B5/09 ,  G11B5/00 ,  G11B5/012 ,  G11B5/035 ,  G11B5/455 ,  G11B20/18 ,  G11B27/36

CPC分类号： G11B20/10481 ,  G11B20/1816 ,  G11B27/36 ,  G11B5/012 ,  G11B5/455 ,  G11B2005/0013 ,  G11B2020/183 ,  G11B5/035

摘要： A magnetic disk drive channel circuitry is shown and described that generates eight incremental values of write current and eight incremental values of delta-V (the minimum voltage change per unit time which tests signals to discriminate between data and noise). Each of these variable parameter values may be program selected by a three bit bus signal. This variability testing of an adaptation to the optimum parameter value for each head media combination and by grouping tracks in contiguous data bands, the parameters may be optimized for tracks near the inner diameter, the outer diameter and in the middle band. The variable delta-V can also be used as an additional data recovery tool wherein re-reading with a lower value enhances recovery of missing bit errors and re-reading with an increased value can assist recovery from an extra bit error.

摘要翻译： 显示和描述了磁盘驱动器通道电路，其产生写入电流的八个增量值和delta-V的八个增量值（每单位时间的最小电压变化，其测试信号以区分数据和噪声）。 这些可变参数值中的每一个可以由三位总线信号来选择程序。 对于每个头部介质组合的最佳参数值的适应性以及通过对连续的数据带中的轨道进行分组的这种可变性测试，可以针对靠近内径，外径和中间带的轨迹优化参数。 变量delta-V也可以用作额外的数据恢复工具，其中用较低值重新读取增强了丢失位错误的恢复，并且用增加的值重新读取可以帮助从额外的位错误中恢复。

公开(公告)号：US5233482A

公开(公告)日：1993-08-03

申请号：US739020

申请日：1991-07-31

申请人： Richard L. Galbraith ,  Gregory J. Kerwin ,  Joey M. Poss

发明人： Richard L. Galbraith ,  Gregory J. Kerwin ,  Joey M. Poss

IPC分类号： G06F3/06 ,  G11B5/02 ,  G11B5/09 ,  G11B19/04 ,  G11B20/10 ,  G11B20/18 ,  G11B20/24

CPC分类号： G11B20/10009 ,  G11B19/04 ,  G11B20/18 ,  G11B20/24 ,  G11B5/6076

摘要： Apparatus and method of thermal asperity compensation are provided for data detection in a partial-response maximum-likelihood (PRML) data channel. The PRML data channel includes an analog to digital converter (ADC) having a normal operating range and a filter, gain and timing control coupled to the ADC. When a thermal asperity is detected, a thermal asperity recovery mode is established responsive to the detected thermal asperity. The gain and timing control are held and the normal operating range of the ADC is adjusted responsive to the thermal asperity recovery mode. Also an AC coupling pole frequency is elevated responsive to the thermal asperity recovery mode.

摘要翻译： 为部分响应最大似然（PRML）数据通道中的数据检测提供了热粗糙度补偿的装置和方法。 PRML数据通道包括具有正常操作范围的模数转换器（ADC）和耦合到ADC的滤波器，增益和定时控制。 当检测到热粗糙度时，响应于检测到的热不均匀性而建立热凹凸恢复模式。 保持增益和时序控制，并根据热凹凸恢复模式调整ADC的正常工作范围。 响应于热凹凸恢复模式，AC耦合极点频率也升高。

公开(公告)号：US5121263A

公开(公告)日：1992-06-09

申请号：US429750

申请日：1989-10-31

申请人： Gregory J. Kerwin ,  James W. Rae

发明人： Gregory J. Kerwin ,  James W. Rae

IPC分类号： G11B20/10 ,  G11B20/18 ,  G11B27/36

CPC分类号： G11B20/10055 ,  G11B20/10009 ,  G11B20/1816 ,  G11B27/36

摘要： In a disk drive providing amplitude sampling data detection, the amplitude of an analog read back signal is sampled at data clock intervals. The resulting analog values are converted to digital equivalent values. The digital equivalent values are each compared to an expected digital values that is representative of the data that was originally recorded on the disk, to thereby generate a different value. The resulting collection of difference values are magnitude segregated, and then stored in a plurality of registers, for later use in providing a histogram that is a measure of the disk drive's read error rate.

公开(公告)号：US5412518A

公开(公告)日：1995-05-02

申请号：US168630

申请日：1993-12-16

申请人： Jodie A. Christner ,  Earl A. Cunningham ,  Gregory J. Kerwin ,  Joe M. Poss

发明人： Jodie A. Christner ,  Earl A. Cunningham ,  Gregory J. Kerwin ,  Joe M. Poss

IPC分类号： G11B5/39 ,  G11B5/00 ,  G11B5/012 ,  G11B5/02 ,  G11B5/035 ,  G11B5/465 ,  G11B19/02 ,  G11B5/09

CPC分类号： G11B19/02 ,  G11B5/012 ,  G11B5/02 ,  G11B5/035 ,  G11B2005/0008 ,  G11B2005/0018 ,  G11B5/465

摘要： A method and apparatus is disclosed for adaptively controlling the biasing current applied to magnetoresistive (MR) read heads within a magnetic disk drive to provide optimized bias for each head/disk/channel component combination. An optimized bias current for each head is ascertained and stored on the disk surface at the time of manufacture. During each power up operation the values are transferred to random access memory which is accessed during the execution of each head switch command to apply bias current in accordance with the optimized value to the active MR head. Periodic reoptimization and updating of the stored values is effected by general error measurement circuitry that forms a part of the device control system and is invoked to perform the reoptimization upon the occurrence of an event such as a predetermined duration of power on operation subsequent to the last reoptimization procedure.

摘要翻译： 公开了一种用于自适应地控制施加到磁盘驱动器内的磁阻（MR）读取头的偏置电流的方法和装置，以为每个磁头/磁盘/通道组件组合提供优化的偏置。 在制造时，确定每个头部优化的偏置电流并将其存储在盘表面上。 在每个上电操作期间，这些值被传送到随机存取存储器，随机存取存储器是在执行每个磁头开关命令期间被访问的，以根据优化的值向偏置电流施加偏置电流。 存储值的定期重新优化和更新由构成设备控制系统的一部分的一般误差测量电路实现，并且被调用以在事件发生之后执行重新优化，例如在最后一个之后的预定的上电周期 重新优化程序。