公开(公告)号：US20050232018A1

公开(公告)日：2005-10-20

申请号：US11091352

申请日：2005-03-28

申请人： Daniel Dolan ,  James Howley ,  Zachary Keirn ,  German Feyh ,  Michael Straub

发明人： Daniel Dolan ,  James Howley ,  Zachary Keirn ,  German Feyh ,  Michael Straub

IPC分类号： G11B5/00 ,  G11B5/012 ,  G11B5/09 ,  G11B5/127 ,  G11B20/10 ,  G11C16/06

CPC分类号： G11B20/10203 ,  G11B5/012 ,  G11B5/09 ,  G11B5/1278 ,  G11B20/10009 ,  G11B20/1403 ,  G11B2005/001

摘要： User data is read from a medium having servo data and user data encoded thereon. The user data is read with a read/write head that is operable in a write mode and a read mode. Servo data is read in a time window following a transition from write mode to read mode, with a frequency passband that has a first low frequency corner. User data is read from the medium after expiration of the time window, with a frequency passband that has a second low frequency corner that is lower than the first low frequency corner.

摘要翻译： 从具有伺服数据和在其上编码的用户数据的介质读取用户数据。 读取/写入头可以在写入模式和读取模式下操作用户数据。 在从写入模式转换到读取模式之后的时间窗口中读取伺服数据，具有第一低频角的频率通带。 用户数据在时间窗口到期后从介质中读取，频率通带具有低于第一低频角的第二低频角。

公开(公告)号：US20060152838A1

公开(公告)日：2006-07-13

申请号：US11034997

申请日：2005-01-13

申请人： David Fitzgerald ,  Jeffrey Gleason ,  James Howley ,  Scott O'Brien ,  Michael Straub

发明人： David Fitzgerald ,  Jeffrey Gleason ,  James Howley ,  Scott O'Brien ,  Michael Straub

IPC分类号： G11B5/09

CPC分类号： G11B5/02 ,  G11B2005/001 ,  G11B2005/0018

摘要： A recording system employing a magneto-resistive (MR) element senses a resistance value of the MR element and generates one or more MR resistance (MRR) signal values based on the sensed MR element resistance value. The MRR signal values might be, for example, current or voltage values proportional or inversely proportional to the MR element resistance value. The MRR signal values might be employed to control one or more of: i) a unity gain bandwidth of a bias loop for the MR element, ii) an MR read head preamplifier low corner frequency, and iii) a slew rate across the MR element.

摘要翻译： 使用磁阻（MR）元件的记录系统感测MR元件的电阻值，并且基于感测的MR元件电阻值产生一个或多个MR电阻（MRR）信号值。 MRR信号值可以是例如与MR元件电阻值成比例或成反比的电流​​值或电压值。 可以采用MRR信号值来控制以下各项中的一个或多个：i）用于MR元件的偏置环路的单位增益带宽，ii）MR读取头前置放大器低转角频率，以及iii）横跨MR元件的转换速率 。

公开(公告)号：US20050254158A1

公开(公告)日：2005-11-17

申请号：US10955237

申请日：2004-09-30

申请人： Stephen Kuehne ,  James Howley ,  Che Leung ,  David Kelly

发明人： Stephen Kuehne ,  James Howley ,  Che Leung ,  David Kelly

IPC分类号： G11B5/02 ,  G11B5/11 ,  G11B5/40

CPC分类号： G11B5/02 ,  G11B5/11 ,  G11B5/40

摘要： Use of a depletion mode MOSFET to protect differential terminals of a disk drive read head transducer from an electrostatic discharge event, wherein MOSFET source and drain terminals are connected to the differential terminals. The MOSFET is normally “on” such that a conductive path is provided between the differential signal terminals during assembly of the transducer into a disk drive data storage system and during periods when the transducer is inoperative. The conductive path, limits the differential voltage between the terminals that is generated by a current pulse of an ESD event. The MOSFET is gated off during operation of the disk drive to permit a differential read signal, representing the read data bits, to be developed between the differential terminals.

摘要翻译： 使用耗尽型MOSFET来保护磁盘驱动器读头传感器的差动端子与静电放电事件，其中MOSFET源极和漏极端子连接到差分端子。 MOSFET通常“导通”，使得在将换能器组装到盘驱动器数据存储系统期间以及在换能器不工作的时段期间，在差分信号端子之间提供导电路径。 导电路径限制由ESD事件的电流脉冲产生的端子之间的差分电压。 在磁盘驱动器的操作期间，MOSFET被选通，以允许在差分端子之间形成表示读取数据位的差分读取信号。

公开(公告)号：US20050008050A1

公开(公告)日：2005-01-13

申请号：US10616334

申请日：2003-07-09

申请人： Jonathan Fischer ,  James Howley

发明人： Jonathan Fischer ,  James Howley

IPC分类号： H01S3/00 ,  H01S5/042 ,  H01S5/068 ,  H01S5/0683

CPC分类号： H01S5/0683 ,  H01S5/042 ,  H01S5/06812

摘要： The present invention provides a method and apparatus, such as an integrated circuit, to control the optical midpoint power level and the extinction ratio of a semiconductor laser and maintain the optical midpoint power level and the extinction ratio substantially constant at corresponding predetermined levels. Apparatus embodiments include a semiconductor laser, a modulator, a photodetector, an optical midpoint controller, and an extinction ratio controller. The semiconductor laser is capable of transmitting an optical signal in response to a modulation current. The modulator is capable of providing the modulation current to the semiconductor laser, with the modulation current corresponding to an input data signal. The photodetector, which is optically coupled to the semiconductor laser, is capable of converting the optical signal into a photodetector current. In response to the photodetector current, the optical midpoint controller is capable of adjusting the forward bias current of the semiconductor laser, and the extinction ratio controller is capable of adjusting the modulation current provided by the modulator to the semiconductor laser, to respectively generate the optical signal having substantially a predetermined optical midpoint power level and a predetermined extinction ratio.

摘要翻译： 本发明提供了一种诸如集成电路的方法和装置，用于控制半导体激光器的光中点功率电平和消光比，并将光中点功率电平和消光比保持在相应的预定电平上。 装置实施例包括半导体激光器，调制器，光电检测器，光中点控制器和消光比控制器。 半导体激光器能够响应于调制电流而发送光信号。 调制器能够向半导体激光器提供调制电流，调制电流对应于输入数据信号。 光学耦合到半导体激光器的光电检测器能够将光信号转换成光电检测器电流。 响应于光检测器电流，光中点控制器能够调节半导体激光器的正向偏置电流，并且消光比控制器能够调制由调制器提供给半导体激光器的调制电流，以分别产生光学 信号具有基本上预定的光中点功率电平和预定的消光比。

公开(公告)号：US20050008280A1

公开(公告)日：2005-01-13

申请号：US10616332

申请日：2003-07-09

申请人： James Howley

发明人： James Howley

IPC分类号： G02B6/00 ,  G02B6/12 ,  H01S5/026 ,  H01S5/062 ,  H01S5/0683

CPC分类号： H01S5/062 ,  H01S5/026 ,  H01S5/0264

摘要： The present invention provides a method and apparatus, such as an integrated circuit, to control the extinction ratio of a semiconductor laser and maintain the extinction ratio substantially constant at a predetermined level. Apparatus embodiments include a semiconductor laser, a modulator, a photodetector, and an extinction ratio controller. The semiconductor laser is capable of transmitting an optical signal in response to a modulation current. The modulator is capable of providing the modulation current to the semiconductor laser, with the modulation current corresponding to an input data signal. The photodetector, which is optically coupled to the semiconductor laser, is capable of converting the optical signal into a photodetector current. The extinction ratio controller, in response to the photodetector current, is capable of adjusting the modulation current provided by the modulator to the semiconductor laser to generate the optical signal having substantially a predetermined extinction ratio.

摘要翻译： 本发明提供了一种控制半导体激光器的消光比并将消光比保持在预定水平的方法和装置，例如集成电路。 装置实施例包括半导体激光器，调制器，光电检测器和消光比控制器。 半导体激光器能够响应于调制电流而发送光信号。 调制器能够向半导体激光器提供调制电流，调制电流对应于输入数据信号。 光学耦合到半导体激光器的光电检测器能够将光信号转换成光电检测器电流。 响应于光电检测器电流，消光比控制器能够将由调制器提供的调制电流调节到半导体激光器，以产生具有基本上预定消光比的光信号。