公开(公告)号：US09741378B1

公开(公告)日：2017-08-22

申请号：US15244564

申请日：2016-08-23

Applicant: Seagate Technology LLC

Inventor： Won Choul Yang

IPC: G11B11/00 ,  G11B5/48 ,  G11B5/00 ,  G11B7/126 ,  G11B11/105 ,  G11B7/1267 ,  G11B5/60

CPC classification number: G11B5/455 ,  G11B5/314 ,  G11B5/58 ,  G11B5/6088 ,  G11B7/126 ,  G11B7/1263 ,  G11B7/1267 ,  G11B11/10506 ,  G11B11/1051 ,  G11B20/182 ,  G11B2005/0021

Abstract: A method includes moving a heat-assisted magnetic recording head relative to a magnetic recording medium comprising a plurality of tracks, the head comprising a reader and a writer including a near-field transducer (NFT) optically coupled to a laser diode, the writer comprising a center which is laterally offset relative to a center of the reader to define a writer-reader offset (WRO) therebetween. Patterns are written to a particular track at a plurality of laser diode current levels. The patterns are read and a WRO value is calculated at a peak amplitude position for each of the laser diode current levels. A slope of the WRO values is determined with the laser current diode levels. A health condition of the NFT is determined by determining if the slope is greater than a predetermined threshold indicative of non-uniform activation across the NFT.

公开(公告)号：US09153272B1

公开(公告)日：2015-10-06

申请号：US14278386

申请日：2014-05-15

Applicant: Seagate Technology LLC

Inventor： Tim Rausch ,  Jon D. Trantham ,  John W. Dykes ,  Won Choul Yang

IPC: G11B11/00 ,  G11B7/1267 ,  G11B5/012 ,  G11B7/1263 ,  G11B5/00

CPC classification number: G11B7/1267 ,  G11B5/012 ,  G11B5/314 ,  G11B5/455 ,  G11B5/6088 ,  G11B7/1263 ,  G11B2005/0021

Abstract: At least one laser input current is applied to a laser in a heat assisted magnetic recording device. Laser output power of the laser is measured at the at least one applied laser current. A relationship is characterized amongst temperature, applied laser input current and laser output power. Laser current is set to an optimal laser current as determined at manufacturing. A metric of recording performance is measured to determine if the relationship is acceptable.

Abstract translation: 至少一个激光输入电流被施加到热辅助磁记录装置中的激光器。 在至少一个施加的激光电流下测量激光器的激光输出功率。 温度，施加的激光输入电流和激光输出功率之间的关系的特征。 激光电流设置为在制造时确定的最佳激光电流。 测量记录性能的度量以确定该关系是否可接受。

公开(公告)号：US09437234B1

公开(公告)日：2016-09-06

申请号：US14831314

申请日：2015-08-20

Applicant: Seagate Technology LLC

Inventor： Shi Jung Kim ,  Dong Wook Lee ,  Ju Yong Lee ,  Won Choul Yang

IPC: G11B5/60 ,  G11B7/1263 ,  G11B20/18 ,  G11B5/31 ,  G11B5/00

CPC classification number: G11B5/6076 ,  G11B5/3136 ,  G11B5/607 ,  G11B7/1263 ,  G11B20/18 ,  G11B2005/0021

Abstract: An apparatus comprises a read/write head having a heater, wherein a low- or non-modulation interface is defined between the head and a magnetic recording medium. A microactuator is coupled to the head. A main actuator is coupled to the microactuator and the head. A controller is coupled to the main actuator, the microactuator, and the head. The controller is configured to control movement of the main actuator and the microactuator in response to a position error signal. The controller is further configured to induce an oscillation in the heater at a predetermined frequency. A detector is coupled to the controller. The detector is configured to sense a disturbance in the PES supplied to the microactuator resulting from the induced heater oscillation, and detect contact between the head and the medium using the PES disturbance.

Abstract translation: 一种装置包括具有加热器的读/写头，其中在头和磁记录介质之间限定低调或非调制接口。 微型致动器耦合到头部。 主致动器联接到微致动器和头部。 控制器耦合到主致动器，微致动器和头。 控制器被配置为响应于位置误差信号来控制主致动器和微致动器的运动。 控制器还被配置为以预定频率诱发加热器中的振荡。 检测器耦合到控制器。 检测器被配置为感测由感应的加热器振荡产生的提供给微致动器的PES中的干扰，并使用PES干扰来检测头部和介质之间的接触。

公开(公告)号：US09355671B2

公开(公告)日：2016-05-31

申请号：US14278377

申请日：2014-05-15

Applicant: Seagate Technology LLC

Inventor： Tim Rausch ,  Jon D. Trantham ,  John W. Dykes ,  Won Choul Yang

IPC: G11B7/125 ,  G11B11/00 ,  G11B7/1267 ,  G11B7/1263 ,  G11B7/007 ,  G11B19/04

CPC classification number: G11B7/1263 ,  G11B5/012 ,  G11B5/02 ,  G11B7/00736 ,  G11B7/1267 ,  G11B19/046 ,  G11B2005/0021

Abstract: A method of controlling laser output in a heat assisted magnetic recording device can be performed by control circuitry in a data storage device. The method includes measuring a temperature, measuring laser output power of a laser, determining a power error by subtracting an optimal laser output power from the measured laser output power and comparing the power error to at least one threshold to determine whether an applied current to the laser needs to be adjusted. The at least one threshold is related to how great the power error can be while maintaining the integrity of data on a recording medium.

Abstract translation: 控制热辅助磁记录装置中的激光输出的方法可由数据存储装置中的控制电路执行。 该方法包括测量温度，测量激光器的激光输出功率，通过从所测量的激光输出功率减去最佳激光输出功率并将功率误差与至少一个阈值进行比较来确定功率误差，以确定施加到 激光需要调整。 至少一个阈值与维持记录介质上数据完整性的功率误差有多大关系。

公开(公告)号：US10043540B1

公开(公告)日：2018-08-07

申请号：US15667245

申请日：2017-08-02

Applicant: Seagate Technology LLC

Inventor： Won Choul Yang

IPC: G11B11/00 ,  G11B5/455 ,  G11B5/58 ,  G11B20/18 ,  G11B5/00 ,  G11B7/1263 ,  G11B7/1267 ,  G11B5/60 ,  G11B7/126

Abstract: A method includes moving a heat-assisted magnetic recording head relative to a magnetic recording medium comprising a plurality of tracks, the head comprising a reader and a writer including a near-field transducer (NFT) optically coupled to a laser diode, the writer comprising a center which is laterally offset relative to a center of the reader to define a writer-reader offset (WRO) therebetween. Patterns are written to a particular track at a plurality of laser diode current levels. The patterns are read and a WRO value is calculated at a peak amplitude position for each of the laser diode current levels. A slope of the WRO values is determined with the laser current diode levels. A health condition of the NFT is determined by determining if the slope is greater than a predetermined threshold indicative of non-uniform activation across the NFT.

公开(公告)号：US20160307590A1

公开(公告)日：2016-10-20

申请号：US14688049

申请日：2015-04-16

Applicant: Seagate Technology LLC

Inventor： Won Choul Yang ,  Shi Jung Kim ,  Ju Yong Lee

IPC: G11B7/1267

CPC classification number: G11B7/1267 ,  G11B5/02 ,  G11B5/3133 ,  G11B7/126 ,  G11B7/1263 ,  G11B2005/001 ,  G11B2005/0021

Abstract: A current temperature of a data storage device having a heat assisted recording (HAMR) device is measured while in idle. A threshold laser diode power output of the HAMR device is calculated at the current temperature when there is a change between a previous temperature and the current temperature. A new laser diode current that produced the calculated threshold laser diode power output is applied to the HAMR device when there is a change between the currently applied laser diode current and the new laser diode current.

Abstract translation: 在空闲状态下测量具有热辅助记录（HAMR）装置的数据存储装置的当前温度。 当在先前温度和当前温度之间存在变化时，在当前温度下计算HAMR器件的阈值激光二极管功率输出。 当激光二极管电流和新激光二极管电流之间发生变化时，产生计算出的阈值激光二极管功率输出的新型激光二极管电流被施加到HAMR器件。

公开(公告)号：US20140177089A1

公开(公告)日：2014-06-26

申请号：US13725054

申请日：2012-12-21

Applicant: SEAGATE TECHNOLOGY LLC

Inventor： Jung Wook Hur ,  Won Choul Yang ,  Haejung Lee

IPC: G11B5/455

CPC classification number: G11B5/455 ,  G11B5/607

Abstract: Technologies are described herein for recovering an instable head in a storage device using an internal head heater. An instability in the reader head may be detected, and, in response to detecting the instability, a thermal shock may be applied to the reader head utilizing the head heater to recover the head.

Abstract translation: 这里描述了用于使用内部头部加热器来恢复存储装置中的不稳定头部的技术。 可以检测读取器头部的不稳定性，并且响应于检测到不稳定性，可以利用头部加热器对读取头施加热冲击以恢复头部。

公开(公告)号：US09607642B1

公开(公告)日：2017-03-28

申请号：US15007728

申请日：2016-01-27

Applicant: Seagate Technology LLC

Inventor： Won Choul Yang ,  Jin Pil Kim ,  Shi Jung Kim

IPC: G11B5/60

CPC classification number: G11B5/6076 ,  G11B5/6035 ,  G11B5/607

Abstract: An AC signal having a specified frequency and a DC offset voltage is applied to a slider substrate or a magnetic recording medium. A low- or non-modulation interface is defined between the slider and medium. In response to applying the AC signal, an oscillation in an electrostatic force occurs between the slider and the medium at the specified frequency, which causes an oscillation in thermal sensor signal at the slider, which oscillates at the specified frequency. A heater of the slider is adjusted to decrease spacing between the slider and medium during oscillation of the electrostatic force. For each heater adjustment, thermal sensor resistance is measured over a specified number of medium revolutions. Head-medium contact is detected using one of an amplitude of a harmonic of the thermal sensor signal and a summation of amplitudes of all frequency components at the specified frequency.

公开(公告)号：US09472229B1

公开(公告)日：2016-10-18

申请号：US14688049

申请日：2015-04-16

Applicant: Seagate Technology LLC

Inventor： Won Choul Yang ,  Shi Jung Kim ,  Ju Yong Lee

IPC: G11B7/1263 ,  G11B7/126 ,  G11B7/1267 ,  G11B5/00

CPC classification number: G11B7/1267 ,  G11B5/02 ,  G11B5/3133 ,  G11B7/126 ,  G11B7/1263 ,  G11B2005/001 ,  G11B2005/0021

Abstract: A current temperature of a data storage device having a heat assisted recording (HAMR) device is measured while in idle. A threshold laser diode power output of the HAMR device is calculated at the current temperature when there is a change between a previous temperature and the current temperature. A new laser diode current that produced the calculated threshold laser diode power output is applied to the HAMR device when there is a change between the currently applied laser diode current and the new laser diode current.

Abstract translation: 在空闲状态下测量具有热辅助记录（HAMR）装置的数据存储装置的当前温度。 当在先前温度和当前温度之间存在变化时，在当前温度下计算HAMR器件的阈值激光二极管功率输出。 当激光二极管电流和新激光二极管电流之间发生变化时，产生计算出的阈值激光二极管功率输出的新型激光二极管电流被施加到HAMR器件。

公开(公告)号：US09245561B1

公开(公告)日：2016-01-26

申请号：US14666765

申请日：2015-03-24

Applicant: Seagate Technology LLC

Inventor： Ju Yong Lee ,  Won Choul Yang ,  Shi Jung Kim

IPC: G11B21/02 ,  G11B5/60

CPC classification number: G11B5/6017 ,  G11B5/607 ,  G11B5/6076

Abstract: An apparatus comprises a slider that includes a fly height sensor. A signal generator is coupled to the slider. The signal generator is configured to generate an AC electrical signal having a DC offset voltage and to adjust the DC offset of the AC electrical signal to a plurality of DC offset voltages. Circuitry is coupled to the fly height sensor and the signal generator. The circuitry is configured to measure fly height of the slider in response to application of the AC electrical signal with varying DC offset voltages to the slider. The circuitry is further configured to determine an extremum of the measured fly heights and generate an output that includes the DC offset voltage associated with the fly height extremum.

Abstract translation: 一种装置包括包括飞高传感器的滑块。 信号发生器耦合到滑块。 信号发生器被配置为产生具有DC偏移电压的AC电信号，并且将AC电信号的DC偏移调整到多个DC偏移电压。 电路耦合到飞行高度传感器和信号发生器。 电路被配置为响应于具有变化的DC偏移电压的AC电信号到滑块来测量滑块的飞行高度。 该电路还被配置成确定所测量的飞行高度的极值，并产生包括与飞行高度极值相关联的DC偏移电压的输出。