公开(公告)号：US09236081B1

公开(公告)日：2016-01-12

申请号：US14674360

申请日：2015-03-31

Applicant: Seagate Technology LLC

Inventor： Alfredo S. Chu ,  Jason W. Riddering ,  Drew M. Mader ,  Huazhou Lou ,  Pu-Ling Lu

IPC: G11B11/00 ,  G11B7/1267 ,  G11B11/105 ,  G11B7/1263 ,  G11B7/12 ,  G11B5/48 ,  G11B5/60

CPC classification number: G11B7/1263 ,  G11B5/012 ,  G11B5/455 ,  G11B5/4866 ,  G11B5/6088 ,  G11B11/10595 ,  G11B2005/0021

Abstract: A method includes setting a heat assisted magnetic recording (HAMR) device located in a data storage system having a laser to an operating temperature. A threshold laser current is determined. An optimal laser current is determined. The threshold laser current and the optimal laser current are stored in memory. The steps of determining a threshold laser current, determining an optimal laser current and storing the threshold laser current and the optimal laser current into the calibration table are repeated until acceptable device performance is achieved at more than one operating temperature.

Abstract translation: 一种方法包括将位于具有激光的数据存储系统中的热辅助磁记录（HAMR）装置设置到工作温度。 确定阈值激光电流。 确定最佳激光电流。 阈值激光电流和最佳激光电流存储在存储器中。 重复确定阈值激光电流，确定最佳激光电流并将阈值激光电流和最佳激光电流存储到校准表中的步骤，直到在多于一个工作温度下实现可接受的器件性能。

公开(公告)号：US11881239B1

公开(公告)日：2024-01-23

申请号：US17733521

申请日：2022-04-29

Applicant: Seagate Technology LLC

Inventor： Walter R. Eppler ,  Drew M. Mader

IPC: G11B21/02 ,  G11B5/60

CPC classification number: G11B5/6029

Abstract: A controller extracts a distortion component of a readback signal from a magnetic read head. The distortion component may be found using a finite length Volterra series, for example. The controller estimates a clearance between the read head and a recording medium based on the distortion component. This clearance measurement can be used for closed loop fly-height control of the read head.