Lsi Corporation

Avago Technologies General IP (singapore) Pte. Ltd.

Avago Technologies International Sales Pte. Limited

Jefferson E Singleton

Shaohua Yang

George Mathew

Bruce Alexander Wilson

Jeffrey Paul Grundvig

Hongwei Song

Johnson Yen

Yuan Xing Lee

Richard Rauschmayer

Scott M Dziak

David Matthew Springberg

Kurt J Worrell

Fan Zhang

Erich Franz Haratsch

Shu Li

Jun Xiao

Changyou Xu

Jongseung Park

Peter John Windler

Jason D Byrne

David G Springberg

Madhusudan Kalluri

Kripa Venkatachalam

Keenan Terrell O'Brien

A data processing system is disclosed including a data detector, a data decoder and an alignment detector. The data detector is operable to apply a data detection algorithm to generate detected values for a data sector. The data decoder is operable to apply a data decode algorithm to a decoder input derived from the detected values to yield decoded values. The alignment detector is operable to calculate an offset between multiple versions of the data sector by correlating the multiple versions.

Systems and methods for correlation based data alignment

An apparatus for reading data from a magnetic storage medium includes a plurality of magnetic read heads each configured to read a track of the magnetic storage medium and generate an analog data signal corresponding to the read track. The apparatus includes a converter to generate digital data samples from the analog data signals, and a plurality of equalizers to apply a plurality of coefficients to the digital data samples to generate a plurality of equalized signals. The plurality of coefficients are associated with different locations within the track. The apparatus includes a plurality of detectors to compute metrics and detect data bits for the plurality of equalized signals, and at least one selector to select one of the plurality of equalized signals that has a best metric from the computed metrics and to output the selected equalized signal.

Devices and methods for reading magnetic media

Systems and methods relating generally to determining flaws on a storage medium.

Systems and methods for flaw scan with interleaved sectors

A data processing system includes a data input configured to receive input blocks of data, a memory configured to store the input blocks of data, a data processor configured to process the input blocks of data and to yield corresponding processed output blocks of data and a scheduler configured to cause the data processor to output the output blocks of data after a processing criterion has been met in the data processor. The memory is configured to retain the input blocks of data for reprocessing after the corresponding processed output blocks of data have been output from the data processor. The scheduler includes a control input configured to receive reprocessing requests for the retained input blocks of data. The scheduler is configured to initiate a reprocessing operation in the data processor for the retained blocks of data when the reprocessing requests are received on the control input.

Data processing system with retained sector reprocessing

Systems and method relating generally to data processing, and more particularly to systems and methods for segmenting a data set and recovering the segmented data set. In one particular example, a method is disclosed that includes: querying an input data set for an actual sync mark; forcing a proxy sync mark where the actual sync mark is not found in the input data set; applying data processing to the input data set to yield a processed output; correlating a potion of the processed output with a corresponding portion of the input data set to yield a true sync location; calculating a difference between the true sync location and the location of the forced sync mark to yield an offset; re-forcing the proxy sync mark based upon the offset; and re-applying the data processing to the input data set aligned using the re-forced proxy sync mark to yield a re-processed output.

Systems and methods for lost synchronization data set reprocessing

A method for producing a LDPC encoded test pattern for media in a LDPC based drive system includes adding error detection code data to a predominantly zero bit test pattern and adding additional zero bits to produce a test pattern of a desirable length. The test pattern may then be scrambled to produce a desirable flaw detection test pattern. The flaw detection test pattern may then be encoding with an LDPC code, or other error correction code with minimal disturbance to the run length constraints of the data pattern, and written to a storage medium.

Test pattern optimization for LDPC based flawscan

Data processing systems, circuits and methods are disclosed. As one example, a data processing system is disclosed that includes: a buffer circuit, a data processing circuit, and an erasure window set circuit. The buffer circuit is operable to store a data set as a buffered data set, and the data processing circuit is operable to repeatedly apply a data processing algorithm to the buffered data set. The erasure window set circuit is operable to define a location of the erasure window in relation to the buffered data set.

Systems and methods for rapid erasure retry decoding

A system and method for power management in a hard disk drive (HDD) assembly incorporating two or more read sensors includes directing a read/write head to follow a track; depowering one or more read sensors and readpath circuits associated with the read sensors; reading an analog readback signal through the first read sensor; processing the signal through an analog front-end to generate an input signal; sampling the input signal through an analog to digital converter at a first frequency to generate a first sampling signal; sampling the input signal through a second analog to digital converter at a second frequency to generate a second sampling signal; and generating a digital output signal from either or both sampling signals at a third sampling frequency through a digital signal processor. The method may additionally comprise adjusting a sampling frequency when power level reaches a threshold.

System and method for power saving modes in multi-sensor magnetic recording

An apparatus for detecting media flaws includes an envelope based media defect detector operable to identify a media defect based on an envelope of an input signal, a periodic pattern detector operable to determine whether the input signal comprises a data pattern, and a media flaw signal generation circuit operable to indicate a media defect when the envelope based media defect detector identifies the media defect and the periodic pattern detector determines that the input signal does not comprise the data pattern.

Systems and methods for media defect detection with pattern qualification

Hardware-based methods and apparatus are provided for inter-track interference mitigation in magnetic recording systems. Inter-track interference (ITI) is mitigated in a magnetic recording system by obtaining ITI cancellation data; and providing the ITI cancellation data to an ITI mitigation circuit using a write data path in the magnetic recording system. The write data path can optionally operate substantially simultaneously with the read data path performing the read operation. The ITI cancellation data comprises, for example, user data and/or media data.

Hardware-based methods and apparatus for inter-track interference mitigation in magnetic recording systems

Systems, methods, devices, circuits for data processing, and more particularly to data processing including operational marginalization capability.

Systems and methods for managed operational marginalization

Various embodiments of the present inventions provide systems and methods for data processing with out of order transfer. For example, a data processing system is disclosed that includes a data processor operable to process input blocks of data and to yield corresponding processed output blocks of data, wherein the processed output blocks of data are output from the data processor in an order in which their processing is completed, and a scheduler operable to receive processing priority requests for the input blocks of data and to assign processing resources in the data processor according to the priority requests.

Data processing system with out of order transfer

A hard disk drive or other disk-based storage device comprises a storage disk, a read/write head configured to read data from and write data to the storage disk, and control circuitry coupled to the read/write head and configured to process data received from and supplied to the read/write head and to control positioning of the read/write head relative to the storage disk. The control circuitry comprises an inter-track interference detector configured to process a signal read from at least a given track of the storage disk via the read/write head in order to detect interference in that signal from at least one other track of the storage disk. The control circuitry further comprises an inter-track interference based head position controller configured to adjust the positioning of the read/write head responsive to the detected interference.

Disk-based storage device with head position control responsive to detected inter-track interference

A hard disk drive or other disk-based storage device comprises a storage disk, a read/write head configured to read data from and write data to the storage disk, and control circuitry coupled to the read/write head and configured to process data received from and supplied to the read/write head and to control positioning of the read/write head relative to the storage disk. The control circuitry comprises a disk controller and read channel circuitry, with the read channel circuitry comprising a read channel memory. The control circuitry is further configured to selectively permit the disk controller to access the read channel memory. For example, the disk controller may be permitted to access the read channel memory only when the read channel circuitry is not performing a read operation.

Disk-based storage device having read channel memory that is selectively accessible to disk controller

Various embodiments of the present invention provide systems and methods for data processing. As an example, a data processing circuit is discussed that includes: a servo address mark count circuit, a user sync mark count circuit, and an offset calculation circuit. The servo address mark count circuit is operable to provide: a first count corresponding to a first servo address mark within a first track of a storage medium, a second count corresponding to a second servo address mark within the first track, a third count corresponding to a third servo address mark within a second track of the storage medium, and a fourth count corresponding to a fourth servo address mark within the second track. The user sync mark count circuit is operable to provide: a fifth count corresponding to a first user sync mark within the first track, and to provide a sixth count corresponding to a second user sync mark within the second track. The offset calculation circuit is operable to calculate an offset between the first track and the second track based at least in part on the first count, the second count, the third count, the fourth count, the fifth count, and the sixth count.

Growing community of inventors

Westminster, CO, United States of America

Jefferson E Singleton