Patents by Inventor Sundeep Chauhan
Sundeep Chauhan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 9905259Abstract: Provided herein is a method, including forming a first template including a first pattern, wherein forming the first template includes self-assembly of diblock copolymers guided by an initial pattern; forming a second template including a second pattern, wherein the second pattern corresponds to a servo pattern; and forming a master template from the first template, wherein the master template includes one or more portions of the first pattern combined with the second pattern.Type: GrantFiled: April 29, 2015Date of Patent: February 27, 2018Assignee: Seagate Technology LLCInventors: Sundeep Chauhan, Alexander Kantorov, Kim Yang Lee, David Kuo, Rene Johannes Marinus Van de Veerdonk, Barmeshwar Vikaramaditya
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Publication number: 20150302881Abstract: Provided herein is a method, including forming a first template including a first pattern, wherein forming the first template includes self-assembly of diblock copolymers guided by an initial pattern; forming a second template including a second pattern, wherein the second pattern corresponds to a servo pattern; and forming a master template from the first template, wherein the master template includes one or more portions of the first pattern combined with the second pattern.Type: ApplicationFiled: April 29, 2015Publication date: October 22, 2015Inventors: Sundeep Chauhan, Alexander Kantorov, Kim Yang Lee, David Kuo, Rene Johannes Marinus Van de Veerdonk, Barmeshwar Vikaramaditya
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Patent number: 8824092Abstract: The relative trajectory of a transducer head over bit-patterned media (BPM) may be skewed with respect to a down-track direction on the media (i.e., skew error). In order to resolve the skew error, the presently disclosed technology measures the skew error without adding additional patterning on the media. A detector circuit detects a sequential series of data bits on a storage media. The sequential series of data bits alternate between at least two tracks on the storage media. The sequential series of data bits are sent to a timing circuit, which sets a time stamp indicating when each data bit is received using, for example, a delay chain or a voltage ramp. A time elapsed between receiving a first data bit, a second data bit, and a third data bit is tracked. Transducer head skew is adjusted based on a signal containing the time elapsed between the bits.Type: GrantFiled: November 8, 2010Date of Patent: September 2, 2014Assignee: Seagate Technology LLCInventors: Sundeep Chauhan, Barmeshwar Vikramaditya
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Patent number: 8737001Abstract: A magnetic storage medium comprises a plurality of discrete magnetic elements and first and second adjoining servo sectors. Each of the servo sectors comprises first and second rows of the discrete magnetic elements extending in a track direction. The second row of the discrete magnetic elements are stacked relative to the discrete magnetic elements of the first row in a cross-track direction that is perpendicular to the track direction. The discrete magnetic elements of the first servo sector are staggered in the cross-track direction relative to the discrete magnetic elements of the second servo sector.Type: GrantFiled: September 15, 2010Date of Patent: May 27, 2014Assignee: Seagate Technology LLCInventors: Sundeep Chauhan, Mehmet Fatih Erden, Alexei H. Sacks, Qiang Ling
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Patent number: 8719616Abstract: A method for encoder frequency-shift compensation includes determining frequency values of an input encoder signal, determining repeatable frequency-shifts of the frequency values and generating a frequency-shift compensated clock using the repeatable frequency-shifts. A frequency-shift compensated clock includes a synthesizer configured to generate a frequency-shift compensated clock signal using repeatable frequency shifts and encoder clock signals.Type: GrantFiled: February 22, 2013Date of Patent: May 6, 2014Assignee: Seagate Technology LLCInventors: Koichi Wago, Sundeep Chauhan, David M. Tung
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Patent number: 8402303Abstract: The embodiments disclose a method for encoder frequency-shift compensation, including, determining frequency values of an input encoder signal, analyzing an encoder index clock signal and the input encoder signal to determine values of frequency-shifts and compensating for the values of the frequency-shifts to generate a frequency-shift compensated clock.Type: GrantFiled: April 29, 2011Date of Patent: March 19, 2013Assignee: Seagate Technology LLCInventors: Koichi Wago, Sundeep Chauhan, David M. Tung
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Publication number: 20120273999Abstract: The embodiments disclose a method for patterning a stack, including embedding servo patterns within a final template and creating positions of plural cross-tracked shifted position error signal (PES) fields incrementally from the embedded servo patterns on the final template.Type: ApplicationFiled: April 29, 2011Publication date: November 1, 2012Applicant: SEAGATE TECHNOLOGY, LLCInventors: Sundeep Chauhan, Alexander Kantorov, Kim Yang Lee, David Kuo, René Johannes Marinus Van de Veerdonk, Barmeshwar Vikramaditya
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Publication number: 20120274371Abstract: The embodiments disclose a method for encoder frequency-shift compensation, including, determining frequency values of an input encoder signal, analyzing an encoder index clock signal and the input encoder signal to determine values of frequency-shifts and compensating for the values of the frequency-shifts to generate a frequency-shift compensated clock.Type: ApplicationFiled: April 29, 2011Publication date: November 1, 2012Applicant: SEAGATE TECHNOLOGY, LLCInventors: Koichi Wago, Sundeep Chauhan, David M. Tung
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Publication number: 20120113539Abstract: The relative trajectory of a transducer head over bit-patterned media (BPM) may be skewed with respect to a down-track direction on the media (i.e., skew error). In order to resolve the skew error, the presently disclosed technology measures the skew error without adding additional patterning on the media. A detector circuit detects a sequential series of data bits on a storage media. The sequential series of data bits alternate between at least two tracks on the storage media. The sequential series of data bits are sent to a timing circuit, which sets a time stamp indicating when each data bit is received using, for example, a delay chain or a voltage ramp. A time elapsed between receiving a first data bit, a second data bit, and a third data bit is tracked. Transducer head skew is adjusted based on a signal containing the time elapsed between the bits.Type: ApplicationFiled: November 8, 2010Publication date: May 10, 2012Applicant: Seagate Technology LLCInventors: Sundeep Chauhan, Barmeshwar Vikramaditya
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Publication number: 20120063027Abstract: A magnetic storage medium comprises a plurality of discrete magnetic elements and first and second adjoining servo sectors. Each of the servo sectors comprises first and second rows of the discrete magnetic elements extending in a track direction. The second row of the discrete magnetic elements are stacked relative to the discrete magnetic elements of the first row in a cross-track direction that is perpendicular to the track direction. The discrete magnetic elements of the first servo sector are staggered in the cross-track direction relative to the discrete magnetic elements of the second servo sector.Type: ApplicationFiled: September 15, 2010Publication date: March 15, 2012Applicant: SEAGATE TECHNOLOGY LLCInventors: Sundeep Chauhan, Mehmet Fatih Erden, Alexei H. Sacks, Qiang Ling
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Publication number: 20110292546Abstract: A patterned recording media is formed from a master template that includes a data area and a timing track area having a final timing track. In order to form the final timing track, a first timing track is etched into master template and tested for accuracy by comparing the angular position of the master template to the timing track. If errors are detected in the timing track, the errors are used to create additional timing tracks which are etched into the master template. This process of improving the timing track is repeated until a final timing track is formed that has errors below a predetermined level. The timing tracks formed prior to the final timing track are removed and the master template is used to make stampers which are used to make patterned media disks.Type: ApplicationFiled: May 25, 2010Publication date: December 1, 2011Applicant: Seagate Technology LLCInventors: Dave Marcus Tung, Sundeep Chauhan, David Kuo, Shih-Fu Lee
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Patent number: 8045282Abstract: The eccentricity of tracks defined on a rotating bit patterned media are measured using a readback signal, and the measured eccentricity may be used to control centering of the disk relative to a rotational spindle and/or to control movement of a read/write head relative to a selected track on the disk.Type: GrantFiled: February 3, 2009Date of Patent: October 25, 2011Assignee: Seagate Technology LLCInventors: Barmeshwar Vikramaditya, Sundeep Chauhan, Patrick John Korkowski
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Publication number: 20110199285Abstract: A method for displaying waveform data may compress and transfer a large collection of data (e.g., a waveform) acquired from a device onto a screen without compromising any major features of the waveform. Waveform data maybe acquired with a data acquisition instrument. The acquisition instrument may perform in-line calculations to produce two-point sets from the data. The two-point sets may be transferred through an interface bus. The two-point sets may then be displayed as representations of the waveform data as vertical lines of pixels.Type: ApplicationFiled: October 4, 2010Publication date: August 18, 2011Inventors: Alexander Kantorov, Sundeep Chauhan
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Patent number: 7957084Abstract: Extracting transducer position information from bit patterned magnetic media includes providing a magnetic storage medium having at least one data array with multiple discrete and separated recording bits and providing the transducer adjacent the data array. A readback signal dependent upon the multiple recording bits is generated with the transducer. Determining the transducer position information further includes generating at least a first position signal and a second position signal from the readback signal.Type: GrantFiled: February 4, 2008Date of Patent: June 7, 2011Assignee: Seagate Technology LLCInventors: Sundeep Chauhan, Barmeshwar Vikramaditya
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Publication number: 20110051286Abstract: A recordable magnetic media includes a servo pattern having a plurality of adjacent alternating magnetic and nonmagnetic material stripes. At least some of the magnetic material stripes have magnetic transitions that define encoded data.Type: ApplicationFiled: September 1, 2009Publication date: March 3, 2011Applicant: SEAGATE TECHNOLOGY LLCInventors: PUSKAL PRASAD POKHAREL, MUSTAFA CAN OZTURK, BARMESHWAR WIKRAMADITYA, ALEXEI H. SACKS, SUNDEEP CHAUHAN, DAVID SHIAO-MIN KUO
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Patent number: 7839178Abstract: An apparatus and method for detecting a phase difference between an input signal and a reference signal in an all-digital phase locked loop (PLL) are provided. In a preferred embodiment, an N-stage tapped delay line and N-bit parallel latch are used to create a snapshot of the input signal by latching the output of the tapped delay line using the reference signal to clock the latch. An edge detector and encoder circuit translate the latched snapshot into a numerical phase difference value. A difference between this phase difference value and a desired phase difference is calculated and then added to an accumulator. The result in the accumulator is a numerical phase error value that can be fed to a numerically controlled oscillator (NCO). The output of the NCO can, in turn, be fed back into the phase/frequency comparator as the input signal, thus forming a fully-digital PLL.Type: GrantFiled: July 23, 2003Date of Patent: November 23, 2010Assignee: Seagate Technology LLCInventor: Sundeep Chauhan
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Publication number: 20100276390Abstract: A method of producing bit-patterned media master is provided whereby down-track and cross-track deflection plates are used to position an electronic beam at two (or more) adjacent tracks during the same revolution. Adjacent tracks of a bit-patterned media can be mastered simultaneously in the present invention by keeping the electronic beam ON during the entire time that the master is being created and the deflection plates are used to quickly ping-pong the electronic beam between the two (or more) adjacent tracks.Type: ApplicationFiled: May 1, 2009Publication date: November 4, 2010Applicant: Seagate Technology LLCInventors: Sundeep CHAUHAN, David Kuo, Kim Yang Lee
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Publication number: 20100195235Abstract: The eccentricity of tracks defined on a rotating bit patterned media are measured using a readback signal, and the measured eccentricity may be used to control centering of the disk relative to a rotational spindle and/or to control movement of a read/write head relative to a selected track on the disk.Type: ApplicationFiled: February 3, 2009Publication date: August 5, 2010Inventors: Barmeshwar Vikramaditya, Sundeep Chauhan, Patrick John Korkowski
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Patent number: 7706092Abstract: A patterned recording media comprises a segment and a null pattern formed in the segment. The segment comprises first and second rows of discrete magnetic elements separated by a non-magnetic material, and a row of non-magnetic material positioned between the first and second rows. The null pattern comprises consecutive groups of the discrete magnetic elements in the first and second rows of the segment. Each group in the first row has a magnetic polarity that is opposite the magnetic polarity of adjoining groups in the first row. Each group in the second row has a magnetic polarity that is opposite the magnetic polarity of adjoining groups in the second row.Type: GrantFiled: September 12, 2007Date of Patent: April 27, 2010Assignee: Seagate Technology LLCInventors: Qiang Ling, Mehmet Fatih Erden, Alexei H. Sacks, Sundeep Chauhan
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Publication number: 20090195916Abstract: Extracting transducer position information from bit patterned magnetic media includes providing a magnetic storage medium having at least one data array with multiple discrete and separated recording bits and providing the transducer adjacent the data array. A readback signal dependent upon the multiple recording bits is generated with the transducer. Determining the transducer position information further includes generating at least a first position signal and a second position signal from the readback signal.Type: ApplicationFiled: February 4, 2008Publication date: August 6, 2009Applicant: SEAGATE TECHNOLOGY LLCInventors: Sundeep Chauhan, Barmeshwar Vikramaditya