Patents by Inventor Shashi KIRAN

Shashi KIRAN 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).

  • Patent number: 8825945
    Abstract: The present disclosure includes systems and techniques relating to non-volatile memory. A described system, for example, includes a non-volatile memory structure having a plurality of multi-level memory cells, a processing device, and a controller. The controller is configured to map a first portion of a first set of consecutive bits of a data segment to a first page associated with the plurality of multi-level memory cells, and map a second portion of the first set of consecutive bits of the data segment to a second page associated with the plurality of multi-level memory cells. The first page is associated with bits of a first significance, and the second page is associated with bits of a second significance.
    Type: Grant
    Filed: January 27, 2012
    Date of Patent: September 2, 2014
    Assignee: Marvell World Trade Ltd.
    Inventors: Shashi Kiran Chilappagari, Xueshi Yang, Gregory Burd
  • Publication number: 20140229792
    Abstract: Systems and methods are provided for decoding data. A decoder receives a variable node value and reliability data for a variable node, and check node values for check nodes associated with the variable node. Circuitry generates an updated variable node value, based on the received reliability data and the received check node values. The circuitry also generates, for at least one check node, an updated check node value based on the updated variable node value.
    Type: Application
    Filed: February 4, 2014
    Publication date: August 14, 2014
    Applicant: Marvell World Trade Ltd.
    Inventors: Nedeljko Varnica, Dung Viet Nguyen, Shashi Kiran Chilappagari
  • Publication number: 20140214302
    Abstract: Various methods and systems are provided for diagnosing the position and function of a valve in an engine system. In one embodiment, a method for an engine comprises determining a position of a valve in an engine system based on a turbine speed response upon commanded actuation of the valve.
    Type: Application
    Filed: January 29, 2013
    Publication date: July 31, 2014
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Chirag Bipinchandra Parikh, Shashi Kiran, Eric David Peters
  • Publication number: 20140160855
    Abstract: Systems and methods are provided to generate soft information related to the threshold voltage of a memory cell. A range of threshold voltages for the memory cell is divided into subregions of threshold voltage values herein referred to as bins. An output of the memory cell in response to an applied reference signal is measured. The applied reference signal includes a voltage value and position information. A single bin is identified based on the position information of the reference signal. The identified bin is split into more than one bin based on the output of the memory cell and the voltage value of the reference signal. The newly split bins and all the other bins that were not split are assigned new bin indices.
    Type: Application
    Filed: February 11, 2014
    Publication date: June 12, 2014
    Applicant: MARVELL WORLD TRADE LTD.
    Inventors: Zhengang Chen, Gregory Burd, Shashi Kiran Chilappagari, Xueshi Yang
  • Patent number: 8694868
    Abstract: Systems and methods are provided for decoding data using hard decisions and soft information. In particular, the systems and methods described herein are directed to decoders having variable nodes and check nodes, each with multiple states. The systems and methods include receiving, at a decoder during a first iteration, values for each of a plurality of variable nodes, and determining, during a second iteration, one or more indications for each of a plurality of check nodes based on the one or more values of the variable nodes received during the first iteration. The methods further include updating, at the decoder during the second iteration, the values for each of the variable nodes based on the values of the respective variable node received during the first iteration, and the indications for each of the plurality connected check nodes during the first iteration.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: April 8, 2014
    Assignee: Marvell International Ltd.
    Inventors: Shashi Kiran Chilappagari, Nedeljko Varnica, Xueshi Yang, Gregory Burd
  • Patent number: 8681564
    Abstract: Systems and methods are provided to generate soft information related to the threshold voltage of a memory cell. A range of threshold voltages for the memory cell is divided into subregions of threshold voltage values herein referred to as bins. An output of the memory cell in response to an applied reference signal is measured. The applied reference signal includes a voltage value and position information. A single bin is identified based on the position information of the reference signal. The identified bin is split into more than one bin based on the output of the memory cell and the voltage value of the reference signal. The newly split bins and all the other bins that were not split are assigned new bin indices.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: March 25, 2014
    Assignee: Marvell World Trade Ltd.
    Inventors: Zhengang Chen, Gregory Burd, Shashi Kiran Chilappagari, Xueshi Yang
  • Publication number: 20140068393
    Abstract: Systems and methods are provided for decoding data. A decoder retrieves data related to a symbol and identifies a plurality of candidate values for the symbol. The decoder determines a distance between each of the plurality of candidate values and a reference value associated with the symbol to obtain a plurality of distances, and the decoder determines whether to update a value of the symbol based at least in part on the plurality of distances.
    Type: Application
    Filed: August 23, 2013
    Publication date: March 6, 2014
    Applicant: MARVELL WORLD TRADE LTD.
    Inventors: Nedeljko Varnica, Shashi Kiran Chilappagari
  • Patent number: 8667361
    Abstract: Systems and methods are provided for decoding data using hard decisions and erasures. Circuitry receives data from each of a plurality of variable nodes which correspond to bits of data being decoded. Each variable node stores one of at least three values. The circuitry determines processes the values received from the plurality of variable nodes according to a set of processing rules. The processing rules are used to determine a condition related to the values stored by the plurality of variable nodes. The circuitry stores an indication of the stored condition at a check node.
    Type: Grant
    Filed: October 19, 2011
    Date of Patent: March 4, 2014
    Assignee: Marvell International Ltd.
    Inventors: Nedeljko Varnica, Shashi Kiran Chilappagari, Gregory Burd
  • Publication number: 20140052360
    Abstract: Various injector cooling structures and related engine systems and methods are provided. In one example, an injector cooling structure includes a cooling channel defined by a cooling jacket of a turbine. A cooling bore is provided at least partially within the cooling jacket, with the cooling bore configured to receive a pintle of an injector. The cooling channel is configured to circulate coolant for cooling the injector.
    Type: Application
    Filed: August 20, 2012
    Publication date: February 20, 2014
    Inventors: James Edward Arner, John Patrick Dowell, Shashi Kiran, Alexis Gruschow, Milan Shah
  • Publication number: 20140010009
    Abstract: A system including a read module to perform a first read operation to determine a state of a memory cell, and in response to a first failure to decode data read from the memory cell, perform second and third read operations to determine the state of the memory cell. The memory cell has first and second threshold voltages when programmed to first and second states, respectively. A shift detection module detects, in response to a second failure to decode data read from the memory cell in the second and third read operations, a shift in a distribution of at least one of the first and second threshold voltages. A binning module divides the distribution into a plurality of bins. A log-likelihood ratio (LLR) module generates LLRs for the plurality of bins based on a variance of the distribution and adjusts the LLRs based on an amount of the shift.
    Type: Application
    Filed: September 9, 2013
    Publication date: January 9, 2014
    Applicant: Marvell World Trade Ltd.
    Inventors: Shashi Kiran Chilappagari, Xueshi Yang
  • Patent number: 8576625
    Abstract: An apparatus including a memory array and control circuitry. The control circuitry is configured to, based at least on a plurality of read comparison results, determine a number of memory cells of the memory array that have threshold voltages that fall into each of a plurality of voltage ranges. The control circuitry is further configured to, based at least on the number of memory cells that have threshold voltages in each of the plurality of voltage ranges, estimate an offset amount that a center voltage between two threshold voltage distributions differs from a center reference voltage. The control circuitry is further configured to read one or more of the plurality of memory cells based at least in part on the estimated offset amount.
    Type: Grant
    Filed: April 18, 2011
    Date of Patent: November 5, 2013
    Assignee: Marvell International Ltd.
    Inventors: Xueshi Yang, Shashi Kiran Chilappagari
  • Patent number: 8531888
    Abstract: A system including a reference voltage module to select a first reference voltage between a first threshold voltage corresponding to a first state of a memory cell and a second threshold voltage corresponding to a second state of the memory cell, a second reference voltage less than the first reference voltage, and a third reference voltage greater than the first reference voltage. The system includes a read module to perform a first read operation to determine a state of the memory cell based on the first reference voltage, and in response to a first failure to decode data read from the memory cell in the first read operation, perform a second read operation to determine the state based on the second reference voltage and a third read operation to determine the state based on the third reference voltage.
    Type: Grant
    Filed: June 24, 2011
    Date of Patent: September 10, 2013
    Assignee: Marvell World Trade Ltd.
    Inventors: Shashi Kiran Chilappagari, Xueshi Yang
  • Publication number: 20130186376
    Abstract: Various methods and systems are provided for diagnosing an engine component condition in an exhaust gas recirculation system. In one example, a method includes selectively routing exhaust from a subset of engine cylinders to an exhaust passage via a first valve and to an intake passage via a second valve, and obtaining one or more of a pressure or temperature from the subset of engine cylinders. The method further includes indicating an engine component condition based on the one or more of the pressure or temperature.
    Type: Application
    Filed: January 25, 2012
    Publication date: July 25, 2013
    Inventors: Eric David Peters, Shashi Kiran, Nicholas Hansen
  • Patent number: 8458556
    Abstract: In this invention, a new class of finite precision multilevel decoders for low-density parity-check (LDPC) codes is presented. These decoders are much lower in complexity compared to the standard belief propagation (BP) decoder. Messages utilized by these decoders are quantized to certain levels based on the number of bits allowed for representation in hardware. A message update function specifically defined as part of the invention, is used to determine the outgoing message at the variable node, and the simple min operation along with modulo 2 sum of signs is used at the check node. A general methodology is provided to obtain the multilevel decoders, which is based on reducing failures due to trapping sets and improving the guaranteed error-correction capability of a code. Hence these decoders improve the iterative decoding process on finite length graphs and have the potential to outperform the standard floating-point BP decoder in the error floor region.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: June 4, 2013
    Assignee: STMicroelectronics, SA
    Inventors: Shiva K. Planjery, Shashi Kiran Chilappagari, Bane Vasic, David Declercq
  • Publication number: 20130125524
    Abstract: Methods and systems are provided related to an emissions control system. The emissions control system has an exhaust after-treatment system defining a plurality of distinct exhaust flow passages through which at least a portion of an exhaust stream can flow, e.g., the exhaust stream is produced by an engine. The emissions control system also includes a controller for controlling injection of reductant into the exhaust stream flowing through each of the flow passages. In one example, the emissions control system is configured for use in a vehicle, such as a locomotive or other rail vehicle.
    Type: Application
    Filed: December 21, 2010
    Publication date: May 23, 2013
    Inventors: Jessica Lynn Plummer, Gail LeRoy Detar, Shashi Kiran, Shridhar Shrikant Kulkarni, Lawrence Heverley, III
  • Publication number: 20130067887
    Abstract: Various methods and systems are provided for a system for an engine. In one example, the system includes an exhaust passage through which exhaust gas is configured to flow from the engine. The system further includes an aftertreatment system disposed in the exhaust passage, the aftertreatment system including an aftertreatment device and a bypass with a bypass control element, the bypass control element adjustable to reduce exhaust gas flow through the aftertreatment device during tunneling operation.
    Type: Application
    Filed: September 20, 2011
    Publication date: March 21, 2013
    Inventors: Lawrence Hoey Heverley III, Shashi Kiran, Stephen Mark Geyer
  • Publication number: 20120317460
    Abstract: Embodiments provide a method comprising estimating a first set of log-likelihood ratio (LLR) values for a plurality of memory cells of a memory; based on the first set of LLR values, performing a first error correcting code (ECC) decoding operation; in response to determining a failure of the first ECC decoding operation, generating, by adjusting the first set of LLR values, a second set of LLR values for the plurality of memory cells; and based on the second set of LLR values, performing a second ECC decoding operation.
    Type: Application
    Filed: May 25, 2012
    Publication date: December 13, 2012
    Inventors: Shashi Kiran Chilappagari, Gregory Burd, Zhengang Chen
  • Publication number: 20120300545
    Abstract: Systems and methods are provided to generate soft information related to the threshold voltage of a memory cell. A range of threshold voltages for the memory cell is divided into subregions of threshold voltage values herein referred to as bins. An output of the memory cell in response to an applied reference signal is measured. The applied reference signal includes a voltage value and position information. A single bin is identified based on the position information of the reference signal. The identified bin is split into more than one bin based on the output of the memory cell and the voltage value of the reference signal. The newly split bins and all the other bins that were not split are assigned new bin indices.
    Type: Application
    Filed: May 22, 2012
    Publication date: November 29, 2012
    Applicant: E I DU PONT DE NEMOURS AND COMPANY
    Inventors: Zhengang Chen, Gregory Burd, Shashi Kiran Chilappagari, Xueshi Yang
  • Publication number: 20120279206
    Abstract: An exhaust gas treatment device includes a first substrate coated with a low temperature catalyst configured to facilitate formation of an oxidizer when an exhaust gas temperature is below a threshold temperature. The device further includes a second substrate coated with a high temperature catalyst and positioned coaxially with the first substrate, the high temperature catalyst configured to facilitate formation of the oxidizer when the exhaust gas temperature is above the threshold temperature.
    Type: Application
    Filed: August 25, 2011
    Publication date: November 8, 2012
    Inventors: STEPHEN MARK GEYER, Shashi Kiran, Paul Llovd Flynn
  • Publication number: 20120222659
    Abstract: Various methods and systems are provided for operating an exhaust gas recirculation engine having a plurality of exhaust gas donor cylinders and a plurality of non-donor cylinders. One example method includes firing each of the engine cylinders in a cylinder firing order, including firing at least one of the non-donor cylinders between every donor cylinder firing of the engine cycle.
    Type: Application
    Filed: March 3, 2011
    Publication date: September 6, 2012
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Sachin Shivajirao Kulkarni, Sebastian Walter Freund, Jassin Marcel Fritz, Georgios Bikas, James Henry Yager, Shashi Kiran