Patents by Inventor Uday Chandrasekhar

Uday Chandrasekhar 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: 10832766
    Abstract: An apparatus and/or system is described including a memory device or a controller to perform programming and verification operations including application of a shared voltage level to verify two program voltage levels of a multi-level cell device. For example, in embodiments, the control circuitry performs a program operation to program a memory cell and performs a verification operation by applying a single or shared verify voltage level to verify that the memory cell is programmed to a corresponding program voltage level. In embodiments, the program voltage level is one of two consecutive program voltage levels of a plurality of program voltage levels to be verified by application of the shared verify voltage. Other embodiments are disclosed and claimed.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: November 10, 2020
    Assignee: Intel Corporation
    Inventors: Ali Khakifirooz, Pranav Kalavade, Uday Chandrasekhar, Trupti Bemalkhedkar, Chang Wan Ha
  • Patent number: 10325665
    Abstract: A controller for a NAND memory array is presented. In embodiments, the controller may include circuitry to provide bias voltages to a NAND memory array that includes two or more decks of memory cells, and an output interface coupled to the circuitry and to wordlines (WLs) of the memory array. In embodiments, the circuitry, in a deck erase operation may: apply a first set of bias voltages via the output interface to active WLs of at least a first deck of the two or more decks of memory cells to be erased; and apply a second set of bias voltages via the output interface to active WLs of at least a second deck of the two or more decks of memory cells not to be erased, wherein the first set of bias voltages is lower than the second set of bias voltages.
    Type: Grant
    Filed: December 8, 2017
    Date of Patent: June 18, 2019
    Assignee: Intel Corporation
    Inventors: Richard Fastow, Xin Sun, Uday Chandrasekhar, Krishna K. Parat, Camila Jaramillo, Purval S. Sule, Aliasgar S. Madraswala
  • Publication number: 20190043563
    Abstract: An apparatus and/or system is described including a memory device or a controller to perform programming and verification operations including application of a shared voltage level to verify two program voltage levels of a multi-level cell device. For example, in embodiments, the control circuitry performs a program operation to program a memory cell and performs a verification operation by applying a single or shared verify voltage level to verify that the memory cell is programmed to a corresponding program voltage level. In embodiments, the program voltage level is one of two consecutive program voltage levels of a plurality of program voltage levels to be verified by application of the shared verify voltage. Other embodiments are disclosed and claimed.
    Type: Application
    Filed: September 28, 2018
    Publication date: February 7, 2019
    Inventors: Ali Khakifirooz, Pranav Kalavade, Uday Chandrasekhar, Trupti Bemalkhedkar, Chang Wan Ha
  • Publication number: 20190043591
    Abstract: A controller for a NAND memory array is presented. In embodiments, the controller may include circuitry to provide bias voltages to a NAND memory array that includes two or more decks of memory cells, and an output interface coupled to the circuitry and to wordlines (WLs) of the memory array. In embodiments, the circuitry, in a deck erase operation may: apply a first set of bias voltages via the output interface to active WLs of at least a first deck of the two or more decks of memory cells to be erased; and apply a second set of bias voltages via the output interface to active WLs of at least a second deck of the two or more decks of memory cells not to be erased, wherein the first set of bias voltages is lower than the second set of bias voltages.
    Type: Application
    Filed: December 8, 2017
    Publication date: February 7, 2019
    Inventors: RICHARD FASTOW, XIN SUN, UDAY CHANDRASEKHAR, KRISHNA K. PARAT, CAMILA JARAMILLO, PURVAL S. SULE, ALIASGAR S. MADRASWALA
  • Publication number: 20190006016
    Abstract: A programming of a memory device configurable to reach a plurality of voltage levels is initiated. For each voltage level to be reached, a checkpoint is set up within a sequence of program pulses applied for the programming of the memory device, to determine whether a plurality of memory cells of the memory device have reached the voltage level. The programming of the memory device is aborted, in response to determining at the checkpoint that the plurality of memory cells have not reached the voltage level.
    Type: Application
    Filed: June 29, 2017
    Publication date: January 3, 2019
    Inventors: Ali KHAKIFIROOZ, Pranav KALAVADE, Shantanu R. RAJWADE, Aliasgar S. MADRASWALA, Uday CHANDRASEKHAR, Purval S. SULE, Sagar UPADHYAY
  • Patent number: 9793003
    Abstract: A memory device having features of the present invention comprises a reprogrammable memory portion including therein a first plurality of magnetic tunnel junctions (MTJs) whose resistance is switchable; and a one-time-programmable (OTP) memory portion including therein a second plurality of MTJs whose resistance is switchable and a third plurality of MTJs whose resistance is fixed. Each MTJ of the first, second, and third plurality of MTJs includes a magnetic free layer having a magnetization direction substantially perpendicular to a layer plane thereof and a magnetic reference layer having a fixed magnetization direction substantially perpendicular to a layer plane thereof. The second plurality of MTJs represents one of two logical states and the third plurality of MTJs represents the other one of the two logical states.
    Type: Grant
    Filed: September 14, 2016
    Date of Patent: October 17, 2017
    Assignee: Avalanche Technology, Inc.
    Inventors: Ebrahim Abedifard, Uday Chandrasekhar, Rajiv Yadav Ranjan, Yiming Huai
  • Publication number: 20170076818
    Abstract: A memory device having features of the present invention comprises a reprogrammable memory portion including therein a first plurality of magnetic tunnel junctions (MTJs) whose resistance is switchable; and a one-time-programmable (OTP) memory portion including therein a second plurality of MTJs whose resistance is switchable and a third plurality of MTJs whose resistance is fixed. Each MTJ of the first, second, and third plurality of MTJs includes a magnetic free layer having a magnetization direction substantially perpendicular to a layer plane thereof and a magnetic reference layer having a fixed magnetization direction substantially perpendicular to a layer plane thereof. The second plurality of MTJs represents one of two logical states and the third plurality of MTJs represents the other one of the two logical states.
    Type: Application
    Filed: September 14, 2016
    Publication date: March 16, 2017
    Inventors: Ebrahim Abedifard, Uday Chandrasekhar, Rajiv Yadav Ranjan, Yiming Huai
  • Patent number: 9576674
    Abstract: This disclosure concerns memory cell sensing. One or more methods include determining a data state of a first memory cell coupled to a first data line, determining a data state of a third memory cell coupled to a third data line, transferring determined data of at least one of the first and the third memory cells to a data line control unit corresponding to a second data line to which a second memory cell is coupled, the second data line being adjacent to the first data line and the third data line, and determining a data state of the second memory cell based, at least partially, on the transferred determined data.
    Type: Grant
    Filed: March 19, 2015
    Date of Patent: February 21, 2017
    Assignee: Micron Technology, Inc.
    Inventors: Matthew Goldman, Pranav Kalavade, Uday Chandrasekhar, Mark A. Helm
  • Patent number: 9552888
    Abstract: Methods and devices for data sensing are disclosed. One such method includes performing a number of successive sense operations on a number of memory cells using a number of different sensing voltages, determining a quantity of the number memory cells that change states between consecutive sense operations of the number of successive sense operations, and determining, based at least partially on the determined quantity of the number of memory cells that change states between consecutive sense operations, whether to output hard data corresponding to one of the number of successive sense operations.
    Type: Grant
    Filed: May 28, 2015
    Date of Patent: January 24, 2017
    Assignee: Micron Technology, Inc.
    Inventors: Mark A. Helm, Uday Chandrasekhar
  • Patent number: 9406389
    Abstract: Memory devices and methods are disclosed, such as those facilitating data line shielding by way of capacitive coupling with data lines coupled to a memory string source line. For example, alternating data lines are sensed while adjacent data lines are coupled to a common source line of the data lines being sensed. Data line shielding methods and apparatus disclosed can reduce effects of source line bounce occurring during a sense operation of a memory device.
    Type: Grant
    Filed: November 7, 2014
    Date of Patent: August 2, 2016
    Assignee: Micron Technology, Inc.
    Inventor: Uday Chandrasekhar
  • Patent number: 9251908
    Abstract: This disclosure concerns memory kink checking. One embodiment includes selectively applying one of a plurality of voltages to a first data line according to a programming status of a first memory cell, wherein the first memory cell is coupled to the first data line and to a selected access line. An effect on a second data line is determined, due at least in part to the voltage applied to the first data line and a capacitive coupling between at least the first data line and the second data line, wherein the second data line is coupled to a second memory cell, the second memory cell is adjacent to the first memory cell, and the second memory cell is coupled to the selected access line. A kink correction is applied to the second data line, responsive to the determined effect, during a subsequent programming pulse applied to the second memory cell.
    Type: Grant
    Filed: March 27, 2014
    Date of Patent: February 2, 2016
    Assignee: Micron Technology, Inc.
    Inventors: Uday Chandrasekhar, Mark A. Helm
  • Patent number: 9229801
    Abstract: A data storage device includes a non-volatile memory and a controller. A method includes receiving first data and second data from a host device. A first error-correcting code (ECC) codeword associated with the first data is written to a first word line of the non-volatile memory, and a second ECC codeword associated with the second data is written to a second word line of the non-volatile memory. The first ECC codeword includes a first bit and a second bit, and the second ECC codeword includes a third bit and a fourth bit. The method further includes writing parity information to a parity storage portion of the non-volatile memory that is distinct from the first word line and from the second word line. The parity information includes a parity bit that is based on the first bit, the second bit, the third bit, and the fourth bit.
    Type: Grant
    Filed: September 24, 2013
    Date of Patent: January 5, 2016
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Uday Chandrasekhar, Jianmin Huang, Steven Sprouse, Nian Niles Yang, Xinde Hu
  • Publication number: 20150262695
    Abstract: The present disclosure includes methods and devices for data sensing. One such method includes performing a number of successive sense operations on a number of memory cells using a number of different sensing voltages, determining a quantity of the number memory cells that change states between consecutive sense operations of the number of successive sense operations, and determining, based at least partially on the determined quantity of the number of memory cells that change states between consecutive sense operations, whether to output hard data corresponding to one of the number of successive sense operations.
    Type: Application
    Filed: May 28, 2015
    Publication date: September 17, 2015
    Inventors: Mark A. Helm, Uday Chandrasekhar
  • Patent number: 9110822
    Abstract: A data storage device includes a non-volatile memory that includes a three-dimensional (3D) memory. A method includes receiving first data and second data from a host device. A first error-correcting code (ECC) codeword associated with the first data is written to a first word line of the non-volatile memory, and a second ECC codeword associated with the second data is written to a second word line of the non-volatile memory. The first ECC codeword includes a first bit and a second bit, and the second ECC codeword includes a third bit and a fourth bit. The method further includes writing parity information to a parity storage portion of the non-volatile memory that is distinct from the first word line and from the second word line. The parity information includes a parity bit that is based on the first bit, the second bit, the third bit, and the fourth bit.
    Type: Grant
    Filed: May 28, 2014
    Date of Patent: August 18, 2015
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Uday Chandrasekhar, Jianmin Huang, Steven Sprouse, Nian Niles Yang, Xinde Hu
  • Publication number: 20150194218
    Abstract: This disclosure concerns memory cell sensing. One or more methods include determining a data state of a first memory cell coupled to a first data line, determining a data state of a third memory cell coupled to a third data line, transferring determined data of at least one of the first and the third memory cells to a data line control unit corresponding to a second data line to which a second memory cell is coupled, the second data line being adjacent to the first data line and the third data line, and determining a data state of the second memory cell based, at least partially, on the transferred determined data.
    Type: Application
    Filed: March 19, 2015
    Publication date: July 9, 2015
    Inventors: Matthew Goldman, Pranav Kalavade, Uday Chandrasekhar, Mark A. Helm
  • Patent number: 9070449
    Abstract: In a flash memory, erase blocks containing shorted or broken word lines may be used, at least in part, to store user data. Such blocks may use different parameters to those used by non-defective blocks, may be subject to different wear leveling, and may store data selected to reduce the number of access operations.
    Type: Grant
    Filed: April 26, 2013
    Date of Patent: June 30, 2015
    Assignee: SanDisk Technologies Inc.
    Inventors: Nian Niles Yang, Uday Chandrasekhar, Yichao Huang, Alexandra Bauche, William S. Wu
  • Patent number: 9047972
    Abstract: Methods, devices, and systems for data sensing in a memory system can include performing a number of successive sense operations on a number of memory cells using a number of different sensing voltages, determining a quantity of the number memory cells that change states between consecutive sense operations of the number of successive sense operations, and determining, based at least partially on the determined quantity of the number of memory cells that change states between consecutive sense operations, whether to output hard data corresponding to one of the number of successive sense operations.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: June 2, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Mark A. Helm, Uday Chandrasekhar
  • Patent number: 9009568
    Abstract: Disclosed is a technology to change the parameters by which a read operation is performed in a block with a broken word line. The first method is for reading a broken word line, which may involve changing the voltage on word lines neighboring the broken word line to let the voltage on the broken word line reach the appropriate magnitude through capacitive coupling between word lines. The first method may also involve increasing the time delay before memory cells connected to the broken word line are sensed to allow the voltage on the word line to settle due to increased RC delay. The second method is for reading an unbroken word line in a block with a broken word line, which involves increasing the time delay before memory cells connected to the unbroken word line are sensed while raising the voltages on the word lines neighboring the broken word line.
    Type: Grant
    Filed: August 9, 2013
    Date of Patent: April 14, 2015
    Assignee: Sandisk Technologies Inc.
    Inventors: Ting Luo, Nian Niles Yang, Chris Avila, Uday Chandrasekhar, Jianmin Huang
  • Patent number: 9001577
    Abstract: This disclosure concerns memory cell sensing. One or more methods include determining a data state of a first memory cell coupled to a first data line, determining a data state of a third memory cell coupled to a third data line, transferring determined data of at least one of the first and the third memory cells to a data line control unit corresponding to a second data line to which a second memory cell is coupled, the second data line being adjacent to the first data line and the third data line, and determining a data state of the second memory cell based, at least partially, on the transferred determined data.
    Type: Grant
    Filed: June 1, 2012
    Date of Patent: April 7, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Matthew Goldman, Pranav Kalavade, Uday Chandrasekhar, Mark A. Helm
  • Publication number: 20150089325
    Abstract: A data storage device includes a non-volatile memory that includes a three-dimensional (3D) memory. A method includes receiving first data and second data from a host device. A first error-correcting code (ECC) codeword associated with the first data is written to a first word line of the non-volatile memory, and a second ECC codeword associated with the second data is written to a second word line of the non-volatile memory. The first ECC codeword includes a first bit and a second bit, and the second ECC codeword includes a third bit and a fourth bit. The method further includes writing parity information to a parity storage portion of the non-volatile memory that is distinct from the first word line and from the second word line. The parity information includes a parity bit that is based on the first bit, the second bit, the third bit, and the fourth bit.
    Type: Application
    Filed: May 28, 2014
    Publication date: March 26, 2015
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: UDAY CHANDRASEKHAR, JIANMIN HUANG, STEVEN SPROUSE, NIAN NILES YANG, XINDE HU