Patents by Inventor Nima Mokhlesi

Nima Mokhlesi 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: 10157681
    Abstract: A series of programming pulses, where the individual pulses are identified by a pulse number, is used to program a page of memory cells in parallel. After receiving a pulse, the memory cells under verification are verified to determine if they have been programmed to their respective target states. The memory cells that have been verified are inhibited from further programming while those memory cells not verified will be further programmed by subsequent programming pulses. The pulsing, verification and inhibition continue until all memory cells of the page have been program-verified. Each verify level used in the verification is a function of both the target state and the pulse number. This allows adjustment of the verify level to compensate for changes in sensing, including those due to variation in source line loading during the course of programming.
    Type: Grant
    Filed: September 14, 2015
    Date of Patent: December 18, 2018
    Assignee: SanDisk Technologies LLC
    Inventor: Nima Mokhlesi
  • Patent number: 9947682
    Abstract: A three dimensional stacked non-volatile memory device comprises alternating dielectric layers and conductive layers in a stack, a plurality of bit lines below the stack, and a plurality of source lines above the stack. There is a separate source line for each bit line. Each source lines is connected to a different subset of NAND strings. Each bit line is connected to a different subset of NAND strings. Multiple data states are verified concurrently. Reading is performed sequentially for the data states. The data states are programmed concurrently with memory cells being programmed to lower data states having their programming slowed by applying appropriate source line voltages and bit line voltages.
    Type: Grant
    Filed: October 27, 2015
    Date of Patent: April 17, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Nima Mokhlesi, Alexander Chu
  • Patent number: 9911488
    Abstract: A non-volatile storage system dedicates a subset of blocks to be used for shorting source lines to bit lines at periodic positions along the bit lines during certain memory operations.
    Type: Grant
    Filed: October 20, 2016
    Date of Patent: March 6, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventor: Nima Mokhlesi
  • Patent number: 9715924
    Abstract: A non-volatile memory system includes a plurality of non-volatile memory cells, one or more control circuits that perform programming of the memory cells, a power supply line that provides a supply used to program the memory cells, and a current measurement circuit. The current measurement circuit senses an indication of current on the power supply line. The one or more control circuits determine whether the programming of the memory cells is successful based on the indication of current.
    Type: Grant
    Filed: October 20, 2016
    Date of Patent: July 25, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Nima Mokhlesi, Ali Al-Shamma
  • Publication number: 20170117036
    Abstract: A non-volatile storage system includes a plurality of non-volatile memory cells configured to form a monolithic three dimensional memory structure, a plurality of bit lines connected to the memory cells, a plurality of source lines connected to the memory cells, a plurality of bit line drivers connected to the bit lines and a plurality of source line drivers connected to the source lines and the bit lines. The source line drivers apply voltages to the source lines based on bit line voltages.
    Type: Application
    Filed: October 20, 2016
    Publication date: April 27, 2017
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Ali Al-Shamma, Nima Mokhlesi
  • Publication number: 20170117037
    Abstract: A non-volatile storage system dedicates a subset of blocks to be used for shorting source lines to bit lines at periodic positions along the bit lines during certain memory operations.
    Type: Application
    Filed: October 20, 2016
    Publication date: April 27, 2017
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventor: Nima Mokhlesi
  • Publication number: 20170117035
    Abstract: A non-volatile memory system includes a plurality of non-volatile memory cells, one or more control circuits that perform programming of the memory cells, a power supply line that provides a supply used to program the memory cells, and a current measurement circuit. The current measurement circuit senses an indication of current on the power supply line. The one or more control circuits determine whether the programming of the memory cells is successful based on the indication of current.
    Type: Application
    Filed: October 20, 2016
    Publication date: April 27, 2017
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Nima Mokhlesi, Ali Al-Shamma
  • Publication number: 20170076802
    Abstract: A series of programming pulses, where the individual pulses are identified by a pulse number, is used to program a page of memory cells in parallel. After receiving a pulse, the memory cells under verification are verified to determine if they have been programmed to their respective target states. The memory cells that have been verified are inhibited from further programming while those memory cells not verified will be further programmed by subsequent programming pulses. The pulsing, verification and inhibition continue until all memory cells of the page have been program-verified. Each verify level used in the verification is a function of both the target state and the pulse number. This allows adjustment of the verify level to compensate for changes in sensing, including those due to variation in source line loading during the course of programming.
    Type: Application
    Filed: September 14, 2015
    Publication date: March 16, 2017
    Inventor: Nima Mokhlesi
  • Patent number: 9570185
    Abstract: A system and methods to find the threshold voltage distribution across a set of nonvolatile memory cells, such that embodiments may incorporate this distribution information into calculations that may change the read compare voltages used to read the memory cells, while ensuring adequate separation in read voltage between different data states at which the memory cells may be read.
    Type: Grant
    Filed: May 29, 2015
    Date of Patent: February 14, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventor: Nima Mokhlesi
  • Patent number: 9570184
    Abstract: A system and methods to find the threshold voltage distribution across a set of nonvolatile memory cells, such that embodiments may incorporate this distribution information into calculations that may change the read compare voltages used to read the memory cells, while ensuring adequate separation in read voltage between different data states at which the memory cells may be read.
    Type: Grant
    Filed: May 29, 2015
    Date of Patent: February 14, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventor: Nima Mokhlesi
  • Publication number: 20160141301
    Abstract: A three dimensional stacked non-volatile memory device comprises alternating dielectric layers and conductive layers in a stack, a plurality of bit lines below the stack, and a plurality of source lines above the stack. There is a separate source line for each bit line. Each source lines is connected to a different subset of NAND strings. Each bit line is connected to a different subset of NAND strings. Multiple data states are verified concurrently. Reading is performed sequentially for the data states. The data states are programmed concurrently with memory cells being programmed to lower data states having their programming slowed by applying appropriate source line voltages and bit line voltages.
    Type: Application
    Filed: October 27, 2015
    Publication date: May 19, 2016
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Nima Mokhlesi, Alexander Chu
  • Publication number: 20150380096
    Abstract: A system and methods to find the threshold voltage distribution across a set of nonvolatile memory cells, such that embodiments may incorporate this distribution information into calculations that may change the read compare voltages used to read the memory cells, while ensuring adequate separation in read voltage between different data states at which the memory cells may be read.
    Type: Application
    Filed: May 29, 2015
    Publication date: December 31, 2015
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventor: Nima Mokhlesi
  • Publication number: 20150371712
    Abstract: A system and methods to find the threshold voltage distribution across a set of nonvolatile memory cells, such that embodiments may incorporate this distribution information into calculations that may change the read compare voltages used to read the memory cells, while ensuring adequate separation in read voltage between different data states at which the memory cells may be read.
    Type: Application
    Filed: May 29, 2015
    Publication date: December 24, 2015
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventor: Nima Mokhlesi
  • Patent number: 9076544
    Abstract: A non-volatile storage system is disclosed that includes pairs of NAND strings (or other groupings of memory cells) in the same block being connected to and sharing a common bit line. To operate the system, two selection lines are used so that the NAND strings (or other groupings of memory cells) sharing a bit line can be selected at the block level. Both selection lines are connected to a selection gate for each of the NAND strings (or other groupings of memory cells) sharing the bit line. One set of embodiments avoid unwanted boosting during read operations by keeping the channels of the memory cells connected to word lines on the drain side of the selected word line biased at a fixed potential.
    Type: Grant
    Filed: November 12, 2012
    Date of Patent: July 7, 2015
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Nima Mokhlesi, Mohan V. Dunga, Man Mui
  • Patent number: 9076545
    Abstract: A system and methods to find the threshold voltage distribution across a set of nonvolatile memory cells, such that embodiments may incorporate this distribution information into calculations that may change the read compare voltages used to read the memory cells, while ensuring adequate separation in read voltage between different data states at which the memory cells may be read.
    Type: Grant
    Filed: January 17, 2013
    Date of Patent: July 7, 2015
    Assignee: SANDISK TECNOLOGIES INC.
    Inventor: Nima Mokhlesi
  • Patent number: RE46279
    Abstract: Shifts in the apparent charge stored on a floating gate (or other charge storing element) of a non-volatile memory cell can occur because of the coupling of an electric field based on the charge stored in adjacent floating gates (or other adjacent charge storing elements). The problem occurs most pronouncedly between sets of adjacent memory cells that have been programmed at different times. To account for this coupling, the read process for a particular memory cell will provide compensation to an adjacent memory cell in order to reduce the coupling effect that the adjacent memory cell has on the particular memory cell.
    Type: Grant
    Filed: May 29, 2014
    Date of Patent: January 17, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventor: Nima Mokhlesi
  • Patent number: RE46498
    Abstract: Body bias can be applied to optimize performance in a non-volatile storage system. Body bias can be set in an adaptive manner to reduce an error count of an error correcting and/or detecting code when reading data from non-volatile storage elements. Also, a body bias level can be increased or decreased as a number of programming cycles increases. Also, body bias levels can be set and applied separately for a chip, plane, block and/or page. A body bias can be applied to a first set of NAND strings for which operations are being performed by controlling a first voltage provided to a source side of the first set of NAND strings and a second voltage provided to a p-well. A source side of a second set of NAND strings for which operations are not being performed is floated or receives a fixed voltage.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: August 1, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Deepak Chandra Sekar, Nima Mokhlesi
  • Patent number: RE46573
    Abstract: Methods and devices for simultaneously verifying or reading multiple states in non-volatile storage are disclosed. Methods and devices for efficiently reducing or eliminating cross-coupling effects in non-volatile storage are disclosed. Methods and devices for efficiently performing reads at a number of voltages to search for the threshold voltage of a memory cell are disclosed. Memory cells on different NAND strings that are read at the same time may be tested for different threshold voltage levels. Memory cells may be tested for different threshold voltages by applying different gate-to-source voltages to memory cells being tested for different threshold voltages. Memory cells may be tested for different threshold voltages by applying different drain to source voltages to the memory cells. Different amounts of compensation for cross-coupling affects may be applied to memory cells on different NAND strings that are read or programmed at the same time.
    Type: Grant
    Filed: May 22, 2014
    Date of Patent: October 17, 2017
    Assignee: SanDisk IL Ltd.
    Inventors: Eran Sharon, Yan Li, Nima Mokhlesi
  • Patent number: RE46995
    Abstract: A non-volatile storage system stores data by programming the data as binary data into blocks that have not yet been programmed with multi-state data and have not yet been programmed with binary data X times. The system transfers data from multiple blocks (source blocks) of binary data to one block (target block) of multi-state data using a multi-state programming process, where the target block has been previously programmed with binary data X times (or less than X times).
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: August 14, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventor: Nima Mokhlesi
  • Patent number: RE47226
    Abstract: A process is performed periodically or in response to an error in order to dynamically and adaptively optimize read compare levels based on memory cell threshold voltage distribution. One embodiment of the process includes determining threshold voltage distribution data for a population of non-volatile storage elements, smoothing the threshold voltage distribution data using a weighting function to create an interim set of data, determining a derivative of the interim set of data, and identifying and storing negative to positive zero crossings of the derivative as read compare points.
    Type: Grant
    Filed: March 31, 2014
    Date of Patent: February 5, 2019
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Nima Mokhlesi, Henry Chin