Patents by Inventor Vishal Sarin

Vishal Sarin 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: 9349474
    Abstract: Apparatuses, current control circuits, and methods for limiting string current in a memory are described. An example apparatus includes a memory cell string including a memory cell. The example apparatus further includes a sense circuit configured to sense a current through the memory cell string, and a select gate configured to couple the memory cell string to a source based on a select gate voltage. The example apparatus further includes a current control circuit coupled to the select gate. The current control circuit is configured to limit current through the memory cell string during a memory access operation based on a reference current.
    Type: Grant
    Filed: June 21, 2013
    Date of Patent: May 24, 2016
    Assignee: Micron Technology, Inc.
    Inventor: Vishal Sarin
  • Patent number: 9240240
    Abstract: Methods and apparatus utilizing indications of memory cell density facilitate management of memory density of a memory device. By permitting each of a plurality of portions of a memory array of the memory device to be assigned a corresponding memory cell density determined through an evaluation of those portions of the memory array, better performing portions of the memory array may not be hindered by lesser performing portions of the memory array.
    Type: Grant
    Filed: November 29, 2011
    Date of Patent: January 19, 2016
    Assignee: Micron Technology, Inc.
    Inventors: Frankie F. Roohparvar, Vishal Sarin
  • Patent number: 9236146
    Abstract: Memory devices and methods of operating memory devices are shown. Configurations described include circuits to perform a single check between programming pulses to determine a threshold voltage with respect to desired benchmark voltages. In one example, the benchmark voltages are used to change a programming speed of selected memory cells.
    Type: Grant
    Filed: April 28, 2014
    Date of Patent: January 12, 2016
    Assignee: Micron Technology, Inc.
    Inventors: Vishal Sarin, Aaron Yip, Tomoharu Tanaka
  • Publication number: 20150355849
    Abstract: Methods for sensing, method for programming, memory devices, and memory systems are disclosed. In one such method for sensing, a counting circuit generates a count output and a translated count output. The count output is converted into a time varying voltage that biases a word line coupled to memory cells being sensed. Target data for each memory cell is stored in a data cache associated with that particular memory cell. When it is detected that a memory cell has turned on, the translated count output associated with the count output that is indicative of the voltage level that turned on the memory cell is compared to the target data. The comparison determines the state of the memory cell.
    Type: Application
    Filed: August 17, 2015
    Publication date: December 10, 2015
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Jonathan Pabustan, Vishal Sarin, Dzung H. Nguyen
  • Patent number: 9196370
    Abstract: The present disclosure includes methods, devices, modules, and systems for reducing noise in semiconductor devices. One method embodiment includes applying a reset voltage to a control gate of a semiconductor device for a period of time. The method further includes sensing the state of the semiconductor device after applying the reset voltage.
    Type: Grant
    Filed: July 16, 2013
    Date of Patent: November 24, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Vishal Sarin, Frankie F. Roohparvar, Jung Sheng Hoei
  • Patent number: 9197251
    Abstract: Methods and apparatus are disclosed related to a memory device, such as a flash memory device that includes an array of memory cells. One such method includes detecting values of charges stored in selected memory cells in the memory cell array. The method also includes processing the detected values in accordance with a Viterbi algorithm so as to determine data stored in the selected memory cells. In one embodiment, the flash memory cell array includes word lines and bit lines. Detecting the values of charges includes detecting values of charges stored in a selected row of memory cells by selecting one of the word lines. The Viterbi algorithm provides correct data where inter-signal interference between the cells affects the accuracy of read data.
    Type: Grant
    Filed: April 4, 2014
    Date of Patent: November 24, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Frankie Roohparvar, Vishal Sarin, William Radke
  • Publication number: 20150325309
    Abstract: Threshold voltages in a charge storage memory are controlled by threshold voltage placement, such as to provide more reliable operation and to reduce the influence of factors such as neighboring charge storage elements and parasitic coupling. Pre-compensation or post-compensation of threshold voltage for neighboring programmed aggressor memory cells reduces the threshold voltage uncertainty in a flash memory system. Using a buffer having a data structure such as a lookup table provides for programmable threshold voltage distributions that enables the distribution of data states in a multi-level cell flash memory to be tailored, such as to provide more reliable operation. Additional apparatus, systems, and methods are provided.
    Type: Application
    Filed: July 20, 2015
    Publication date: November 12, 2015
    Inventors: Violante Moschiano, Tommaso Vali, Giovanni Naso, Vishal Sarin, William Henry Radke, Theodore T. Pekny
  • Patent number: 9177651
    Abstract: Methods of programming a memory and memories are disclosed. In at least one embodiment, a memory is programmed by determining a pretarget threshold voltage for a selected cell, wherein the pretarget threshold voltage is determined using pretarget threshold voltage values for at least one neighbor cell of the selected cell.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: November 3, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Vishal Sarin, William H. Radke, Frankie F. Roohparvar
  • Patent number: 9165681
    Abstract: In an embodiment, a defective memory block is replaced with a non-defective memory block, and a voltage-delay correction is applied to the non-defective memory block that replaces the defective memory block based on the actual location of the non-defective memory block.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: October 20, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Vishal Sarin, Dzung H. Nguyen, William H. Radke
  • Patent number: 9158612
    Abstract: In one or more of the disclosed embodiments, memory cells in a memory device are refreshed upon an indication of a fatigue condition. In one such embodiment, controller monitors behavior parameters of the cells and determines if any of the parameters are outside of a normal range set for each one, thus indicating a fatigue condition. If any cell indicates a fatigue condition, the data from the block of cells indicating the fatigue is moved to another block. In one embodiment, an error detection and correction process is performed on the data prior to being written into another memory block.
    Type: Grant
    Filed: October 4, 2013
    Date of Patent: October 13, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Frankie F. Roohparvar, Vishal Sarin, Jung S. Hoei
  • Patent number: 9147476
    Abstract: Methods of programming a memory and memories are disclosed. In at least one embodiment, a memory is programmed by determining a pretarget threshold voltage for a selected cell, wherein the pretarget threshold voltage is determined using pretarget threshold voltage values for at least one neighbor cell of the selected cell.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: September 29, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Vishal Sarin, William H. Radke, Frankie F. Roohparvar
  • Publication number: 20150262657
    Abstract: Programming a memory in two parts to reduce cell disturb is disclosed. In at least one embodiment, data is programmed in two or more sequences of programming pulses with data requiring higher programming voltages programmed first. During each programming sequence, the data which is not being currently selected for programming is inhibited. Overlapping levels and/or voltage ranges can be used.
    Type: Application
    Filed: May 29, 2015
    Publication date: September 17, 2015
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Vishal Sarin, Allahyar Vahidimowlavi
  • Patent number: 9123423
    Abstract: Methods for sensing, method for programming, memory devices, and memory systems are disclosed. In one such method for sensing, a counting circuit generates a count output and a translated count output. The count output is converted into a time varying voltage that biases a word line coupled to memory cells being sensed. Target data for each memory cell is stored in a data cache associated with that particular memory cell. When it is detected that a memory cell has turned on, the translated count output associated with the count output that is indicative of the voltage level that turned on the memory cell is compared to the target data. The comparison determines the state of the memory cell.
    Type: Grant
    Filed: December 12, 2013
    Date of Patent: September 1, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Jonathan Pabustan, Vishal Sarin, Dzung H. Nguyen
  • Publication number: 20150243351
    Abstract: Threshold voltages in a charge storage memory are controlled by threshold voltage placement, such as to provide more reliable operation and to reduce the influence of factors such as neighboring charge storage elements and parasitic coupling. Pre-compensation or post-compensation of threshold voltage for neighboring programmed “aggressor” memory cells reduces the threshold voltage uncertainty in a flash memory system. Using a buffer having a data structure such as a lookup table provides for programmable threshold voltage distributions that enables the distribution of data states in a multi-level cell flash memory to be tailored, such as to provide more reliable operation.
    Type: Application
    Filed: May 8, 2015
    Publication date: August 27, 2015
    Inventors: Violante Moschiano, Tommaso Vali, Giovanni Naso, Vishal Sarin, William Henry Radke, Theodore T. Pekny
  • Patent number: 9093162
    Abstract: The present disclosure includes methods, devices, modules, and systems for operating memory cells. One method embodiment includes applying a ramping voltage to a control gate of a memory cell and to an analog-to-digital converter (ADC). The aforementioned embodiment of a method also includes detecting an output of the ADC at least partially in response to when the ramping voltage causes the memory cell to trip sense circuitry.
    Type: Grant
    Filed: October 4, 2013
    Date of Patent: July 28, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Vishal Sarin, Jung Sheng Hoei, Frankie Roohparvar, Giulio-Giuseppe Marotta
  • Patent number: 9087600
    Abstract: Programming a memory in two parts to reduce cell disturb is disclosed. In at least one embodiment, data is programmed in two or more sequences of programming pulses with data requiring higher programming voltages programmed first. During each programming sequence, the data which is not being currently selected for programming is inhibited. Overlapping levels and/or voltage ranges can be used.
    Type: Grant
    Filed: December 22, 2011
    Date of Patent: July 21, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Vishal Sarin, Allahyar Vahidimowlavi
  • Patent number: 9087594
    Abstract: Threshold voltages in a charge storage memory are controlled by threshold voltage placement, such as to provide more reliable operation and to reduce the influence of factors such as neighboring charge storage elements and parasitic coupling. Pre-compensation or post-compensation of threshold voltage for neighboring programmed aggressor memory cells reduces the threshold voltage uncertainty in a flash memory system. Using a buffer having a data structure such as a lookup table provides for programmable threshold voltage distributions that enables the distribution of data states in a multi-level cell flash memory to be tailored, such as to provide more reliable operation. Additional apparatus, systems, and methods are provided.
    Type: Grant
    Filed: July 31, 2012
    Date of Patent: July 21, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Violante Moschiano, Tommaso Vali, Giovanni Naso, Vishal Sarin, William Henry Radke, Theodore T. Pekny
  • Patent number: 9030870
    Abstract: Threshold voltages in a charge storage memory are controlled by threshold voltage placement, such as to provide more reliable operation and to reduce the influence of factors such as neighboring charge storage elements and parasitic coupling. Pre-compensation or post-compensation of threshold voltage for neighboring programmed “aggressor” memory cells reduces the threshold voltage uncertainty in a flash memory system. Using a buffer having a data structure such as a lookup table provides for programmable threshold voltage distributions that enables the distribution of data states in a multi-level cell flash memory to be tailored, such as to provide more reliable operation.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: May 12, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Violante Moschiano, Tommaso Vali, Giovanni Naso, Vishal Sarin, William Henry Radke, Theodore T. Pekny
  • Patent number: 9025388
    Abstract: This disclosure concerns memory kink compensation. One method embodiment includes applying a number of sequentially incrementing programming pulses to a memory cell, with the sequential programming pulses incrementing by a first programming pulse step voltage magnitude. A seeding voltage is applied after applying the number of sequentially incrementing programming pulses. A next programming pulse is applied after applying the seeding voltage, with the next programming pulse being adjusted relative to a preceding one of the sequentially incrementing programming pulses by a second programming pulse step voltage magnitude. The second programming pulse step voltage magnitude can be less than the first programming pulse step voltage magnitude.
    Type: Grant
    Filed: October 3, 2013
    Date of Patent: May 5, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Violante Moschiano, Frankie Roohparvar, Giovanni Santin, Vishal Sarin, Allahyar Vahidimowlavi, Tommaso Vali
  • Patent number: 8995182
    Abstract: Memory devices adapted to receive and transmit analog data signals representative of bit patterns of two or more bits facilitate increases in data transfer rates relative to devices communicating data signals indicative of individual bits. Programming of such memory devices includes initially programming a cell with a coarse programming pulse to move its threshold voltage in a large step close to the programmed state. The neighboring cells are then programmed using coarse programming. The algorithm then returns to the initially programmed cells that are then programmed with one or more fine pulses that slowly move the threshold voltage in smaller steps to the final programmed state threshold voltage.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: March 31, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Frankie F. Roohparvar, Vishal Sarin, Jung-Sheng Hoei