Patents by Inventor Mohan V. Dunga

Mohan V. Dunga 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: 11031085
    Abstract: A non-volatile memory system comprises a memory structure and a control circuit connected to the memory structure. The memory structure includes one or more planes of non-volatile memory cells. Each plane is divided into a plurality of partial planes. The control circuit is configured to write to and read from the memory cells by writing a partial page into a particular partial plane and reading the partial page from the particular partial plane using a set of parameters optimized for the particular partial plane.
    Type: Grant
    Filed: June 9, 2020
    Date of Patent: June 8, 2021
    Assignee: SanDisk Technologies LLC
    Inventors: Mohan V Dunga, Pitamber Shukla
  • Publication number: 20200303010
    Abstract: A non-volatile memory system comprises a memory structure and a control circuit connected to the memory structure. The memory structure includes one or more planes of non-volatile memory cells. Each plane is divided into a plurality of partial planes. The control circuit is configured to write to and read from the memory cells by writing a partial page into a particular partial plane and reading the partial page from the particular partial plane using a set of parameters optimized for the particular partial plane.
    Type: Application
    Filed: June 9, 2020
    Publication date: September 24, 2020
    Applicant: SanDisk Technologies LLC
    Inventors: Mohan V. Dunga, Pitamber Shukla
  • Patent number: 10741251
    Abstract: A non-volatile memory system comprises a memory structure and a control circuit connected to the memory structure. The memory structure includes one or more planes of non-volatile memory cells. Each plane is divided into a plurality of partial planes. The control circuit is configured to write to and read from the memory cells by writing a partial page into a particular partial plane and reading the partial page from the particular partial plane using a set of parameters optimized for the particular partial plane.
    Type: Grant
    Filed: April 17, 2018
    Date of Patent: August 11, 2020
    Assignee: SanDisk Technologies LLC
    Inventors: Mohan V Dunga, Pitamber Shukla
  • Publication number: 20190180822
    Abstract: A non-volatile memory system comprises a memory structure and a control circuit connected to the memory structure. The memory structure includes one or more planes of non-volatile memory cells. Each plane is divided into a plurality of partial planes. The control circuit is configured to write to and read from the memory cells by writing a partial page into a particular partial plane and reading the partial page from the particular partial plane using a set of parameters optimized for the particular partial plane.
    Type: Application
    Filed: April 17, 2018
    Publication date: June 13, 2019
    Applicant: SanDisk Technologies LLC
    Inventors: Mohan V Dunga, Pitamber Shukla
  • Patent number: 9349452
    Abstract: A non-volatile storage system includes a plurality of groups of connected non-volatile storage elements. Each group comprises multiple connected data non-volatile storage elements and multiple select gates on a common side of the data non-volatile storage elements. The multiple select gates comprise a first select gate and a second select gate. The first select gate has a first threshold voltage for a first subset of the groups and a second threshold voltage for a second subset of the groups due to active area implantation for the second subset of groups that causes the second threshold voltage to be lower than the first threshold voltage. The second select gate of each group has a programmable threshold voltage. Each of the plurality of bit lines are connected to multiple groups of connected non-volatile storage elements.
    Type: Grant
    Filed: March 7, 2013
    Date of Patent: May 24, 2016
    Assignee: SanDisk Technologies Inc.
    Inventors: Mohan V. Dunga, Masaaki Higashitani
  • Patent number: 9165656
    Abstract: A non-volatile storage system is disclosed that includes pairs (or another number) of NAND strings (or other groupings of memory cells) in the same block being connected to and sharing a common bit line. By sharing bit lines, less bit lines are needed in the storage system. Using less bit lines reduces the space needed to implement the storage system. Each NAND string will have two drain side select gates. The non-volatile storage system will have two drain side selection lines each connected to one of the two drain side select gates so that the NAND strings sharing a bit line can be individually selected. To allow proper selection of a NAND string using the select gates, the select gates will be subjected to non-volatile programming in order to set the threshold voltage of the select gates to an appropriate level.
    Type: Grant
    Filed: March 11, 2013
    Date of Patent: October 20, 2015
    Assignee: SanDisk Technologies Inc.
    Inventors: Mohan V. Dunga, Masaaki Higashitani
  • Patent number: 9082502
    Abstract: In a block of non-volatile memory, bit line current increases with bit line voltage. For current sensing memory systems, average bit line current during a sensing operation need only exceed a certain threshold amount in order to produce a correct result. For the first word lines being programmed in a block, memory cells connected thereto see relatively low bit line resistances during verify operations. In the disclosed technology, verify operations are performed for these first programmed word lines with lower verify bit line voltages in order to reduce excess bit line current and save power. During read operations, this scheme can make threshold voltages of memory cells connected to the lower word lines appear lower. In order to compensate for this effect, various schemes are disclosed.
    Type: Grant
    Filed: October 10, 2013
    Date of Patent: July 14, 2015
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Mohan V. Dunga, Masaaki Higashitani
  • 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: 9047971
    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: May 29, 2014
    Date of Patent: June 2, 2015
    Assignee: SanDisk Technologies, Inc.
    Inventors: Nima Mokhlesi, Mohan V. Dunga, Man Mui
  • Publication number: 20150103595
    Abstract: In a block of non-volatile memory, bit line current increases with bit line voltage. For current sensing memory systems, average bit line current during a sensing operation need only exceed a certain threshold amount in order to produce a correct result. For the first word lines being programmed in a block, memory cells connected thereto see relatively low bit line resistances during verify operations. In the disclosed technology, verify operations are performed for these first programmed word lines with lower verify bit line voltages in order to reduce excess bit line current and save power. During read operations, this scheme can make threshold voltages of memory cells connected to the lower word lines appear lower. In order to compensate for this effect, various schemes are disclosed.
    Type: Application
    Filed: October 10, 2013
    Publication date: April 16, 2015
    Applicant: Sandisk Technologies, Inc.
    Inventors: Mohan V. Dunga, Masaaki Higashitani
  • Publication number: 20140269082
    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: Application
    Filed: May 29, 2014
    Publication date: September 18, 2014
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Nima Mokhlesi, Mohan V. Dunga, Man Mui
  • Patent number: 8837216
    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.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: September 16, 2014
    Assignee: Sandisk Technologies Inc.
    Inventors: Nima Mokhlesi, Mohan V. Dunga, Masaaki Higashitani
  • Publication number: 20140254269
    Abstract: A non-volatile storage system is disclosed that includes pairs (or another number) of NAND strings (or other groupings of memory cells) in the same block being connected to and sharing a common bit line. By sharing bit lines, less bit lines are needed in the storage system. Using less bit lines reduces the space needed to implement the storage system. Each NAND string will have two drain side select gates. The non-volatile storage system will have two drain side selection lines each connected to one of the two drain side select gates so that the NAND strings sharing a bit line can be individually selected. To allow proper selection of a NAND string using the select gates, the select gates will be subjected to non-volatile programming in order to set the threshold voltage of the select gates to an appropriate level.
    Type: Application
    Filed: March 11, 2013
    Publication date: September 11, 2014
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Mohan V. Dunga, Masaaki Higashitani
  • Publication number: 20140254268
    Abstract: A non-volatile storage system includes a plurality of groups of connected non-volatile storage elements. Each group comprises multiple connected data non-volatile storage elements and multiple select gates on a common side of the data non-volatile storage elements. The multiple select gates comprise a first select gate and a second select gate. The first select gate has a first threshold voltage for a first subset of the groups and a second threshold voltage for a second subset of the groups due to active area implantation for the second subset of groups that causes the second threshold voltage to be lower than the first threshold voltage. The second select gate of each group has a programmable threshold voltage. Each of the plurality of bit lines are connected to multiple groups of connected non-volatile storage elements.
    Type: Application
    Filed: March 7, 2013
    Publication date: September 11, 2014
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Mohan V. Dunga, Masaaki Higashitani
  • Publication number: 20120147676
    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.
    Type: Application
    Filed: May 13, 2011
    Publication date: June 14, 2012
    Inventors: Nima Mokhlesi, Mohan V. Dunga, Masaaki Higashitani
  • Patent number: 7755946
    Abstract: Temperature effects in a non-volatile storage device are addressed by providing a data state-dependent, and optionally temperature dependent, sense current during verify and read operations. A different sense current is provided for each data state, so that a common temperature coefficient is realized for storage elements with different data states. The temperature coefficient for higher states can be reduced to that of lower states. During sensing, a sense time can be adjusted to achieve a desired sense current when a selected storage element is in a conductive state. A fixed voltage trip point may be maintained. During the sense time, a pre-charged capacitor discharges into a selected storage element such as via a bit line and NAND string, when the selected storage element is in a conductive state. The discharge level is translated to a current which is compared to a state-dependent, and optionally temperature dependent, reference current.
    Type: Grant
    Filed: September 19, 2008
    Date of Patent: July 13, 2010
    Assignee: Sandisk Corporation
    Inventors: Mohan V. Dunga, Masaaki Higashitani
  • Publication number: 20100074014
    Abstract: Temperature effects in a non-volatile storage device are addressed by providing a data state-dependent, and optionally temperature dependent, sense current during verify and read operations. A different sense current is provided for each data state, so that a common temperature coefficient is realized for storage elements with different data states. The temperature coefficient for higher states can be reduced to that of lower states. During sensing, a sense time can be adjusted to achieve a desired sense current when a selected storage element is in a conductive state. A fixed voltage trip point may be maintained. During the sense time, a pre-charged capacitor discharges into a selected storage element such as via a bit line and NAND string, when the selected storage element is in a conductive state. The discharge level is translated to a current which is compared to a state-dependent, and optionally temperature dependent, reference current.
    Type: Application
    Filed: September 19, 2008
    Publication date: March 25, 2010
    Inventors: Mohan V. Dunga, Masaaki Higashitani