Patents by Inventor Seungpil Lee

Seungpil Lee 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).

  • Publication number: 20210193230
    Abstract: A sense amplifier for a memory circuit is presented that can sense a selected memory cell in either a first sensing mode, in which current from the selected memory cell flows from the memory cells into the sense amplifier, or a second sensing mode, in which current is discharged from the sense amplifier through the selected memory cell. In the first sensing mode, current from a selected memory cell is conducted through cascaded PMOS transistors to charge a sensing node, with the resultant voltage level on the sensing node used to determine the result of the sensing operation.
    Type: Application
    Filed: December 23, 2019
    Publication date: June 24, 2021
    Applicant: SanDisk Technologies LLC
    Inventors: Yingchang Chen, Seungpil Lee, Ali Al-Shamma
  • Patent number: 11031308
    Abstract: A first workpiece includes first active pads, a first test pad, and a second test pad on a primary surface of the first workpiece, the first test pad electrically connected to the second test pad. A second workpiece includes second active pads, a third test pad, and a fourth test pad on a primary surface of the second workpiece. The first and second workpieces are bonded along an interface between the primary surface of the first workpiece and the primary surface of the second workpiece to bond the first active pads with the second active pads, bond the first test pad with the third test pad, and bond the second test pad with the fourth test pad. Connectivity detection circuits test electrical connectivity between the third test pad and the fourth test pad.
    Type: Grant
    Filed: May 30, 2019
    Date of Patent: June 8, 2021
    Assignee: SanDisk Technologies LLC
    Inventors: Seungpil Lee, Kwang-Ho Kim
  • Patent number: 11024392
    Abstract: A sense amplifier for a memory circuit is presented that can sense a selected memory cell in either a first sensing mode, in which current from the selected memory cell flows from the memory cells into the sense amplifier, or a second sensing mode, in which current is discharged from the sense amplifier through the selected memory cell. In the first sensing mode, current from a selected memory cell is conducted through cascaded PMOS transistors to charge a sensing node, with the resultant voltage level on the sensing node used to determine the result of the sensing operation.
    Type: Grant
    Filed: December 23, 2019
    Date of Patent: June 1, 2021
    Assignee: SanDisk Technologies LLC
    Inventors: Yingchang Chen, Seungpil Lee, Ali Al-Shamma
  • Publication number: 20200381316
    Abstract: A first workpiece includes first active pads, a first test pad, and a second test pad on a primary surface of the first workpiece, the first test pad electrically connected to the second test pad. A second workpiece includes second active pads, a third test pad, and a fourth test pad on a primary surface of the second workpiece. The first and second workpieces are bonded along an interface between the primary surface of the first workpiece and the primary surface of the second workpiece to bond the first active pads with the second active pads, bond the first test pad with the third test pad, and bond the second test pad with the fourth test pad.
    Type: Application
    Filed: May 30, 2019
    Publication date: December 3, 2020
    Applicant: SanDisk Technologies LLC
    Inventors: Seungpil Lee, Kwang-Ho Kim
  • Publication number: 20190164616
    Abstract: A sense amplifier for a memory circuit that can sense into the deep negative voltage threshold region is described. A selected memory cell is sensed by discharging a source line through the memory cell into the bit line and sense amplifier. While discharging the source line through the memory cell into the sense amplifier, a voltage level on the discharge path is used to set the conductivity of a discharge transistor to a level corresponding to the conductivity of the selected memory cell. A sense node is then discharged through the discharge transistor. To reduce noise, a decoupling capacitor is connected to the control gate of the discharge transistor and an auxiliary keeper current is run through the discharge transistor.
    Type: Application
    Filed: June 1, 2018
    Publication date: May 30, 2019
    Applicant: SanDisk Technologies LLC
    Inventors: Hao Nguyen, Seungpil Lee
  • Publication number: 20190164581
    Abstract: Apparatuses, systems, and methods are disclosed for current sensing for non-volatile memory. A current to voltage conversion circuit may convert a current coupled to a sense amplifier to an analog voltage at a sense node. A voltage to digital conversion circuit may convert an analog voltage at a sense node to a digital signal, based on a voltage difference between the sense node and a comparison node during a strobe time. A bias circuit may bias a comparison node to a bias voltage other than a reference voltage, at least during a strobe time.
    Type: Application
    Filed: July 10, 2018
    Publication date: May 30, 2019
    Applicant: SanDisk Technologies LLC
    Inventors: HAO NGUYEN, GOPINATH BALAKRISHNAN, CHANG SIAU, SEUNGPIL LEE
  • Patent number: 10304550
    Abstract: A sense amplifier for a memory circuit that can sense into the deep negative voltage threshold region is described. A selected memory cell is sensed by discharging a source line through the memory cell into the bit line and sense amplifier. While discharging the source line through the memory cell into the sense amplifier, a voltage level on the discharge path is used to set the conductivity of a discharge transistor to a level corresponding to the conductivity of the selected memory cell. A sense node is then discharged through the discharge transistor. To reduce noise, a decoupling capacitor is connected to the control gate of the discharge transistor and an auxiliary keeper current is run through the discharge transistor.
    Type: Grant
    Filed: June 1, 2018
    Date of Patent: May 28, 2019
    Assignee: SanDisk Technologies LLC
    Inventors: Hao Nguyen, Seungpil Lee
  • Patent number: 9947407
    Abstract: In a non-volatile memory formed according to a NAND-type architecture that has, on one or both ends of the NAND strings, multiple select gates including some with programmable threshold voltages, a structure and corresponding for efficiently programming of such select gates. On the drain side, the end most of multiple drain select transistors is individually controllable and used for biasing purposes while one or more other drain side select gates are collectively programmed to set adjust their threshold voltage. Independently, on the source side, the end most of multiple source select transistors is individually controllable and used for biasing purposes while other source side select gates are collectively programmed to set adjust their threshold voltage.
    Type: Grant
    Filed: May 19, 2017
    Date of Patent: April 17, 2018
    Assignee: SanDisk Technologies LLC
    Inventors: Hao Nguyen, Man Mui, Khanh Nguyen, Seungpil Lee, Toru Ishigaki, Yingda Dong
  • Patent number: 9881676
    Abstract: Apparatuses, systems, and methods are disclosed for accessing non-volatile memory. A bit line is coupled to storage cells for a non-volatile memory element. A sense amplifier is coupled to a bit line. A sense amplifier includes a sense circuit and a bias circuit. A sense circuit senses an electrical property of a bit line for reading data from one or more storage cells, and a bias circuit applies a bias voltage to the bit line for writing data to one or more storage cells. A bias circuit and a sense circuit comprise separate parallel electrical paths within a sense amplifier.
    Type: Grant
    Filed: October 11, 2016
    Date of Patent: January 30, 2018
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Jong Hak Yuh, Raul Adrian Cernea, Seungpil Lee, Yen-Lung Jason Li, Qui Nguyen, Tai-Yuan Tseng, Cynthia Hsu
  • Publication number: 20170256317
    Abstract: In a non-volatile memory formed according to a NAND-type architecture that has, on one or both ends of the NAND strings, multiple select gates including some with programmable threshold voltages, a structure and corresponding for efficiently programming of such select gates. On the drain side, the end most of multiple drain select transistors is individually controllable and used for biasing purposes while one or more other drain side select gates are collectively programmed to set adjust their threshold voltage. Independently, on the source side, the end most of multiple source select transistors is individually controllable and used for biasing purposes while other source side select gates are collectively programmed to set adjust their threshold voltage.
    Type: Application
    Filed: May 19, 2017
    Publication date: September 7, 2017
    Applicant: SanDisk Technologies LLC
    Inventors: Hao Nguyen, Man Mui, Khanh Nguyen, Seungpil Lee, Toru Ishigaki, Yingda Dong
  • Patent number: 9659656
    Abstract: In a non-volatile memory formed according to a NAND-type architecture that has, on one or both ends of the NAND strings, multiple select gates including some with programmable threshold voltages, a structure and corresponding for efficiently programming of such select gates. On the drain side, the end most of multiple drain select transistors is individually controllable and used for biasing purposes while one or more other drain side select gates are collectively programmed to set adjust their threshold voltage. Independently, on the source side, the end most of multiple source select transistors is individually controllable and used for biasing purposes while other source side select gates are collectively programmed to set adjust their threshold voltage.
    Type: Grant
    Filed: March 7, 2016
    Date of Patent: May 23, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Hao Nguyen, Man Mui, Khanh Nguyen, Seungpil Lee, Toru Ishigaki, Yingda Dong
  • Patent number: 9633742
    Abstract: In non-volatile memory circuits, the amount of time needed for bit lines to settle can vary significantly depending on the location of the blocks selected. For example, in a sensing operation, the amount of time for bit lines to settle when being pre-charged by sense amplifiers will be shorter for blocks near the sense amps than for far side blocks. These variations can be particularly acute in high density memory structures, such as in 3D NAND memory, such as that of the BiCS variety. Rather than use the same timing for all blocks, the blocks can be segmented into groups based on their proximity to the sense amps. When performing a sensing operation, the timing can be adjusted based on the block group to which a selected page of memory cells belongs.
    Type: Grant
    Filed: July 10, 2014
    Date of Patent: April 25, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Amul Dhirajbhai Desai, Hao Nguyen, Seungpil Lee, Man Mui
  • Patent number: 9558836
    Abstract: A compact and versatile high speed sense amplifier suitable for use in non-volatile memory circuits is presented. The sense amp circuit is connected to first and second supply levels, a first level used for setting a program inhibit level on bit lines and a second level used for pre-charging bit lines for sensing operation. Outside of a data latch, the sense amp can employ only NMOS transistors. The arrangement of the circuit also allows for the discharging the bit line at the same time as transfers the sensing result out to other latches.
    Type: Grant
    Filed: September 14, 2015
    Date of Patent: January 31, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Man Lung Mui, Jongmin Park, Hao Thai Nguyen, Seungpil Lee
  • Publication number: 20160189778
    Abstract: In a non-volatile memory formed according to a NAND-type architecture that has, on one or both ends of the NAND strings, multiple select gates including some with programmable threshold voltages, a structure and corresponding for efficiently programming of such select gates. On the drain side, the end most of multiple drain select transistors is individually controllable and used for biasing purposes while one or more other drain side select gates are collectively programmed to set adjust their threshold voltage. Independently, on the source side, the end most of multiple source select transistors is individually controllable and used for biasing purposes while other source side select gates are collectively programmed to set adjust their threshold voltage.
    Type: Application
    Filed: March 7, 2016
    Publication date: June 30, 2016
    Applicant: SanDisk Technologies, Inc.
    Inventors: Hao NGUYEN, Man MUI, Khanh NGUYEN, Seungpil LEE, Toru ISHIGAKI, Yingda DONG
  • Patent number: 9361986
    Abstract: A non-volatile storage system is disclosed that includes non-volatile memory cells designed for high endurance and lower retention than other non-volatile memory cells.
    Type: Grant
    Filed: September 18, 2012
    Date of Patent: June 7, 2016
    Assignee: SanDisk Technologies Inc.
    Inventors: Jian Chen, Sergei Gorobets, Steven Sprouse, Tien-Chien Kuo, Yan Li, Seungpil Lee, Alex Mak, Deepanshu Dutta, Masaaki Higashitani
  • Patent number: 9318206
    Abstract: An erase process for a 3D stacked memory device allows a portion of a block of memory cells to be erased. In one approach, in a U-shaped NAND string configuration, memory cells in the drain- or source-side columns are erased. In another approach, such as in a U-shaped or a straight NAND string configuration, memory cells in a portion of a column of memory cells are erased, and a dummy memory cell is provided between the erased and non-erased memory cells. A dummy memory cell can be on either side (e.g., above and below) of an erase memory cell, or on either side of a non-erased memory cell. A dummy memory cell is ineligible to store user data, but prevents a downshift in the threshold voltage of an erased memory cell from changing the threshold voltage of a non-erased memory cell, due to capacitive coupling.
    Type: Grant
    Filed: November 10, 2014
    Date of Patent: April 19, 2016
    Assignee: SANDISK TECHNOLOGIES INC.
    Inventors: Yingda Dong, Alex Mak, Seungpil Lee, Johann Alsmeier
  • Patent number: 9305648
    Abstract: In a non-volatile memory formed according to a NAND-type architecture that has, on one or both ends of the NAND strings, multiple select gates including some with programmable threshold voltages, a structure and corresponding for efficiently programming of such select gates. On the drain side, the end most of multiple drain select transistors is individually controllable and used for biasing purposes while one or more other drain side select gates are collectively programmed to set adjust their threshold voltage. Independently, on the source side, the end most of multiple source select transistors is individually controllable and used for biasing purposes while other source side select gates are collectively programmed to set adjust their threshold voltage.
    Type: Grant
    Filed: August 20, 2014
    Date of Patent: April 5, 2016
    Assignee: SanDisk Technologies, Inc.
    Inventors: Hao Nguyen, Man Mui, Khanh Nguyen, Seungpil Lee, Toru Ishigaki, Yingda Dong
  • Patent number: 9293195
    Abstract: A compact and versatile high speed sense amplifier suitable for use in non-volatile memory circuits is presented. The sense amp includes a latch, which is connected to a data bus, and bit line selection circuitry by which it can selectively be connected to one or more bit lines. The sense amp also includes some intermediate circuitry having a first node connectable to a selected bit line through the bit line selection circuitry and a second node that is connectable to the latch circuit. The sense amp can include switches where the second node can be connected to either the value held in the latch or the inverse of the value held in the latch. The sense amp can also include a switch where an internal node of the sense amp can be connected directly to a voltage supply level.
    Type: Grant
    Filed: November 13, 2012
    Date of Patent: March 22, 2016
    Assignee: SanDisk Technologies Inc.
    Inventors: Man Lung Mui, Jongmin Park, Hao Thai Nguyen, Juan Carlos Lee, Seungpil Lee, Alexander Tsang-nam Chu
  • Publication number: 20160055911
    Abstract: In a non-volatile memory formed according to a NAND-type architecture that has, on one or both ends of the NAND strings, multiple select gates including some with programmable threshold voltages, a structure and corresponding for efficiently programming of such select gates. On the drain side, the end most of multiple drain select transistors is individually controllable and used for biasing purposes while one or more other drain side select gates are collectively programmed to set adjust their threshold voltage. Independently, on the source side, the end most of multiple source select transistors is individually controllable and used for biasing purposes while other source side select gates are collectively programmed to set adjust their threshold voltage.
    Type: Application
    Filed: August 20, 2014
    Publication date: February 25, 2016
    Inventors: Hao Nguyen, Man Mui, Khanh Nguyen, Seungpil Lee, Toru Ishigaki, Yingda Dong
  • Publication number: 20160035430
    Abstract: A compact and versatile high speed sense amplifier suitable for use in non-volatile memory circuits is presented. The sense amp circuit is connected to first and second supply levels, a first level used for setting a program inhibit level on bit lines and a second level used for pre-charging bit lines for sensing operation. Outside of a data latch, the sense amp can employ only NMOS transistors. The arrangement of the circuit also allows for the discharging the bit line at the same time as transfers the sensing result out to other latches.
    Type: Application
    Filed: September 14, 2015
    Publication date: February 4, 2016
    Inventors: Man Lung Mui, Jongmin Park, Hao Thai Nguyen, Seungpil Lee