Patents by Inventor Fanglin Zhang

Fanglin Zhang 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: 20140036601
    Abstract: A non-volatile storage system that performs programming and reading processes. The programming process includes coarse/fine programming and verify operations. Programming is verified by testing for two different threshold voltage levels while applying the same voltage level to the control gate of a memory cell by testing for current levels through the memory cells and adjusting the current levels tested for based on current temperature such that the difference between the two effective tested threshold voltage levels remains constant over temperature variation.
    Type: Application
    Filed: October 7, 2013
    Publication date: February 6, 2014
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Ken Oowada, Yingda Dong, Gerrit Jan Hemink, Man Lung Mui, Hao Nguyen, Seungpil Lee, Jong Park, Fanglin Zhang
  • Patent number: 8582381
    Abstract: A non-volatile storage system that performs programming and reading processes. The programming process includes coarse/fine programming and verify operations. Programming is verified by testing for two different threshold voltage levels while applying the same voltage level to the control gate of a memory cell by testing for current levels through the memory cells and adjusting the current levels tested for based on current temperature such that the difference between the two effective tested threshold voltage levels remains constant over temperature variation.
    Type: Grant
    Filed: February 23, 2012
    Date of Patent: November 12, 2013
    Assignee: Sandisk Technologies, Inc.
    Inventors: Ken Oowada, Yingda Dong, Gerrit Jan Hemink, Man Lung Mui, Hao Nguyen, Seungpil Lee, Jong Park, Fanglin Zhang
  • Publication number: 20130223155
    Abstract: A non-volatile storage system that performs programming and reading processes. The programming process includes coarse/fine programming and verify operations. Programming is verified by testing for two different threshold voltage levels while applying the same voltage level to the control gate of a memory cell by testing for current levels through the memory cells and adjusting the current levels tested for based on current temperature such that the difference between the two effective tested threshold voltage levels remains constant over temperature variation.
    Type: Application
    Filed: February 23, 2012
    Publication date: August 29, 2013
    Inventors: Ken Oowada, Yingda Dong, Gerrit Jan Hemink, Man Lung Mui, Hao Nguyen, Seungpil Lee, Jong Park, Fanglin Zhang
  • Patent number: 8169831
    Abstract: Sensing circuits for sensing a conduction current of a memory cell among a group of non-volatile memory cells being sensed in parallel and providing the result thereof to a data bus are presented. A precharge circuit is coupled to a node for charging the node to an initial voltage. An intermediate circuit is also coupled to the node and connectable to the memory cell, whereby current from the precharge circuit can be supplied to the memory cell. The circuit also includes a comparator circuit to perform a determination the conduction current by a rate of discharge at the node; a data latch coupled to the comparator circuit to hold the result of said determination; and a transfer gate coupled to the data latch to supply a result latched therein to the data bus independently of the node. This arrangement improves sensing performance and can help to eliminate noise on the analog sensing path during sensing and reduce switching current.
    Type: Grant
    Filed: May 3, 2011
    Date of Patent: May 1, 2012
    Assignee: SanDisk Technologies Inc.
    Inventors: Hao Thai Nguyen, Man Lung Mui, Seungpil Lee, Fanglin Zhang, Chi-Ming Wang
  • Publication number: 20110205804
    Abstract: Sensing circuits for sensing a conduction current of a memory cell among a group of non-volatile memory cells being sensed in parallel and providing the result thereof to a data bus are presented. A precharge circuit is coupled to a node for charging the node to an initial voltage. An intermediate circuit is also coupled to the node and connectable to the memory cell, whereby current from the precharge circuit can be supplied to the memory cell. The circuit also includes a comparator circuit to perform a determination the conduction current by a rate of discharge at the node; a data latch coupled to the comparator circuit to hold the result of said determination; and a transfer gate coupled to the data latch to supply a result latched therein to the data bus independently of the node. This arrangement improves sensing performance and can help to eliminate noise on the analog sensing path during sensing and reduce switching current.
    Type: Application
    Filed: May 3, 2011
    Publication date: August 25, 2011
    Inventors: Hao Thai Nguyen, Man Lung Mui, Seungpil Lee, Fanglin Zhang, Chi-Ming Wang
  • Patent number: 7974134
    Abstract: In a non-volatile memory system, a voltage generator provides a voltage to a gate of a voltage-setting transistor which is used in a sense circuit to set an initial voltage at a sense node. At the end of a sense period, a final voltage of the sense node is compared to a trip point, which is the threshold voltage of a voltage-sensing transistor. To account for temperature variations and manufacturing process variations, the voltage generator includes a transistor which is matched to the voltage-setting transistor, and a transistor which is matched to the voltage-sensing transistor. As a result, a voltage swing between the initial voltage and the trip point is constant, even as the initial voltage and trip point vary. In a particular implementation, the voltage generator uses a cascode current mirror circuit, and receives a reference current from a band gap voltage circuit.
    Type: Grant
    Filed: November 13, 2009
    Date of Patent: July 5, 2011
    Assignee: SanDisk Technologies Inc.
    Inventors: Fanglin Zhang, Jong Park, Man Mui, Alexander Chu, Seungpil Lee
  • Patent number: 7957197
    Abstract: Sensing circuits for sensing a conduction current of a memory cell among a group of non-volatile memory cells being sensed in parallel and providing the result of the sensing to a data bus are presented. A precharge circuit is coupled to a node for charging the node to an initial voltage. An intermediate circuit is also coupled to the node and connectable to the memory cell, by which current from the precharge circuit can be supplied to the memory cell. The circuit also includes a comparator circuit to perform a determination of the conduction current by a rate of discharge at the node; a data latch coupled to the comparator circuit to hold the result of this determination; and a transfer gate coupled to the data latch to supply a latched result to the data bus independently of the node. This arrangement improves sensing performance and can help to eliminate noise on the analog sensing path during sensing and reduce switching current.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: June 7, 2011
    Assignee: SanDisk Corporation
    Inventors: Hao Thai Nguyen, Man Lung Mui, Seungpil Lee, Fanglin Zhang, Chi-Ming Wang
  • Publication number: 20110116320
    Abstract: In a non-volatile memory system, a voltage generator provides a voltage to a gate of a voltage-setting transistor which is used in a sense circuit to set an initial voltage at a sense node. At the end of a sense period, a final voltage of the sense node is compared to a trip point, which is the threshold voltage of a voltage-sensing transistor. To account for temperature variations and manufacturing process variations, the voltage generator includes a transistor which is matched to the voltage-setting transistor, and a transistor which is matched to the voltage-sensing transistor. As a result, a voltage swing between the initial voltage and the trip point is constant, even as the initial voltage and trip point vary. In a particular implementation, the voltage generator uses a cascode current mirror circuit, and receives a reference current from a band gap voltage circuit.
    Type: Application
    Filed: November 13, 2009
    Publication date: May 19, 2011
    Inventors: Fanglin Zhang, Jong Park, Man Mui, Alexander Chu, Seungpil Lee
  • Publication number: 20090296488
    Abstract: Sensing circuits for sensing a conduction current of a memory cell among a group of non-volatile memory cells being sensed in parallel and providing the result thereof to a data bus are presented. A precharge circuit is coupled to a node for charging the node to an initial voltage. An intermediate circuit is also coupled to the node and connectable to the memory cell, whereby current from the precharge circuit can be supplied to the memory cell. The circuit also includes a comparator circuit to perform a determination the conduction current by a rate of discharge at the node; a data latch coupled to the comparator circuit to hold the result of said determination; and a transfer gate coupled to the data latch to supply a result latched therein to the data bus independently of the node. This arrangement improves sensing performance and can help to eliminate noise on the analog sensing path during sensing and reduce switching current.
    Type: Application
    Filed: May 28, 2008
    Publication date: December 3, 2009
    Inventors: Hao Thai Nguyen, Man Lung Mui, Seungpil Lee, Fanglin Zhang, Chi-Ming Wang
  • Patent number: 7474561
    Abstract: The lowest programmed state in multi-state non-volatile flash memory devices can suffer from an increased level of bit line to bit line capacitive charge coupling when compared with other states. Program voltages applied to memory cells as increasing voltage pulses can be incremented using smaller values when programming memory cells to the lowest programmable state. Smaller increments in the applied voltage allow for greater precision and a narrower threshold voltage distribution to compensate for the disproportionate charge coupling experienced by cells programmed to this state. Smaller increment values can be used when switching from lower page to upper page programming in some implementations.
    Type: Grant
    Filed: October 10, 2006
    Date of Patent: January 6, 2009
    Assignee: SanDisk Corporation
    Inventors: Yan Li, Fanglin Zhang, Toru Miwa, Farookh Moogat
  • Patent number: 7450426
    Abstract: The lowest programmed state in multi-state non-volatile flash memory devices can suffer from an increased level of bit line to bit line capacitive charge coupling when compared with other states. Program voltages applied to memory cells as increasing voltage pulses can be incremented using smaller values when programming memory cells to the lowest programmable state. Smaller increments in the applied voltage allow for greater precision and a narrower threshold voltage distribution to compensate for the disproportionate charge coupling experienced by cells programmed to this state. Smaller increment values can be used when switching from lower page to upper page programming in some implementations.
    Type: Grant
    Filed: October 10, 2006
    Date of Patent: November 11, 2008
    Assignee: SanDisk Corporation
    Inventors: Yan Li, Fanglin Zhang, Toru Miwa, Farookh Moogat
  • Publication number: 20080084751
    Abstract: The lowest programmed state in multi-state non-volatile flash memory devices can suffer from an increased level of bit line to bit line capacitive charge coupling when compared with other states. Program voltages applied to memory cells as increasing voltage pulses can be incremented using smaller values when programming memory cells to the lowest programmable state. Smaller increments in the applied voltage allow for greater precision and a narrower threshold voltage distribution to compensate for the disproportionate charge coupling experienced by cells programmed to this state. Smaller increment values can be used when switching from lower page to upper page programming in some implementations.
    Type: Application
    Filed: October 10, 2006
    Publication date: April 10, 2008
    Inventors: Yan Li, Fanglin Zhang, Toru Miwa, Farookh Moogat
  • Publication number: 20080084752
    Abstract: The lowest programmed state in multi-state non-volatile flash memory devices can suffer from an increased level of bit line to bit line capacitive charge coupling when compared with other states. Program voltages applied to memory cells as increasing voltage pulses can be incremented using smaller values when programming memory cells to the lowest programmable state. Smaller increments in the applied voltage allow for greater precision and a narrower threshold voltage distribution to compensate for the disproportionate charge coupling experienced by cells programmed to this state. Smaller increment values can be used when switching from lower page to upper page programming in some implementations.
    Type: Application
    Filed: October 10, 2006
    Publication date: April 10, 2008
    Inventors: Yan Li, Fanglin Zhang, Toru Miwa, Farookh Moogat