Patents by Inventor Kulachet Tanpairoj

Kulachet Tanpairoj 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: 8750045
    Abstract: In a non-volatile memory device, the parameters used in write and erase operation are varied based upon device age. For example, in a programming operation using a staircase waveform, the amplitude of the initial pulse can be adjusted based upon the number of erase-program cycles (hot count) of the block containing the selected physical page for the write. This arrangement can preserve performance for relatively fresh devices, while extending life as a devices ages by using gentler waveforms as the device ages.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: June 10, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Jianmin Huang, Kulachet Tanpairoj, Chris Nga Yee Avila, Gautam Ashok Dusija
  • Publication number: 20140029342
    Abstract: In a non-volatile memory device, the parameters used in write and erase operation are varied based upon device age. For example, in a programming operation using a staircase waveform, the amplitude of the initial pulse can be adjusted based upon the number of erase-program cycles (hot count) of the block containing the selected physical page for the write. This arrangement can preserve performance for relatively fresh devices, while extending life as a devices ages by using gentler waveforms as the device ages.
    Type: Application
    Filed: July 27, 2012
    Publication date: January 30, 2014
    Applicant: SanDisk Technologies Inc.
    Inventors: Jianmin Huang, Kulachet Tanpairoj, Chris Nga Yee Avila, Gautam Ahok Dusija
  • Patent number: 7656705
    Abstract: Methods of rapidly programming a wordline of multi-level flash memory cells comprising memory cell element-pairs having three or more data levels per bit or element corresponding to three or more threshold voltages are provided. An interactive program algorithm rapidly programs the elements of the wordline of memory cells in a learn phase and a single core programming phase. In one embodiment, each wordline comprises learn element-pairs first programmed to provide learn drain voltages for programming core element-pairs along the wordline having the same program pattern of data levels. A set comprising one or more program patterns is chosen to correspond with each program level used on the wordline. The learn element-pairs are programmed to determine a learned program drain voltage for each program level. This learned program drain voltage essentially provides a wordline and program level specific program characterization of the Vd required for the remaining elements of that wordline.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: February 2, 2010
    Assignee: Spansion LLC
    Inventors: Darlene Hamilton, Fatima Bathul, Kulachet Tanpairoj, Ou Li
  • Patent number: 7652919
    Abstract: The claimed subject matter provides systems and/or methods that facilitate programming and reading multi-level, multi-bit memory cells in a memory device. In multi-bit memory cells, programming one element can affect the second element. Certain combinations of elements can cause excessive levels of complementary bit disturb, state dependent non-uniform charge loss, and state dependent program disturb, reducing memory device reliability. Such effects may be pronounced where a high charge level is programmed into a first element while a second element of the same memory cell is unprogrammed. Memory cell elements can be programmed using additional charge levels to mitigate such effects.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: January 26, 2010
    Assignee: Spansion LLC
    Inventors: Darlene G. Hamilton, Kulachet Tanpairoj, Fatima Bathul, Ou Li
  • Publication number: 20090103357
    Abstract: Methods of rapidly programming a wordline of multi-level flash memory cells comprising memory cell element-pairs having three or more data levels per bit or element corresponding to three or more threshold voltages are provided. An interactive program algorithm rapidly programs the elements of the wordline of memory cells in a learn phase and a single core programming phase. In one embodiment, each wordline comprises learn element-pairs first programmed to provide learn drain voltages for programming core element-pairs along the wordline having the same program pattern of data levels. A set comprising one or more program patterns is chosen to correspond with each program level used on the wordline. The learn element-pairs are programmed to determine a learned program drain voltage for each program level. This learned program drain voltage essentially provides a wordline and program level specific program characterization of the Vd required for the remaining elements of that wordline.
    Type: Application
    Filed: October 17, 2007
    Publication date: April 23, 2009
    Inventors: Darlene Hamilton, Fatima Bathul, Kulachet Tanpairoj, Ou Li
  • Publication number: 20080158954
    Abstract: The claimed subject matter provides systems and/or methods that facilitate programming and reading multi-level, multi-bit memory cells in a memory device. In multi-bit memory cells, programming one element can affect the second element. Certain combinations of elements can cause excessive levels of complementary bit disturb, state dependent non-uniform charge loss, and state dependent program disturb, reducing memory device reliability. Such effects may be pronounced where a high charge level is programmed into a first element while a second element of the same memory cell is unprogrammed. Memory cell elements can be programmed using additional charge levels to mitigate such effects.
    Type: Application
    Filed: June 29, 2007
    Publication date: July 3, 2008
    Applicant: SPANSION LLC
    Inventors: Darlene G. Hamilton, Fatima Bathul, Kulachet Tanpairoj, Ou Li
  • Patent number: 6967873
    Abstract: A method of erasing a flash electrically erasable read only memory (EEPROM) device composed of a plurality of memory cells includes pre-programming the plurality of memory cells, applying an erase pulse to the plurality of memory cells followed by an erase verification. The erase verification is followed by soft programming any memory cells having a threshold voltage below a predetermined minimum level and applying a positive gate stress to the plurality of memory cells. The erase method prevents overerasing and provides a tightened threshold voltage distribution.
    Type: Grant
    Filed: October 2, 2003
    Date of Patent: November 22, 2005
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Zhizheng Liu, Mark W. Randolph, Yi He, Edward Hsia, Kulachet Tanpairoj, Mimi Lee, Alykhan Madhani
  • Patent number: 6956768
    Abstract: A method of programming a multi-level, dual cell memory device. The method includes independently programming a first charge storing cell and a second charge storing cell to respective data states, the data states selected from a blank program level or one of a plurality of charged program levels. Also disclosed is a method of reading the multi-level, dual cell memory device using a plurality of reference currents.
    Type: Grant
    Filed: April 15, 2003
    Date of Patent: October 18, 2005
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Kulachet Tanpairoj, Edward Hsia, Yi He
  • Publication number: 20050073886
    Abstract: A method of erasing a flash electrically erasable read only memory (EEPROM) device composed of a plurality of memory cells includes pre-programming the plurality of memory cells, applying an erase pulse to the plurality of memory cells followed by an erase verification. The erase verification is followed by soft programming any memory cells having a threshold voltage below a predetermined minimum level and applying a positive gate stress to the plurality of memory cells. The erase method prevents overerasing and provides a tightened threshold voltage distribution.
    Type: Application
    Filed: October 2, 2003
    Publication date: April 7, 2005
    Inventors: Darlene Hamilton, Zhizheng Liu, Mark Randolph, Yi He, Edward Hsia, Kulachet Tanpairoj, Mimi Lee, Alykhan Madhani
  • Patent number: 6822909
    Abstract: A method of programming a dual cell memory device having a first charge storing cell and a second charge storing cell. The method can include applying an initial program pulse to the memory device; comparing the threshold voltage of the memory device with a verify threshold voltage; and if the threshold voltage of the memory device is less than the verify threshold voltage, applying a second program pulse to the memory device during which at least one condition of the second program pulse is modified from the initial program pulse.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: November 23, 2004
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Edward Hsia, Mark W. Randolph, Edward F. Runnion, Kulachet Tanpairoj
  • Patent number: 6813752
    Abstract: A method of determining charge loss activation for a memory array. Memory arrays are programmed with a pattern for testing charge loss. Then, respective bake times are calculated for the memory arrays to experience a given amount of charge loss at their respective bake temperatures. Then, charge loss activation energy is calculated, based on the respective bake times. In one version, the memory arrays are cycled by repeatedly erasing and reprogramming them before baking. In another embodiment, various regions of the memory arrays are programmed to a plurality of distinct delta threshold voltages before baking.
    Type: Grant
    Filed: November 26, 2002
    Date of Patent: November 2, 2004
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Edward Hsia, Darlene G. Hamilton, Wei Zheng, Mark W. Randolph, Kulachet Tanpairoj
  • Publication number: 20040208057
    Abstract: A method of programming a multi-level, dual cell memory device. The method includes independently programming a first charge storing cell and a second charge storing cell to respective data states, the data states selected from a blank program level or one of a plurality of charged program levels. Also disclosed is a method of reading the multi-level, dual cell memory device using a plurality of reference currents.
    Type: Application
    Filed: April 15, 2003
    Publication date: October 21, 2004
    Inventors: Darlene G. Hamilton, Kulachet Tanpairoj, Edward Hsia, Yi He
  • Patent number: 6778442
    Abstract: A method of programming a dual cell memory device having a first charge storing cell and a second charge storing cell. According to one aspect of the method, the method can include over-erasing the first and second charge storing cells to shift an erase state threshold voltage of the memory device to be lower than a natural state threshold voltage. According to another aspect of the method, the method can include programming the first and second charge storing cells to the same data state and verifying that the second programmed charge storing cell stores charge corresponding to the data state. If the verification fails, both charge storing cells can be re-pulsed.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: August 17, 2004
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Edward Hsia, Kulachet Tanpairoj, Alykhan Madhani, Mimi Lee
  • Patent number: 6775187
    Abstract: A method of programming a dual cell memory device having a first charge storing cell and second charge storing cell. The first charge storing cell can be pre-read to determine if the first charge storing cell stores an amount of charge to increase a threshold voltage of the memory device over a specified threshold voltage. If not, the second charge storing cell can be programmed with a standard program pulse. If so, the second charge storing cell can be programed with a modified program pulse.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: August 10, 2004
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Edward F. Runnion, Edward Hsia, Kulachet Tanpairoj
  • Patent number: 6768673
    Abstract: A method of programming and reading a dual cell memory device. The method includes storing a selected program level in each cell and reading one of the cells to determine a single data value stored by the memory device.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: July 27, 2004
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Edward Hsia, Darlene Hamilton, Kulachet Tanpairoj, Mimi Lee, Alykhan F. Madhani, Yi He
  • Publication number: 20030218913
    Abstract: A method of erasing a sector of flash memory cells wherein a first set of preset pre-erase voltages is applied to the sector of flash memory cells. After the first set of preset pre-erase voltages is applied it is determined if another set of preset pre-erase voltages is to be applied to the sector of flash memory cells. If another set of preset pre-erase voltages is applied and if another set of preset pre-erase set of pre-erase voltages is not to be applied, a standard erase routine is applied to the sector.
    Type: Application
    Filed: May 24, 2002
    Publication date: November 27, 2003
    Inventors: Binh Quang Le, Darlene Hamilton, Kulachet Tanpairoj, Zhizheng Liu, Yi He, Wei Zheng, Pau-Ling Chen, Michael Vanbuskirk
  • Patent number: 6590811
    Abstract: A method and system for programming of the normal bits of a memory array of dual bit memory cells is accomplished by programming at a substantially high delta VT. The substantially higher VT assures that the memory array will maintain programmed data and erase data consistently after higher temperature stresses and/or customer operation over substantial periods of time. Furthermore, by utilizing substantially high gate and drain voltages during programming, programming times are kept short without degrading charge loss. A methodology is provided that determines the charge loss for single bit operation during program and erase cycles. The charge losses over cycling and stress are then utilized to determine an appropriate delta VT to be programmed into a command logic and state machine.
    Type: Grant
    Filed: June 17, 2002
    Date of Patent: July 8, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Narbeh Derhacobian, Janet S. Y. Wang, Kulachet Tanpairoj
  • Patent number: 6512701
    Abstract: A system and methodology is provided for verifying erasure of one or more dual bit virtual ground memory cells in a memory device, such as a flash memory. Each of the dual bits have a first or normal bit and a second or complimentary bit associated with the first or normal bit. The system and methodology include verifying and erasure of both a normal bit and a complimentary bit of the cell. The erasure includes applying a set of erase pulses to the normal bit and complimentary bit in a single dual bit cell. The set of erase pulses is comprised of a two sided erase pulse to both sides of the bits in the cell or transistor junction followed by a first single sided erase pulse to one side and a second single sided erase pulse to the other side of transistor junction.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: January 28, 2003
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Kulachet Tanpairoj, Yider Wu
  • Patent number: 6493261
    Abstract: Dummy columns of memory cells formed during fabrication outside edge columns are connected to the actual used memory cells of sectors or the like. The columns of dummy memory cells are compensated by floating the dummy memory cells during normal programming and erase cycles, or alternatively, by programming and erasing the dummy memory cells along with the actual used memory cells in the sector. By treating the dummy memory cells similar to the actual used cells, charge that leaks into the dummy cells during fabrication and normal operation that has deleterious effects at higher stress temperatures and/or due to the longevity of customer operation is substantially eliminated.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: December 10, 2002
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Darlene G. Hamilton, Kulachet Tanpairoj, Ravi Sunkavalli, Narbeh Derhacobian, Michael A. Van Buskirk
  • Publication number: 20020159293
    Abstract: A method and system for programming of the normal bits of a memory array of dual bit memory cells is accomplished by programming at a substantially high delta VT. The substantially higher VT assures that the memory array will maintain programmed data and erase data consistently after higher temperature stresses and/or customer operation over substantial periods of time. Furthermore, by utilizing substantially high gate and drain voltages during programming, programming times are kept short without degrading charge loss. A methodology is provided that determines the charge loss for single bit operation during program and erase cycles. The charge losses over cycling and stress are then utilized to determine an appropriate delta VT to be programmed into a command logic and state machine.
    Type: Application
    Filed: February 28, 2001
    Publication date: October 31, 2002
    Inventors: Darlene G. Hamilton, Narbeh Derhacobian, Janet S. Y. Wang, Kulachet Tanpairoj