Patents Examined by Michael Weinberg
  • Patent number: 7173854
    Abstract: Source line bias is an error introduced by a non-zero resistance in the ground loop of the read/write circuits. During sensing the source of a memory cell is erroneously biased by a voltage drop across the resistance and results in errors in the applied control gate and drain voltages. This error is minimized when the applied control gate and drain voltages have their reference point located as close as possible to the sources of the memory cells. In one preferred embodiment, the reference point is located at a node where the source control signal is applied. When a memory array is organized in pages of memory cells that are sensed in parallel, with the sources in each page coupled to a page source line, the reference point is selected to be at the page source line of a selected page via a multiplexor.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: February 6, 2007
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Siu Lung Chan
  • Patent number: 7173838
    Abstract: In accordance with the regions which are component elements of memory information (entry) and input information (comparison information or search key), quaternary information including a pair of the minimum value and the difference or ternary information including a pair of the data and the mask are used as I/O signals. In addition, in accordance with the two types of information, two types of encoding circuits and decoding circuits are disposed, and either one of the encoding circuits and the decoding circuits are activated in accordance with the values set to the registers disposed to designate the format of information in each region of the entry and the search key. By selecting the desired register from the plurality of registers in response to the external command signals and address signals, the encoding and decoding in accordance with the information to be processed are carried out.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: February 6, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Satoru Hanzawa, Tomonori Sekiguchi, Riichiro Takemura
  • Patent number: 7170783
    Abstract: A memory array including a first region in which a first memory sub-array is located and a second region separated from the first region in which a second memory sub-array is located. The first and second memory sub-arrays have flash memory cells coupled to a plurality of word lines. A driver region separates the first and second regions and includes word line driver circuits coupled to the word lines of the first and second memory sub-arrays. A row decoder region adjacent the first region and separate from the driver region includes at least some sub-circuits of row decoder circuits located therein. The row decoder circuits are coupled to the word line driver circuits located in the driver region and are configured to activate driver circuits to drive word lines of the first and second memory sub-arrays in response to decoding address signals selecting the particular row decoder circuit.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: January 30, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Chang Wan Ha, Ebrahim Abedifard
  • Patent number: 7170807
    Abstract: A data storage device such as a DRAM memory having a plurality of data storage cells 10 is disclosed. Each data storage cell 10 has a physical parameter which varies with time and represents one of two binary logic states. A selection circuit 16, writing circuits 18 and a refreshing circuit 22 apply input signals to the data storage cells to reverse the variation of the physical parameter with time of at least those cells representing one of the binary logic states by causing a different variation in the physical parameter of cells in one of said states than in the other.
    Type: Grant
    Filed: February 1, 2005
    Date of Patent: January 30, 2007
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 7170784
    Abstract: Source line bias is an error introduced by a non-zero resistance in the ground loop of the read/write circuits. During sensing the source of a memory cell is erroneously biased by a voltage drop across the resistance and results in errors in the applied control gate and drain voltages. This error is minimized when the applied control gate and drain voltages have their reference point located as close as possible to the sources of the memory cells. In one preferred embodiment, the reference point is located at a node where the source control signal is applied. When a memory array is organized in pages of memory cells that are sensed in parallel, with the sources in each page coupled to a page source line, the reference point is selected to be at the page source line of a selected page via a multiplexor.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: January 30, 2007
    Assignee: SanDisk Corporation
    Inventors: Raul-Adrian Cernea, Siu Lung Chan
  • Patent number: 7167392
    Abstract: A non-volatile memory (NVM) cell splits its basic function, i.e. program, erase, read and control, among a four PMOS transistor structure, allowing independent optimization of each function. The cell structure also includes an embedded static random access memory (SRAM) cell that utilizes a latch structure to preprogram data to be written to the cell. The programming method for the cell utilizes a reverse Fowler-Nordheim tunneling mechanism with a very small programming current, allowing an entire NVM array to be programmed at one cycle.
    Type: Grant
    Filed: July 15, 2005
    Date of Patent: January 23, 2007
    Assignee: National Semiconductor Corporation
    Inventors: Pavel Poplevine, Annie-Li-Keow Lum, Hengyang Lin, Andrew J. Franklin
  • Patent number: 7158402
    Abstract: An SRAM device comprising a column having opposing bit lines, asymmetric memory cells spanning the opposing bit lines in alternating orientations, and a sense amplifier. The sense amplifier includes sensing circuitry configured to sense values stored in the cells and switching circuitry configured to apply signals to the sensing circuitry as a function of the orientations.
    Type: Grant
    Filed: August 6, 2003
    Date of Patent: January 2, 2007
    Assignee: Texas Instruments Incorporated
    Inventor: Theodore W. Houston
  • Patent number: 7154808
    Abstract: A semiconductor memory device comprises a plurality of cell blocks, block controllers for activating or precharging word lines of each of the cell blocks according to an external active command and a precharge command, a sense amplifier for sensing a fine voltage shared by bit lines and complementary bit lines of the cell blocks, sense amplifier controllers for activating or precharging the sense amplifier according to the external active command and the precharge command, and outputting bit line isolation signals that control the connection between the sense amplifier and the cell block, a block address decoder for decoding external block addresses in normal mode to output a block select signal for selecting one cell block, and outputting a block select signal for selecting even or odd cell blocks according to one of the external block addresses in test mode, and a SES control block for outputting a bit line isolation control signal for controlling the bit line isolation signals and a sense amplifier enable
    Type: Grant
    Filed: May 9, 2005
    Date of Patent: December 26, 2006
    Assignee: Hynix Semiconductor Inc.
    Inventor: Young Bo Shim
  • Patent number: 7154795
    Abstract: A precharge initiated dynamic random access memory (DRAM) technique of especial utility with respect to DRAM devices and other integrated circuit devices incorporating embedded DRAM in which the rising edge of each clock initiates a precharge to those subarrays that were active as opposed to conventional techniques wherein the subarrays are typically precharged so that they are made ready on the rising edge of the clock, which would then start an active cycle. The longer restore time that is achieved can be used to enable the establishment of better logic “1” and “0” levels in the memory cells, to reduce the device clock period and/or to enable other functions to be performed in parallel with the precharge function.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: December 26, 2006
    Assignees: United Memories, Inc., Sony Corporation
    Inventors: Michael C. Parris, Kim C. Hardee
  • Patent number: 7145807
    Abstract: A method is provided for operating an electrical writable and erasable memory cell, which has a channel region that can be operated in a first and a second direction, wherein information is stored as the difference of an effective parameter.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: December 5, 2006
    Assignee: Infineon Technologies AG
    Inventors: Joachim Deppe, Mark Isler, Christoph Ludwig, Jens-Uwe Sachse, Jan-Malte Schley, Ricardo Pablo Mikalo
  • Patent number: 7142465
    Abstract: A semiconductor memory in which a drop in the potential of a bit line due to coupling capacitance at the time of writing data can be restored in a space-saving way without increasing a load at read time. In response to a selection signal, a selection circuit selects complementary bit lines and connects the selected complementary bit lines to write data bus lines or read data bus lines. When data is written, a voltage boosting circuit section selects a read data bus line connected to a bit line of the pair of complementary bit lines located opposite to a bit line the potential of which is decreased on the basis of the data to be written and raises the potential of the selected read data bus line. As a result, a potential level which has dropped due to coupling capacitance between the bit lines can be restored.
    Type: Grant
    Filed: March 8, 2005
    Date of Patent: November 28, 2006
    Assignee: Fujitsu Limited
    Inventor: Tsuyoshi Kodama
  • Patent number: 7126862
    Abstract: A decoder for a memory device includes driving devices each applying a respective line voltage to a respective line of the memory device when turned on. The decoder also includes a control device coupled to the plurality of driving devices at a common node for generating a voltage that controls the driving devices to turn on or off. Also, a capacitor coupled to the common node increases the voltage at the common node from an initial boost voltage to a final boost voltage. Thus, a line of a memory device is driven to a boost voltage with minimized area and wiring complexity.
    Type: Grant
    Filed: March 8, 2005
    Date of Patent: October 24, 2006
    Assignee: Spansion LLC
    Inventor: Takao Akaogi
  • Patent number: 7126840
    Abstract: A ferroelectric memory device that has a first bit line and a first plate line includes a first ferroelectric capacitor group having a plurality of ferroelectric capacitors coupled in series and in a ring shape. A switching means switches whether a ferroelectric capacitor out of the first ferroelectric capacitor group is electrically coupled to the first bit line and the first plate line.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: October 24, 2006
    Assignee: Seiko Epson Corporation
    Inventor: Mitsuhiro Yamamura
  • Patent number: 7120063
    Abstract: Flash memory cells are presented which comprise a dielectric material formed above a substrate channel region, a charge trapping material formed over the dielectric material, and a control gate formed over the charge trapping material. The cell may be programmed by directing electrons from the control gate into the charge trapping material to raise the cell threshold voltage. The electrons may be directed from the control gate to the charge trapping material by coupling a substrate to a substrate voltage potential, and coupling the control gate to a gate voltage potential, where the gate voltage potential is lower than the substrate voltage potential. The cell may be erased by directing electrons from the charge trapping material into the control gate to lower a threshold voltage of the flash memory cell, such as by coupling the substrate to a substrate voltage potential, and coupling the control gate to a gate voltage potential, where the gate voltage potential is higher than the substrate voltage potential.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: October 10, 2006
    Assignee: Spansion LLC
    Inventors: Zhizheng Liu, Zengtao Liu, Yi He, Mark Randolph
  • Patent number: 7099178
    Abstract: A ferromagnetic random access memory includes a first and second blocks. Each of the first and second blocks includes a switch transistor and memory cells connected in series between a first and second end. The memory cell includes a ferromagnetic capacitor and a cell transistor connected in parallel. A first plate line is connected to each of the first end of the first and second blocks. A first block selection transistor includes a current path one end of which is connected to the second end of the first block. A second block selection transistor includes a current path one end of which is connected to the second end of the second block. A first bit line is connected to each of another end of the current path in the first and second block selection transistors.
    Type: Grant
    Filed: November 15, 2004
    Date of Patent: August 29, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shinichiro Shiratake
  • Patent number: 7042763
    Abstract: A method of selectively programming nonvolatile memory cells in which multiple programming voltages are used to obtain the desired voltage on the storage nodes of the cells selected for programming, while the storage nodes of unselected cells remain undisturbed.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: May 9, 2006
    Assignee: National Semiconductor Corporation
    Inventors: Yuri Mirgorodski, Pavel Poplevine, Peter J. Hopper, Andrew J. Franklin
  • Patent number: 7035141
    Abstract: The present memory structure includes thereof a first conductor, a second conductor, a resistive memory cell connected to the second conductor, a first diode connected to the resistive memory cell and the first conductor, and oriented in the forward direction from the resistive memory cell to the first conductor, and a second diode connected to the resistive memory cell and the first conductor, in parallel with the first diode, and oriented in the reverse direction from the resistive memory cell to the first conductor. The first and second diodes have different threshold voltages.
    Type: Grant
    Filed: November 17, 2004
    Date of Patent: April 25, 2006
    Inventors: Nicholas H. Tripsas, Colin S. Bill, Michael A. VanBuskirk, Matthew Buynoski, Tzu-Ning Fang, Wei Daisy Cai, Suzette Pangrle, Steven Avanzino