Patents by Inventor Toshiaki Kirihata

Toshiaki Kirihata 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: 20020161967
    Abstract: A method for controlling the operation of a dynamic random access memory (DRAM) system, the DRAM system having a plurality of memory cells organized into rows and columns, is disclosed. In an exemplary embodiment of the invention, the method includes enabling a destructive read mode, the destructive read mode for destructively reading a bit of information stored within an addressed DRAM memory cell. The destructively read bit of information is temporarily stored into a temporary storage device. A delayed write back mode is enabled, the delayed write back mode for restoring the bit of information back to the addressed DRAM memory cell at a later time. The execution of the delayed write back mode is then scheduled, depending upon the availability of space within the temporary storage device.
    Type: Application
    Filed: April 26, 2001
    Publication date: October 31, 2002
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Toshiaki Kirihata, Sang Hoo Dhong, Hwa-Joon Oh, Matthew Wordeman
  • Publication number: 20020159319
    Abstract: A method for preparing a dynamic random access memory (DRAM) cell for a write operation with a preset condition is disclosed. In an exemplary embodiment, the method includes creating a preset voltage level within the cell prior to a delayed write back in a destructive read architecture, which preset voltage level has a value between a logic 0 voltage level and a logic 1 voltage level. The logic 0 voltage level corresponds to a first cell voltage value when the cell has a 0 bit stored therein, and the logic 1 voltage level corresponds to a second cell voltage value when the cell has a 1 bit stored therein. Prior to the creation of the preset voltage level within the cell, the cell has an initial voltage value corresponding to either the logic 0 voltage level or the logic 1 voltage level.
    Type: Application
    Filed: April 27, 2001
    Publication date: October 31, 2002
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Toshiaki Kirihata, Sang Hoo Dhong, Hwa-Joon Oh
  • Publication number: 20020108013
    Abstract: The invention is a selectable function that permits the address portion of data words to be separated from the storable content portion and that address portion to be used for different purposes without disturbing the stored contents in the memory array. The invention may be viewed as a command capability that permits analysis of signals for errors in such items as addresses, impedance calibration, timing, and component drift that develop in and between regions of an overall memory array.
    Type: Application
    Filed: February 6, 2002
    Publication date: August 8, 2002
    Inventors: Paul William Coteus, William Paul Hovis, William Wu Shen, Toshiaki Kirihata
  • Publication number: 20020089352
    Abstract: A dynamic logic circuit having reduced sub-threshold leakage current during standby mode comprises a connection to at least one upper power rail, a connection to a lower power rail, a precharge node, and an output node adapted to be charged to the potential of the upper power rail after a precharge signal is received at the precharge node. A latch on the output node is provided to maintain the potential at the output node, along with at least one input node for receiving at least one evaluation signal to maintain the potential at the output node to the voltage of the upper power rail or reduce the potential at the output node to the potential of the lower power rail. A device is coupled to the output node to set the output node to a potential which minimizes the sub-threshold leakage upon receipt of a standby signal to maintain the potential at the output node at the potential of the upper power rail or at the potential of the lower power rail.
    Type: Application
    Filed: January 11, 2001
    Publication date: July 11, 2002
    Applicant: International Business Machines Corporation
    Inventors: David R. Hanson, Toshiaki Kirihata, Gerhard Mueller
  • Publication number: 20020085405
    Abstract: A bitline architecture having bitlines with electrically controllable bitline lengths is described. The bitlines are provided with a switch which selectively couples or decouples local bitline segments of a bitline, depending on the need to execute the memory access. Bitlines with controllable bitline lengths can result in a reduction in power consumption without additional sense amplifiers or an additional metal layer.
    Type: Application
    Filed: December 28, 2000
    Publication date: July 4, 2002
    Inventors: Gerhard Mueller, Toshiaki Kirihata
  • Patent number: 6404264
    Abstract: A fuse latch for a memory circuit according to the present invention comprises a plurality of address lines, a control signal line provided from a fuse, a multiplexer for multiplexing the plurality of address lines in response to the control signal wherein the multiplexer has only one type transistors, and a decoder for receiving a multiplexed signal from the multiplexer. Since the multiplexer has a smaller size than that of a conventional CMOS multiplexer, a fuse latch circuit of the present invention has a smaller size than that of a conventional fuse latch. The multiplexer preferably has only NMOS transistors. To overcome a voltage drop due to an NMOS threshold voltage, the present invention uses low-threshold NMOSs and/or boosts the transistors in the multiplexer. Alternatively, the voltage drop is successfully converted into a CMOS level by using a dynamic logic circuit.
    Type: Grant
    Filed: December 6, 1999
    Date of Patent: June 11, 2002
    Assignees: Infineon Technologies North America Corp., International Business Machines Corporation
    Inventors: Gabriel Daniel, Toshiaki Kirihata
  • Patent number: 6404689
    Abstract: Hiding a refresh operation in a DRAM or eDRAM is achieved by tailoring an external random access time tRCext to slightly extend into the internal random access cycle time. This allows for an additional internal random access cycle time tRCint after a plurality of external random access cycles n(tRCext) when enabling the corresponding internal random access operation n(tRCint). The additional core random access cycle time tRCint is achieved at every nth clock, where n>tRCint/(tRCext−tRCint), or at a time defined by the product of tRCext and tRCint/(tRCext−tRCint). The additional core cycle time tRCint is used for refreshing the DRAM By scheduling a refresh-to-refresh period equal to or greater than the phase recovery time, a fully command compatible static random access time can be realized with DRAM cells.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: June 11, 2002
    Assignee: International Business Machines Corporation
    Inventors: Toshiaki Kirihata, Sang Hoo Dhong, Chorng-Lii Hwang
  • Patent number: 6400639
    Abstract: A memory decoder system is disclosed. In an exemplary embodiment of the invention, the system includes a matrix of memory cells, arranged into rows and columns, with a plurality of wordline drivers corresponding to each row in the matrix. A group of wordline driver-decoder blocks each contains a subset of the plurality of wordline drivers therein, with each of the wordline driver-decoder blocks being separated by a row control block. The row control block includes control circuitry for the wordline drivers. For any given wordline driver-decoder block, a first group of wordline drivers contained therein is controlled by a row control block located on one side of the given wordline driver-decoder block, while a second group of wordline drivers contained therein is controlled by a row control block located on an opposite side of the given wordline driver-decoder block.
    Type: Grant
    Filed: November 14, 2000
    Date of Patent: June 4, 2002
    Assignee: International Business Machines Corporation
    Inventors: Brian L. Ji, Toshiaki Kirihata, Dmitry G. Netis
  • Patent number: 6370055
    Abstract: There is provided a semiconductor memory having a plurality of memory units. The memory includes a plurality of read write drive (RWD) lines horizontally and/or vertically twisted such that the RWD lines are shared between the plurality of memory units. A plurality of columns is included in each of the plurality of memory units. Each of the plurality of columns is adapted to access the plurality of RWD lines through asymmetrical addressing.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: April 9, 2002
    Assignees: Infineon Technologies AG, International Business Machines Corporation
    Inventors: David Hanson, Gerhard Mueller, Toshiaki Kirihata
  • Publication number: 20020026556
    Abstract: A memory structure comprises a plurality of banks (each of the banks including a plurality of blocks) a plurality of timing critical address lines connected to all of the blocks in respective ones of the banks (a number of the critical address lines being equal to a number of the banks), and a plurality of dedicated address lines connected to respective ones of the blocks.
    Type: Application
    Filed: February 24, 1999
    Publication date: February 28, 2002
    Inventors: BRIAN JI, TOSHIAKI KIRIHATA, DMITRY NETIS
  • Patent number: 6338103
    Abstract: A circuit architecture and methodology for providing burst data transfer in high-speed digital circuit applications implements a sequence of overlapped global-pointer signals for generating corresponding sequence of non-overlapped local-pointer signals. One of the global pointer signals starts to be activated per cycle and the pulse width of each global pointer signal is greater than the burst cycle time. A global pointer signal <i> of a sequence (where i is one of the integers <1:n>) is used to generate a corresponding local pointer signal <i> that is reset by detecting a time at which the global pointer signal <i+1> starts to be activated. This allows for generation of reliable non-overlapped local pointer signals, while using overlapped global pointer signals. Each local generated pointer signal is used to accomplish a respective data transfer, e.g., from an individual latch to a single data line.
    Type: Grant
    Filed: March 24, 1999
    Date of Patent: January 8, 2002
    Assignee: International Business Machines Corporation
    Inventor: Toshiaki Kirihata
  • Publication number: 20020000867
    Abstract: A fuse latch for a memory circuit according to the present invention comprises a plurality of address lines, a control signal line provided from a fuse, a multiplexer for multiplexing the plurality of address lines in response to the control signal wherein the multiplexer has only one type transistors, and a decoder for receiving a multiplexed signal from the multiplexer. Since the multiplexer has a smaller size than that of a conventional CMOS multiplexer, a fuse latch circuit of the present invention has a smaller size than that of a conventional fuse latch. The multiplexer preferably has only NMOS transistors. To overcome a voltage drop due to an NMOS threshold voltage, the present invention uses low-threshold NMOSs and/or boosts the transistors in the multiplexer. Alternatively, the voltage drop is successfully converted into a CMOS level by using a dynamic logic circuit.
    Type: Application
    Filed: December 6, 1999
    Publication date: January 3, 2002
    Inventors: GABRIEL DANIEL, TOSHIAKI KIRIHATA
  • Patent number: 6335652
    Abstract: A semiconductor integrated circuit device including a redundant metal line for replacing a non-operational metal line for connecting to a circuit block. The invention further includes a method for decoupling a defective or otherwise non-operational conductive data line from a circuit block to which it is connected, and replacing the defective conductive data line with a redundant line by coupling it to the same circuit block. A spare conductive block is not needed. The redundant metal lines may be used in multiple levels of hierarchy within an integrated circuit device.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: January 1, 2002
    Assignee: International Business Machines Corporation
    Inventors: Gerhard Mueller, Toshiaki Kirihata
  • Patent number: 6326800
    Abstract: A method and apparatus for providing a self-adjusting burn-in test to a device-under-test by dynamically regulating critical burn-in test parameters, such as the supply voltage, and modifying the test conditions, avoiding in the process over and under burn-in. More specifically, the method includes setting an initial set of burn-in operating test conditions and repeatedly adjusting the burn-in operating test conditions while performing the burn-in test until a predetermined reliability target is achieved. The apparatus being described includes a test target, a tester, a reliability analyzer, and a burn-in controller. With this system, the number of fails are measured during burn-in, and the final number of fails after completion of the burn-in test is extrapolated. If the number of fails exceeds a stated reliability objective, the burn-in conditions specified by burn-in controller are reduced, thereby avoiding over burn-in or in the alternative under-burn.
    Type: Grant
    Filed: June 10, 1999
    Date of Patent: December 4, 2001
    Assignee: International Business Machines Corporation
    Inventor: Toshiaki Kirihata
  • Patent number: 6292402
    Abstract: A prefetch input write driver for a random access memory (RAM) and a RAM including the prefetch input write driver. The prefetch input write driver is especially for a synchronous dynamic RAM (SDRAM). The prefetch input write driver includes a data input stage receiving data, an enable stage receiving a corresponding data enable, and a write driver providing received data to a memory array in response to a write signal and the corresponding enable stage state. The data stage and the enable stage may each include two or more series connected three state drivers and a latch at the output of each three state driver. As data passes through the data stage a corresponding enable state is passed through the enable stage. Data is passed to the RAM array if the enable state indicates that data in the data stage is to be written into the array.
    Type: Grant
    Filed: December 8, 1999
    Date of Patent: September 18, 2001
    Assignee: International Business Machines Corporation
    Inventors: David R. Hanson, Toshiaki Kirihata, Gerhard Mueller
  • Patent number: 6288436
    Abstract: A plurality of fuses of different types, each type of fuse serving a specific purpose are positioned on a semiconductor integrated circuit wafer, wherein activating one type of fuse does not incapacitate fuses of a different type. Fuses of the first type, e.g., laser activated fuses, are primarily used for repairing defects at the wafer level, whereas fuses of the second type, e.g., electrically activated fuses, are used for repairing defects found after mounting the IC chips on a module and stressing the module at burn-in test. Defects at the module level typically are single cell failures which are cured by the electrically programmed fuses to activate module level redundancies.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: September 11, 2001
    Assignee: International Business Machines Corporation
    Inventors: Chandrasekhar Narayan, Kenneth Arndt, Toshiaki Kirihata, David Lachtrupp, Axel Brintzinger, Gabriel Daniel
  • Patent number: 6272062
    Abstract: There is provided a semiconductor memory device that includes: a plurality of memory cells arranged in at least two groups; at least one sense amplifier; a first and a second multiplexer; and at least one programmable control device. Each multiplexer is adapted to couple at least one of the groups to the amplifier. The programmable control device is adapted to control the first and said second multiplexers. In one embodiment, the programmable control device is adapted to control the multiplexers independently.
    Type: Grant
    Filed: May 31, 2000
    Date of Patent: August 7, 2001
    Assignee: Infineon Technologies AG
    Inventors: Gerhard Mueller, Toshiaki Kirihata, Dmitry Netis
  • Patent number: 6266272
    Abstract: A Partially Non-Volatile Dynamic Random Access Memory (PNDRAM) uses a DRAM array formed by a plurality of single transistor (1T) cells or two transistor (2T) cells. The cells are electrically programmable as a non-volatile memory. This results in a single chip design featuring both, a dynamic random access memory (DRAM) and an electrically programmable-read-only-memory (EPROM). The DRAM and the EPROM integrated in the PNDRAM can be easily reconfigured at any time, whether during manufacturing or in the field. The PNDRAM has multiple applications such as combining a main memory with ID, BIOS, or operating system information in a single chip.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: July 24, 2001
    Assignee: International Business Machines Corporation
    Inventors: Toshiaki Kirihata, Daniel Storaska, Chandrasekhar Narayan, William Tonti, Claude Bertin, Nick van Heel
  • Patent number: 6262615
    Abstract: A dynamic logic circuit having a charging circuit, comprising a first transistor having a first source/drain electrode adapted for coupling to a voltage supply and a second source/drain electrode connected to a node. The charging circuit couples the voltage supply to the node to place an initial charge on the node. A data transfer circuit is provided comprising a second transistor having a gate adapted for coupling to an input strobe pulse, a first source/drain electrode connected to the node, and a second source/drain electrode responsive to an input data and the input strobe pulse, for transferring the input data to the node to the node such that the pre-charged node is either discharged or remains depending on the input data. An output circuit is responsive to an output strobe pulse for coupling the data at the node to an output.
    Type: Grant
    Filed: February 25, 1999
    Date of Patent: July 17, 2001
    Assignees: Infineon Technologies AG, International Business Machines
    Inventors: Toshiaki Kirihata, Gerd Frankowsky
  • Patent number: 6259309
    Abstract: A semiconductor integrated circuit device including a redundant metal line for replacing a non-operational metal line for connecting to a circuit block. The invention further includes a method for decoupling a defective or otherwise non-operational conductive data line from a circuit block to which it is connected, and replacing the defective conductive data line with a redundant line by coupling it to the same circuit block. A spare conductive block is not needed. The redundant metal lines may be used in multiple levels of hierarchy within an integrated circuit device.
    Type: Grant
    Filed: May 5, 1999
    Date of Patent: July 10, 2001
    Assignees: International Business Machines Corporation, Siemens Microelectronics, Inc., SMI Holding LLC, Seimen Dram Semiconductor Corp., Infineon Technologies Corporation
    Inventors: Gerhard Mueller, Toshiaki Kirihata