Patents by Inventor Takeshi Hamamoto

Takeshi Hamamoto 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: 5319589
    Abstract: A bit line control circuit is disclosed for implementing a dynamic content addressable memory. The bit line control circuit includes a read circuit 12 and a first write circuit 13 connected to data line pairs DT, /DT, a sense amplifier 14, a bit line discharge circuit 15, a bit line charge circuit 16, a transfer gate circuit 17, and a second write circuit 18. The bit line control circuit is connected to a CAM cell array through bit lines BLa, /BLa. Various operations such as write, read, refresh and match detection and the like necessary in the dynamic associative memory can be implemented under simple timing control by a simple circuit configuration.
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: June 7, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tadato Yamagata, Masaaki Mihara, Takeshi Hamamoto, Hideyuki Ozaki
  • Patent number: 5299283
    Abstract: A device for executing fuzzy inference includes a first storage area constituting a condition portion of a fuzzy set and a second storage area constituting a conclusion portion of the fuzzy set. The first storage area stores membership functions of the condition portion in order to develop a first bit mapping while the second storage area stores membership functions of the conclusion portion in order to develop a second bit mapping. Each of the first and second storage areas has X addresses which are designated by an input signal and Y addresses which are designated by a membership value.
    Type: Grant
    Filed: January 3, 1991
    Date of Patent: March 29, 1994
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Takeshi Hamamoto
  • Patent number: 5235199
    Abstract: A semiconductor memory has many memory cells each comprising a transistor and a capacitor. In each memory cell, one of the source and drain regions of the transistor is connected to a bit line. The bit line is formed above the transistor. The capacitor comprises a first capacitor electrode formed on a substrate and a second capacitor electrode formed on an insulation film coated on the surface of the first capacitor electrode. The first capacitor electrode is connected to the other of the source and drain regions of the transistor. The first capacitor electrode is formed above the bit line.To manufacture such a semiconductor memory, each memory cell region is separately formed on the surface of a substrate. A gate insulation film is formed on the memory cell region. A gate electrode is formed on the gate insulation film. The gate electrode is used as a mask to dope the substrate with impurities to form source and drain regions of a transistor.
    Type: Grant
    Filed: February 7, 1992
    Date of Patent: August 10, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takeshi Hamamoto, Fumio Horiguchi, Katsuhiko Hieda
  • Patent number: 5227997
    Abstract: The semiconductor circuit device includes a first column decoder for decoding an internal column address and generating a column select signal which selects one column, and a second column decoder for simultaneously selecting a plurality of successively adjacent columns from a memory cell array in accordance with the column select signal. The second column decoder selects the same column in a duplicated way in response to different column select signals. Since the same column is selected in a duplicate way by the different column select signals, it will be possible to simultaneously select a desired combination of a plurality of columns. A combination of a plurality of columns simultaneously selected can be arbitrarily set and a desired combination of columns can be selected with a simplified circuit structure at high speed.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: July 13, 1993
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigeru Kikuda, Takeshi Hamamoto
  • Patent number: 5146300
    Abstract: A semiconductor integrated circuit device including a semiconductor substrate having a main surface; a first conductive region formed on the main surface; a second conductive region formed on the main surface, spaced apart from the first conductive region and to be electrically connected to the first conductive region; and a capacitor having a storage node connecting the first and second conductive regions. The storage node serves to connect the first and second conductive regions and simultaneously stores charges. In other aspects of the invention, there are provided a memory cell having a structure described above, and a method of manufacturing the above-described semiconductor integrated circuit device.
    Type: Grant
    Filed: February 10, 1992
    Date of Patent: September 8, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takeshi Hamamoto, Toshifumi Kobayashi, Tadato Yamagata, Masaaki Mihara
  • Patent number: 5130945
    Abstract: Each match line is connected to a plurality of CAM cells constituting a CAM array. The respective CAM cells store data applied through a bit line and an inverted-bit line in its data storage portion when selected by a word line. The stored data are applied to a data comparison portion to be compared with retrieval data applied through the bit line and the inverted-bit line, thereby detecting match or mismatch therebetween. A comparison result of the data comparison portion is first stored in a capacitance element in the form of charge. In order to prevent escape of the information stored in the capacitance element, a blocking means blocks a part of a charge and discharge path for the capacitance element. A charge transfer means provided between the capacitance element and the match line transfers a certain amount of charge from either one to the other when information of mismatch is stored in the capacitance element. This causes fluctuation of charge potential on the match line.
    Type: Grant
    Filed: July 12, 1990
    Date of Patent: July 14, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takeshi Hamamoto, Toshifumi Kobayashi, Masaaki Mihara
  • Patent number: 5126968
    Abstract: A semiconductor memory device comprises a plurality or CAM cells. In a refreshing operation, data of "1" is applied to all of bit lines and inversion bit lines. In the CAM cells storing the data "1", writing of the data "1" onto the bit lines and the inversion bit lines is performed. Then, the data of "0" is applied to all of the bit lines and the inversion bit lines. In the CAM cells storing the data "0", writing of the data "0" onto the bit lines and the inversion bit lines is performed. In a partial writing operation, in the CAM cells to which writing is performed, a first control node is activated, thereby making it possible to write the CAM cells. In the rest of the CAM cells, the first control node is inactivated, thereby making it impossible to write the CAM cells.
    Type: Grant
    Filed: October 30, 1990
    Date of Patent: June 30, 1992
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takeshi Hamamoto, Toshifumi Kobayashi, Tadato Yamagata, Masaaki Mihara
  • Patent number: 5106774
    Abstract: A dynamic random access memory is disclosed which includes a trench type memory cell having a transistor formed in a semiconductive substrate, and a capacitor arranged in a trench formed in the substrate and having a trench structure. The capacitor includes an impurity-doped semiconductive layer formed on the substrate so as to surround the trench and having a conductivity type opposite to that of the substrate, a first capacitor electrode formed in the trench, and a second capacitor electrode having a portion insulatively stacked with said first capacitor electrode in the trench.
    Type: Grant
    Filed: February 4, 1991
    Date of Patent: April 21, 1992
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsuhiko Hieda, Fumio Horiguchi, Takeshi Hamamoto, Akihiro Nitayama, Kazumasa Sunouchi, Kei Kurosawa, Fujio Masuoka
  • Patent number: 4965767
    Abstract: A memory cell circuit of an associative memory composed of only four NMOS transistors is disclosed. Each memory cells of the circuit is connected two bit lines, a word line, a match setup line for commanding coincidence detection, and a match line for transferring the results of detection. The data signals are stored in the gate capacity of each of the transistors 3. This simplified memory cell circuit contributes to higher integration of the associative memory.
    Type: Grant
    Filed: July 17, 1989
    Date of Patent: October 23, 1990
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mitsuya Kinoshita, Masaaki Mihara, Toshifumi Kobayashi, Takeshi Hamamoto
  • Patent number: 4910056
    Abstract: A center hub holder tape includes a generally nonstretchable carrier tape having a series of apertures formed therethrough and spaced at an equal interval from one another along the length of the carrier tape. A series of center hubs for use in a recording disc are carried by the carrier tape, with their tubular bodies removably inserted in the apertures in the carrier tape, respectively. An adhesive layer is interposed between one side of the carrier tape and a flange around the body of the center hub to adhesively bond them together. The adhesive layer is releaseably bonded to the one side of the carrier tape so that center hub can be removed from the carrier tape together with the adhesive layer.
    Type: Grant
    Filed: February 1, 1989
    Date of Patent: March 20, 1990
    Assignee: Nitto Denko Corporation
    Inventors: Yasuo Mitoh, Takeshi Hamamoto, Mitsuo Kuramoto