Patents by Inventor Koichiro Mashiko

Koichiro Mashiko 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: 4817056
    Abstract: In a semiconductor memory device of a redundancy configuration having lines (rows or columns) of main memory cells and a line of spare memory cells made to substitute a defective line responsive to the address of the defective line, a comparator compares an address input to the memory device, with the address of the defective line which has been programmed in it, and a spare line selector selects the spare line when the input address is found to coincide with the programmed address. The comparator comprises a dynamic NOR gate having discharge paths each formed of a gate element receiving a bit or its inversion of the input address to be opened or closed depending on the value of the particular bit of the input address currently applied, and a PROM element in series with the gate element. The dynamic NOR gate has a first node forming an output thereof and a second node, each of the series connections of the PROM element and the gate element is connected across the first and the second nodes.
    Type: Grant
    Filed: July 24, 1987
    Date of Patent: March 28, 1989
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kiyohiro Furutani, Koichiro Mashiko, Kazutami Arimoto, Noriaki Matsumoto, Yoshio Matsuda
  • Patent number: 4797001
    Abstract: The invention relates to a substrate bias generator for use in dynamic random access memory, and in which either a plurality of transistors for rectification are disposed between a coupling capacitor and a substrate potential electrode or a threshold voltage of a transistor for rectification between the coupling capacitor and the substrate potential electrode is different from a threshold voltage of the other transistor making the absolute value of substrate potential smaller thereby, so that a depletion-layer distance formed between a P-type substrate and N.sup.+ -type substrate is shortened and that effect due to incidence of .alpha.-particle is reduced resulting in reducing soft error rate.
    Type: Grant
    Filed: July 29, 1987
    Date of Patent: January 10, 1989
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Noriaki Matsumoto, Koichiro Mashiko, Kazutami Arimoto, Kiyohiro Furutani, Yoshio Matsuda
  • Patent number: 4788457
    Abstract: A CMOS row decoder circuit in which a row decoder for selecting a single word line from a memory cell array and a column decoder for selecting a single bit line can use in common an internal address signal transmission line.
    Type: Grant
    Filed: September 9, 1987
    Date of Patent: November 29, 1988
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Koichiro Mashiko, Kazutami Arimoto, Kiyohiro Furutani, Noriaki Matsumoto, Yoshio Matsuda
  • Patent number: 4734889
    Abstract: A spare Y decoder is provided with MOS transistors 14 and 20 for charge on both sides of a parasitic resistor 19. As a result, nodes N1 and N2 are rapidly charged by the MOS transistors 20 and 14 for charge, respectively.
    Type: Grant
    Filed: March 6, 1986
    Date of Patent: March 29, 1988
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Koichiro Mashiko, Yoshikazu Morooka, Tadato Yamagata, Yuto Ikeda
  • Patent number: 4710789
    Abstract: In a semiconductor memory device, memory cells of a first column each comprising an N-channel FET are connected to a first bit line, and memory cells of a second column each comprising a P-channel FET are connected to a second bit line. The first bit line and the second bit line are connected to complementary terminals of a sense amplifier to form a folded-bit line pair. A work line is connected to the gate of the N-channel FET of one of the memory cells of the first column and to the gate of the P-channel FET of one of the memory cells of the second column. The word line is selectively provided with a first voltage to make conductive the N-channel FET connected thereto and to make nonconductive the P-channel FET connected thereto, or a second voltage to make conductive the P-channel FET connected thereto and to make nonconductive the N-channel FET connected thereto, or a third voltage to make nonconducitve both the N-channel FET and the P-channel FET connected thereto.
    Type: Grant
    Filed: December 3, 1986
    Date of Patent: December 1, 1987
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kiyohiro Furutani, Koichiro Mashiko, Kazutami Arimoto
  • Patent number: 4689770
    Abstract: An LSI semiconductor memory device in which errors in reading out memory cells connected to outermost bit lines of a memory cell array of the device are substantially eliminated. In accordance with the invention, this is done by making capacitances associated with the bit lines of respective ones of the memory cell array substantially equal to one another. To accomplish this, the configuration of an inside portion of wiring other than the bit lines of the array is made the same as that of the bit lines, and the distance between the outermost bit line and the other wiring is made equal to the distance between adjacent ones of the bit lines.
    Type: Grant
    Filed: October 28, 1985
    Date of Patent: August 25, 1987
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroshi Miyamoto, Koichiro Mashiko, Toshifumi Kobayashi, Michihiro Yamada
  • Patent number: 4641281
    Abstract: A dynamic random access memory that contains a memory cell array including a plurality of memory cells includes a pre-amplifier intended to amplify data which is read out from a memory cell accessed by an address signal; a main-amplifier intended to amplify the output of the pre-amplifier and output the amplified signal; and a driver circuit intended to output a driving signal for driving the main-amplifier, the driver circuit includes a first and a second transistor, wherein a drain of the first transistor is connected to a node corresponding to an output terminal of the driver circuit, with a source of the first transistor being earthed and with a gate thereof being connected to the drain of the second transistor, and wherein a gate of the second transistor is connected to the node with a source thereof being earthed.
    Type: Grant
    Filed: August 8, 1984
    Date of Patent: February 3, 1987
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Koichiro Mashiko, Michihiro Yamada, Kazutami Arimoto, Hiroshi Miyamoto, Toshifumi Kobayashi, Yoshikazu Morooka
  • Patent number: 4520466
    Abstract: A dynamic random access memory comprises a one-transistor type MOS dynamic random access memory of an open bit line type, which comprises two memory arrays at the left and the right sides of sense amplifying circuits (2). Each of both memory arrays comprises a plurality of memory cells (1) and dummy cells (3), each of columns of memory cells (1) and dummy cells (3) having a cell plate voltage control circuit (13) connected at the end thereof through a cell plate (8). Each cell plate voltage control circuit (13) is provided with a control signal .phi..sub.G having a level changing during a period when any of word lines (5) or dummy word lines (6) is selected and is responsive to selection of the word line (5) or the dummy word line (6) to discharge the voltage of the cell plate (8) and is responsive to a change of the level of the control signal .phi..sub.G to charge the cell plate (8).
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: May 28, 1985
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Koichiro Mashiko
  • Patent number: 4333168
    Abstract: A plurality of single transistor memory cells with electrically charged capacitors and two similar dummy memory cells are electrically coupled in symmetric relationship to a sense amplifier for each row of the disclosed memory circuit. An address signal selects a word line connected to the memory cell on one side of the amplifier and a dummy word line connected to the dummy memory cell on its other side and applies a word signal to the selected word lines, in order to read out electric charges on the capacitors, and the amplifier amplifies a potential difference due to the read charges. For each row two dummy word lines are connected to delay means coupled to the amplifier to form an activating signal for the amplifier by delaying a potential rise developed on the selected dummy word line.
    Type: Grant
    Filed: August 8, 1980
    Date of Patent: June 1, 1982
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Koichiro Mashiko, Toshio Ichiyama, Makoto Taniguchi