Patents by Inventor Yasuo Itoh

Yasuo Itoh 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: 5546351
    Abstract: The time required for the program verify and erase verify operations can be shortened. The change of threshold values of memory cells can be suppressed even if the write and erase operations are executed repetitively. After the program and erase operations, whether the operations were properly executed can be judged simultaneously for all bit lines basing upon a change, after the pre-charge, of the potential at each bit line, without changing the column address. In the data rewrite operation, the rewrite operation is not effected for a memory cell with the data once properly written, by changing the data in the data register.
    Type: Grant
    Filed: October 20, 1994
    Date of Patent: August 13, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoharu Tanaka, Masaki Momodomi, Hideo Kato, Hiroto Nakai, Yoshiyuki Tanaka, Riichiro Shirota, Seiichi Aritome, Yasuo Itoh, Yoshihisa Iwata, Hiroshi Nakamura, Hideko Odaira, Yutaka Okamoto, Masamichi Asano, Kaoru Tokushige
  • Patent number: 5508957
    Abstract: An erasable programmable read-only memory with NAND cell structure includes NAND cell blocks, each of which has a selection transistor connected to the corresponding bit line and a series array of memory cell transistors, and a switching transistor connected between the series array of memory cell transistors and ground. Each cell transistor has a floating gate and a control gate. Word lines are connected to the control gates of the cell transistors. In a data writing mode, a selection transistor of a certain cell block containing a selected cell is rendered conductive, so that this cell block is connected to the corresponding bit line. Under such a condition, a decoder circuit stores a desired data (a logic "one" e.g.
    Type: Grant
    Filed: September 26, 1994
    Date of Patent: April 16, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaki Momodomi, Fujio Masuoka, Yasuo Itoh, Hiroshi Iwahashi, Yoshihisa Iwata, Masahiko Chiba, Satoshi Inoue, Riichiro Shirota, Ryozo Nakayama, Kazunori Ohuchi, Shigeyoshi Watanabe, Ryouhei Kirisawa
  • Patent number: 5452249
    Abstract: A non-volatile semiconductor memory device includes a flip-flop circuit for holding write data in one of first and second states. A bit line is connected to the flip-flop circuit via a switching element, and a transistor changes the bit line. A non-volatile memory cell, connected to the bit line and having a MOS transistor structure, stores data when a threshold thereof is set in one of first and second threshold ranges, wherein at the time of a write mode the threshold of the memory cell is shifted from the first threshold range towards the second threshold range while the flip-flop circuit remains in the first state and the shift of the threshold is not effected while the flip-flop circuit remains in the second state, and at the time of a verify mode following the write mode the bit line is kept at a charge potential by the charging transistor while the threshold remains in the second threshold range.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: September 19, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Junichi Miyamoto, Yasuo Itoh, Yoshihisa Iwata
  • Patent number: 5440509
    Abstract: An erasable programmable read-only memory (EPROM) with a NAND cell structure includes NAND cell blocks, each of which has a selection transistor connected to the corresponding bit line and memory cell transistors connected in series. Word lines are connected to control gates of the cell transistors. In a data write mode, a selection transistor of a certain cell block containing a selected cell is rendered conductive to connect the cell block to the corresponding bit line.
    Type: Grant
    Filed: February 24, 1993
    Date of Patent: August 8, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaki Momodomi, Koichi Toita, Yasuo Itoh, Yoshihisa Iwata, Fujio Masuoka, Masahiko Chiba, Tetsuo Endo, Riichiro Shirota, Ryouhei Kirisawa
  • Patent number: 5426516
    Abstract: Color image processing apparatus for displaying color images comprised of terminals for receiving pixel data and control data, first and second frame memories for storing the pixel data of 2 picture frames of image to be displayed, and first and second color look-up tables provided correspondingly with the first and second frame memories for storing color data to be referred by the pixel data in the first and second frame memories, which color data are determined individually between the first and second color look-up tables.
    Type: Grant
    Filed: August 17, 1994
    Date of Patent: June 20, 1995
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Tsuneo Furuki, Yasuo Itoh, Akiyoshi Hamanaka, Kyojiro Sei, Kazuo Hikawa
  • Patent number: 5400279
    Abstract: An electrically erasable programmable read-only memory has an array of programmable memory cells connected to parallel bit lines on a semiconductive substrate. The memory cells include NAND cell blocks each of which has a first selection transistor coupled to a corresponding bit line, a second selection transistor coupled to the ground potential, and a series array of memory cell transistors each having a floating gate and a control gate. Word lines are respectively connected to the control gates of the memory cell transistors. In a data read mode, a selection transistor of a certain NAND cell block including a selected memory cell transistor is rendered conductive to connect this cell block to a bit line associated therewith.
    Type: Grant
    Filed: May 26, 1993
    Date of Patent: March 21, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaki Momodomi, Yasuo Itoh, Yoshihisa Iwata, Fujio Masuoka, Masahiko Chiba
  • Patent number: 5388084
    Abstract: Disclosed is a semiconductor integrated circuit device, which comprises a booster circuit for boosting a source voltage, a voltage limiter having one end connected to the output terminal of the booster circuit, for limiting the output voltage of the booster circuit to a given value, and a voltage setting circuit, connected to the other end of the voltage limiter, for arbitrarily adjusting a voltage at the other end of the voltage limiter. This design can keep the output voltage of the booster circuit at a constant level and can set that output voltage to an arbitrary voltage.
    Type: Grant
    Filed: September 29, 1993
    Date of Patent: February 7, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuo Itoh, Sumio Tanaka, Junichi Miyamoto, Hiroshi Nakamura, Yoshihisa Iwata, Kenichi Imamiya, Yoshihisa Sugiura
  • Patent number: 5368088
    Abstract: Molten metal is supplied to a pouring basin formed between cooling members, such as movable cooling drums. A closed space is formed at a meniscus area whereat any one of the cooling members starts to come into contact with the molten metal, and a soluble gas or a mixture of soluble and insoluble gases is supplied to and filled in the closed space, thereby covering the meniscus area with the gas or the mixture. This arrangement enables a continuous casting of a thin metal sheet without surface cracks and having excellent surface characteristics.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: November 29, 1994
    Assignees: Nippon Steel Corporation, Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Takashi Furuya, Hidemaro Takeuchi, Akio Kasama, Yasuo Itoh, Motoya Fujii, Hideki Oka, Shogo Matsumura, Kunimasa Sasaki, Keiichi Yamamoto
  • Patent number: 5361227
    Abstract: The time required for the program verify and erase verify operations can be shortened. The change of threshold values of memory cells can be suppressed even if the write and erase operations are executed repetitively. After the program and erase operations, whether the operations were properly executed can be judged simultaneously for all bit lines basing upon a change, after the pre-charge, of the potential at each bit line, without changing the column address. In the data rewrite operation, the rewrite operation is not effected for a memory cell with the data once properly written, by changing the data in the data register.
    Type: Grant
    Filed: December 18, 1992
    Date of Patent: November 1, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoharu Tanaka, Masaki Momodomi, Hideo Kato, Hiroto Nakai, Yoshiyuki Tanaka, Riichiro Shirota, Seiichi Aritome, Yasuo Itoh, Yoshihisa Iwata, Hiroshi Nakamura, Hideko Odaira, Yutaka Okamoto, Masamichi Asano, Kaoru Tokushige
  • Patent number: 5327395
    Abstract: A NOR operation is performed on the address bit by bit by a NOR circuit, and when the final address in a page is detected from the result of the NOR operation by a final address detection circuit, a program starting circuit executes data writing to a memory cell. This can ensure detection of the final address in a page without using a counter circuit. It is therefore possible to simplify the structure of the final address detection circuit and reduce the circuit area occupying in a semiconductor memory device.
    Type: Grant
    Filed: October 6, 1992
    Date of Patent: July 5, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihisa Sugiura, Yoshihisa Iwata, Masaki Momodomi, Yasuo Itoh, Tomoharu Tanaka, Yoshiyuki Tanaka
  • Patent number: 5278794
    Abstract: A NAND-cell type electrically erasable and programmable read only memory includes an array of rows and columns of memory cells associated with parallel bit lines on a semiconductive substrate. Each memory cell essentially consists of a floating-gate field effect transistor having a floating gate and an insulated control gate. The memory cell array is divided into a plurality of cell blocks, each of which includes NAND cell sections each including a predetermined number of a series-connected memory cell transistors. A redundancy cell section is provided which includes an array of redundancy memory cells containing at least one spare cell block. A row redundancy circuit is connected to a row decoder, and is responsive to an address buffer. The redundancy circuit replaces a defective block containing a defective memory cell or cells with the spare cell block.
    Type: Grant
    Filed: October 14, 1992
    Date of Patent: January 11, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiyuki Tanaka, Yasuo Itoh, Masaki Momodomi, Yoshihisa Iwata, Tomoharu Tanaka
  • Patent number: 5268867
    Abstract: The present invention provides a semiconductor memory device capable of reducing its current consumption, controlling the generation of noise, and increasing in access using a precharge voltage applied to a precharge circuit. In the semiconductor memory device, a precharge circuit is connected to a pair of data input/output lines, and includes a MOS transistor connected between one of the data input/output lines and a node of a precharge voltage and a MOS transistor connected between the other data input/output line and a node of the precharge voltage. The gates of the MOS transistors are supplied with control signals so that the MOS transistors are turned on when the data input/output lines are precharged. A MOS transistor is connected to the data input/output lines for equalizing them. The precharge voltage is set to half of a value obtained by subtracting the threshold voltage of the MOS transistor from the power supply voltage.
    Type: Grant
    Filed: October 6, 1992
    Date of Patent: December 7, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaki Momodomi, Yasuo Itoh, Yoshihisa Iwata, Tomoharu Tanaka, Yoshiyuki Tanaka
  • Patent number: 5247480
    Abstract: An electrically erasable programmable read-only memory has memory cell blocks, each of which has NAND type cell units associated with the bit lines respectively. Each cell unit has a series-circuit of floating gate type memory cell transistors and a selection transistor provided between the corresponding bit line and the series-circuit of memory cell transistors. A row decoder is provided in common to the memory cell blocks, for generating an "H" level voltage which is supplied to a selection gate control line connected to the selection transistor and to a selected word line or lines in a cell unit. A voltage boost circuit is provided for every memory cell block, for causing the "H" level voltage to increase up to a preselected potential level which is high enough to render the cell transistors conductive. The voltage boost circuit includes a first booster section for the selection gate control line, and a second section for the word lines.
    Type: Grant
    Filed: October 9, 1991
    Date of Patent: September 21, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuo Itoh, Masaki Momodomi, Yoshihisa Iwata, Tomoharu Tanaka, Fujio Masuoka
  • Patent number: 5179427
    Abstract: A NAND cell type EEPROM has parallel data transmission lines formed above a substrate, and a memory cell section including a plurality of NAND type cell units containing a NAND type cell unit that is associated with a certain bit line of the bit lines. This NAND type cell unit has a series-circuit of a preselected number of data storage transistors with control gates, and a selection transistor. A substrate voltage-stabilizing layer is insulatively provided above the substrate and positioned in the field area in adjacent to the certain bit line. The conductive layer is connected to the substrate by a contact portion so that the substrate voltage can be constantly set to a preselected voltage potential of a fixed value during the NAND type cell unit is being subjected to the write and erase modes.
    Type: Grant
    Filed: April 15, 1992
    Date of Patent: January 12, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryozo Nakayama, Riichiro Shirota, Yasuo Itoh, Ryouhei Kirisawa, Hideko Odaira, Masaki Momodomi, Yoshihisa Iwata, Tomoharu Tanaka, Seiichi Aritome, Tetsuo Endoh, Fujio Masuoka
  • Patent number: 5103895
    Abstract: Molten metal is supplied to a pouring basin formed between cooling members, such as movable cooling drums. A closed space is formed at a meniscus area whereat any one of the cooling members starts to come into contact with the molten metal, and a soluble gas or a mixture of soluble and insoluble gases is supplied to and filled in the closed space, thereby covering the meniscus area with the gas or the mixture. This arrangement enables a continuous casting of a thin metal sheet without surface cracks and having excellent surface characteristics.
    Type: Grant
    Filed: July 17, 1990
    Date of Patent: April 14, 1992
    Assignees: Nippon Steel Corporation, Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Takashi Furuya, Hidemaro Takeuchi, Akio Kasama, Yasuo Itoh, Motoya Fujii, Hideki Oka, Shogo Matsumura, Kunimasa Sasaki, Keiichi Yamamoto
  • Patent number: 5075890
    Abstract: An electrically erasable programmable read-only memory has memory cell blocks, each of which has NAND type cell units associated with the bit lines respectively. Each cell unit has a series-circuit of floating gate type memory cell transistors and a selection transistor provided between the corresponding bit line and the series-circuit of memory cell transistors. A row decoder is provided in common to the memory cell blocks, for generating an "H" level voltage which is supplied to a selection gate control line connected to the selection transistor and to a selected word line or lines in a cell unit. A voltage boost circuit is provided for every memory cell block, for causing the "H" level voltage to increase up to a preselected potential level which is high enough to render the cell transistors conductive. The voltage boost circuit includes a first booster section for the selection gate control line, and a second section for the word lines.
    Type: Grant
    Filed: April 30, 1990
    Date of Patent: December 24, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuo Itoh, Masaki Momodomi, Yoshihisa Iwata, Tomoharu Tanaka, Fujio Masuoka
  • Patent number: 5050125
    Abstract: An erasable programmable read-only memory with a NAND cell structure including NAND cell blocks, each of which has a selection transistor connected to the corresponding bit line and memory cell transistors connected is series. Word lines are connected to control gates of the cell transistors. In a data write mode, a selection transistor of a certain cell block containing a selected cell is rendered conductive to connect the cell block to the corresponding bit line.
    Type: Grant
    Filed: November 17, 1988
    Date of Patent: September 17, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaki Momodomi, Koichi Toita, Yasuo Itoh, Yoshihisa Iwata, Fujio Masuoka, Masahiko Chiba, Tetsuo Endo, Riichiro Shirota, Ryouhei Kirisawa
  • Patent number: 5043942
    Abstract: A NAND cell type EEPROM has a substrate, parallel bit lines formed above the substrate, and a memory cell section including an array of NAND type cell units associated with the same corresponding bit line. Each of the NAND type cell units has a series-circuit of eight data storage transistors and at least one selection transistor. Each data storage transistor has a floating gate for storing carriers injected thereinto by tunneling and a control gate respectively connected to word lines. A control gate driver circuit is provided in common for all the NAND type cell units that are assisted with the same bit line. Transfer gates are connected between the common driver circuit and the NAND cell units.
    Type: Grant
    Filed: June 4, 1990
    Date of Patent: August 27, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihisa Iwata, Masaki Momodomi, Yasuo Itoh, Tomoharu Tanaka, Hideko Odaira
  • Patent number: 4983633
    Abstract: Amide-compounds represented by the formula (I): ##STR1## wherein R.sub.1 represents hydrogen, lower alkoxy, hydroxy, lower alkyl, halogen, amino which can be substituted by lower alkyl, nitro, cyano, sulfamoyl which can be substituted by lower alkyl, R.sub.2 represents hydrogen, lower alkoxy, hydroxy, lower alkyl, halogen, amino, nitro, wherein R.sub.1 and R.sub.2 can be combined to form methylenedioxy, R.sub.3 means hydrogen, lower alkyl, halogen, or amino, R.sub.4 and R.sub.5 may be the same or different and each represents lower alkyl or wherein R.sub.4 and R.sub.
    Type: Grant
    Filed: September 2, 1988
    Date of Patent: January 8, 1991
    Assignee: Hokuriku Pharmaceutical Co., Ltd.
    Inventors: Yasuo Itoh, Hideo Kato, Eiichi Koshinaka, Nobuo Ogawa, Hiroyuki Nishino, Jun Sakaguchi
  • Patent number: 4971990
    Abstract: Phenoxyethylamine derivatives represented by the general formula (I): ##STR1## wherein R.sub.1 and R.sub.5 represent lower-alkyl, R.sub.2 and R.sub.3, which may be the same or different, each represents hydrogen or lower-alkyl, or ##STR2## represents a 5- or 6-membered ring system which may include nitrogen, oxygen or sulfur as a ring membered atom, R.sub.4 represents hydrogen or lower-alkyl, and n represents an integer selected from 1 to 3, their optical isomers and pharmacologically-acceptable acid addition salts, which exhibit excellent .alpha..sub.1 -blocking activity, a process for their preparation, pharmaceutical compositions thereof, and a method for the treatment of a subject afflicted with hypertension or dysuria by administrating such a compound, are all disclosed.
    Type: Grant
    Filed: January 24, 1989
    Date of Patent: November 20, 1990
    Assignee: Hokuriku Pharmaceutical Co., Ltd.
    Inventors: Yasuo Itoh, Hideo Kato, Eiichi Koshinaka, Nobuo Ogawa, Kazuya Mitani, Shunichiro Sakurai