Patents by Inventor Yasuhiko Tsukikawa

Yasuhiko Tsukikawa 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: 11200945
    Abstract: A plurality of memory cells are arranged along a plurality of bit lines and a plurality of word lines. A sense amplifier is connected to each of the bit lines. Arranged along each bit line are at least four memory cells including first to fourth memory cells that are either connected to or disconnected from one of the bit lines by means of first to fourth switching elements according to an active or inactive state of first to fourth word lines. The first memory cell stores a first bit value, the second memory cell stores a second bit value, and the third and fourth memory cells each store a third bit value. A memory cell array control circuit activates and then deactivates the third and fourth word lines, subsequently activates the first and second word lines, and then activates the sense amplifier.
    Type: Grant
    Filed: January 31, 2017
    Date of Patent: December 14, 2021
    Assignee: ZENTEL JAPAN CORPORATION
    Inventors: Takashi Kubo, Masaru Haraguchi, Takeshi Hamamoto, Kenichi Yasuda, Yasuhiko Tsukikawa, Hironori Iga
  • Patent number: 10991418
    Abstract: A control device of the invention for a semiconductor memory device comprising an interface conforming to JEDEC standard of DDRx-SDRAM or LPDDRx-SDRAM, comprises banks, a read/write control circuit, and a transfer control circuit. Each bank comprises subarrays. Each subarray comprises memory cells arranged along bit lines and word lines. The read/write control circuit controls reading of data from and writing of data to the semiconductor memory device. The transfer control circuit controls data transfer inside the semiconductor memory device and sets to enable an additional transfer command not specified in the JEDEC standard and a transfer command for writing data, read from a transfer source memory cell, to a transfer destination memory cell without passing outside the semiconductor memory device by transmitting a first signal value not used in the JEDEC standard to the semiconductor memory device via at least one signal line of the interface.
    Type: Grant
    Filed: March 6, 2017
    Date of Patent: April 27, 2021
    Assignee: ZENTEL JAPAN CORPORATION
    Inventors: Masaru Haraguchi, Takashi Kubo, Yasuhiko Tsukikawa, Hironori Iga, Kenichi Yasuda, Takeshi Hamamoto
  • Publication number: 20200135261
    Abstract: According to a control device of a first aspect of the invention, for a semiconductor memory device comprising an interface conforming to JEDEC (Joint Electron Device Engineering Council) standard of DDRx-SDRAM or LPDDRx-SDRAM, the control device comprises a plurality of banks, a read/write control circuit, and a transfer control circuit. The banks are connected to one another by an internal data bus, and each bank, separated from one another by at least one sense amplifier row comprising a plurality of sense amplifiers, comprises a plurality of subarrays. Each subarray comprises a plurality of memory cells arranged along a plurality of bit lines and a plurality of word lines orthogonal to the bit lines. The read/write control circuit controls reading of data from the semiconductor memory device and writing of data to the semiconductor memory device.
    Type: Application
    Filed: March 6, 2017
    Publication date: April 30, 2020
    Inventors: Masaru Haraguchi, Takashi Kubo, Yasuhiko Tsukikawa, Hironori Iga, Kenichi Yasuda, Takeshi Hamamoto
  • Publication number: 20190378561
    Abstract: A plurality of memory cells are arranged along a plurality of bit lines and a plurality of word lines. A sense amplifier is connected to each of the bit lines. Arranged along each bit line are at least four memory cells including first to fourth memory cells that are either connected to or disconnected from one of the bit lines by means of first to fourth switching elements according to an active or inactive state of first to fourth word lines. The first memory cell stores a first bit value, the second memory cell stores a second bit value, and the third and fourth memory cells each store a third bit value. A memory cell array control circuit activates and then deactivates the third and fourth word lines, subsequently activates the first and second word lines, and then activates the sense amplifier.
    Type: Application
    Filed: January 31, 2017
    Publication date: December 12, 2019
    Inventors: TAKASHI KUBO, MASARU HARAGUCHI, TAKESHI HAMAMOTO, KENICHI YASUDA, YASUHIKO TSUKIKAWA, HIRONORI IGA
  • Patent number: 7288965
    Abstract: A level conversion circuit that converts a signal outputted from a second internal circuit receiving a first power supply voltage to a signal of a level of a second power supply voltage having a voltage level different than the first power supply voltage to apply its output signal to a first internal circuit, is provided with a mechanism for cutting off a path passing a through current in the level conversion circuit when the first power supply voltage is cut off.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: October 30, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Kyoji Yamasaki, Yasuhiko Tsukikawa
  • Publication number: 20070103197
    Abstract: A level conversion circuit that converts a signal outputted from a second internal circuit receiving a first power supply voltage to a signal of a level of a second power supply voltage having a voltage level different than the first power supply voltage to apply its output signal to a first internal circuit, is provided with a mechanism for cutting off a path passing a through current in the level conversion circuit when the first power supply voltage is cut off.
    Type: Application
    Filed: December 21, 2006
    Publication date: May 10, 2007
    Applicant: Renesas Technology Corp.
    Inventors: Kyoji Yamasaki, Yasuhiko Tsukikawa
  • Patent number: 7161387
    Abstract: A level conversion circuit that converts a signal outputted from a second internal circuit receiving a first power supply voltage to a signal of a level of a second power supply voltage having a voltage level different than the first power supply voltage to apply its output signal to a first internal circuit, is provided with a mechanism for cutting off a path passing a through current in the level conversion circuit when the first power supply voltage is cut off.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: January 9, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Kyoji Yamasaki, Yasuhiko Tsukikawa
  • Patent number: 7102935
    Abstract: Independent power supply systems are provided for a peripheral circuit other than a column decoder, an array-relevant circuit, and a column decoder respectively, so that a peripheral power supply voltage, an array power supply voltage, and a column decoder power supply voltage generated independently of each other are supplied to the peripheral circuit, the array-relevant circuit, and the column decoder as an operating power supply voltage, respectively. Preferably, the column decoder power supply voltage during normal operation is set as an intermediate voltage between the peripheral power supply voltage and the array power supply voltage. Thus, an array configuration suitable for driving a transistor with a low voltage in order to achieve lower power consumption can be obtained.
    Type: Grant
    Filed: October 26, 2004
    Date of Patent: September 5, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Takeo Miki, Yasuhiko Tsukikawa, Shinji Tanaka
  • Patent number: 7072204
    Abstract: Each cell unit has a cell plate electrically isolated from the cell plates in the other cell units.
    Type: Grant
    Filed: May 18, 2005
    Date of Patent: July 4, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Yasuhiko Tsukikawa, Takashi Ito
  • Publication number: 20050219893
    Abstract: Each cell unit has a cell plate electrically isolated from the cell plates in the other cell units.
    Type: Application
    Filed: May 18, 2005
    Publication date: October 6, 2005
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Yasuhiko Tsukikawa, Takashi Ito
  • Patent number: 6934204
    Abstract: A P-channel MOS transistor is provided between a terminal and an SVIH detection circuit for performing test mode detection. The P-channel MOS transistor is rendered non-conductive when a potential supplied to the terminal that is used commonly for signal input during the test setting and the normal operation is a power-supply potential EXTVDD or below. The SVIH detection circuit detects that a test mode is to be set when the potential at the terminal becomes higher than a prescribed potential. During the normal operation, the terminal is disconnected from the SVIH detection circuit so that the input capacitance of the terminal can be made to be about the same as that of another input terminal, and a high speed operation becomes possible. Moreover, there is no need to take into account the parasitic capacitance of an interconnection line leading to the SVIH detection circuit.
    Type: Grant
    Filed: May 8, 2002
    Date of Patent: August 23, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Takashi Itou, Yasuhiko Tsukikawa
  • Patent number: 6903961
    Abstract: Each of twin-cell units each formed of two DRAM cells has a cell plate electrically isolated from the cell plates in the other twin-cell units. Thereby, voltages on two storage nodes storing mutually complementary data in the same twin-cell unit change similarly to each other owing to capacitive coupling.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: June 7, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Yasuhiko Tsukikawa, Takashi Ito
  • Publication number: 20050088881
    Abstract: Independent power supply systems are provided for a peripheral circuit other than a column decoder, an array-relevant circuit, and a column decoder respectively, so that a peripheral power supply voltage, an array power supply voltage, and a column decoder power supply voltage generated independently of each other are supplied to the peripheral circuit, the array-relevant circuit, and the column decoder as an operating power supply voltage, respectively. Preferably, the column decoder power supply voltage during normal operation is set as an intermediate voltage between the peripheral power supply voltage and the array power supply voltage. Thus, an array configuration suitable for driving a transistor with a low voltage in order to achieve lower power consumption can be obtained.
    Type: Application
    Filed: October 26, 2004
    Publication date: April 28, 2005
    Inventors: Takeo Miki, Yasuhiko Tsukikawa, Shinji Tanaka
  • Publication number: 20050068062
    Abstract: A level conversion circuit that converts a signal outputted from a second internal circuit receiving a first power supply voltage to a signal of a level of a second power supply voltage having a voltage level different than the first power supply voltage to apply its output signal to a first internal circuit, is provided with a mechanism for cutting off a path passing a through current in the level conversion circuit when the first power supply voltage is cut off.
    Type: Application
    Filed: September 23, 2004
    Publication date: March 31, 2005
    Inventors: Kyoji Yamasaki, Yasuhiko Tsukikawa
  • Patent number: 6867994
    Abstract: A field region forming a transistor is provided in a direction crossing a word line and a bit line. A bit line contact is provided corresponding to each bit line in a row direction. Storage node contacts are provided in alignment corresponding to respective columns in the row direction. The size of a basic cell region for forming a single memory cell can be set to 2·F·3·F. Here, F represents a minimum design size. Accordingly, memory cells in a twin cell mode DRAM storing one bit of data with two memory cells can be reduced in size.
    Type: Grant
    Filed: June 19, 2003
    Date of Patent: March 15, 2005
    Assignee: Renesas Technology Corp.
    Inventor: Yasuhiko Tsukikawa
  • Patent number: 6787859
    Abstract: There is provided a semiconductor memory device including eight memory blocks 20a to 20h, first data bus 22a, and second data bus 22b. The eight memory blocks are arranged at respective eight of the total nine areas 11 to 19 defined in a three rows by three columns matrix except for a center area 19. A first data bus 22a linearly extends between memory blocks in the first and second row of the matrix. A second data bus 22b linearly extends between memory blocks in the second and third row of the matrix. The eight memory blocks includes a first group of the four memory blocks arranged adjacent the first data bus and connected to the first data bus and a second group of the four memory blocks arranged adjacent the second data bus and connected to the second data bus.
    Type: Grant
    Filed: August 20, 2002
    Date of Patent: September 7, 2004
    Assignee: Renesas Technology Corp.
    Inventors: Takashi Itou, Masaki Shimoda, Yasuhiko Tsukikawa
  • Publication number: 20040156255
    Abstract: A field region forming a transistor is provided in a direction crossing a word line and a bit line. A bit line contact is provided corresponding to each bit line in a row direction. Storage node contacts are provided in alignment corresponding to respective columns in the row direction. The size of a basic cell region for forming a single memory cell can be set to 2·F·3·F. Here, F represents a minimum design size. Accordingly, memory cells in a twin cell mode DRAM storing one bit of data with two memory cells can be reduced in size.
    Type: Application
    Filed: June 19, 2003
    Publication date: August 12, 2004
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventor: Yasuhiko Tsukikawa
  • Publication number: 20040141361
    Abstract: Each of twin-cell units each formed of two DRAM cells has a cell plate electrically isolated from the cell plates in the other twin-cell units. Thereby, voltages on two storage nodes storing mutually complementary data in the same twin-cell unit change similarly to each other owing to capacitive coupling.
    Type: Application
    Filed: June 26, 2003
    Publication date: July 22, 2004
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Yasuhiko Tsukikawa, Takashi Ito
  • Patent number: 6735133
    Abstract: In a semiconductor memory circuit including a memory cell array and first and second sense amplifier circuits provided at opposite sides of the memory cell array, respectively and having a plurality of first sense amplifiers and a plurality of second sense amplifiers, respectively, a first bit line and sense amplifier interconnecting circuit, a first bit line equalizing circuit and a first short-circuiting transistor circuit are provided between the memory cell array and the first sense amplifier circuit, while a second bit line and sense amplifier interconnecting circuit, a second bit line equalizing circuit and a second short-circuiting transistor circuit are provided between the memory cell array and the second sense amplifier circuit.
    Type: Grant
    Filed: June 12, 2003
    Date of Patent: May 11, 2004
    Assignee: Renesas Technology Corp.
    Inventor: Yasuhiko Tsukikawa
  • Patent number: 6727738
    Abstract: A delay locked loop (DLL) employs a gray code (an alternate code) counter as a delay register. Preventing a carry from arising at more than one bit can minimize skipping of delay time (discontinuous skipping thereof) if a metastable state should occur.
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: April 27, 2004
    Assignee: Renesas Technology Corp.
    Inventor: Yasuhiko Tsukikawa