Patents by Inventor Ryo Fukuda

Ryo Fukuda 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: 8072830
    Abstract: A semiconductor integrated circuit device includes a plurality of memory macros, macro-common register block, and memory macro operation setting circuits. The macro-common register block has macro-common registers which are provided outside the plurality of memory macros and supply memory macro operation specifying signals to the plurality of memory macros. The memory macro operation setting circuits are respectively provided in the plurality of memory macros and are each configured to set an operating state of the memory macro in response to the memory macro operation specifying signal supplied from the macro-common register.
    Type: Grant
    Filed: May 7, 2009
    Date of Patent: December 6, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Ryo Fukuda
  • Patent number: 8036021
    Abstract: A memory cell array includes a plurality of memory cells arranged at intersections of bit line pairs and word lines. Each memory cell includes a first transistor having one main electrode connected to a first bit line, a second transistor having one main electrode connected to a second bit line, a first node electrode for data-storage connected to the other main electrode of the first transistor, a second node electrode for data-storage connected to the other main electrode of the second transistor, and a shield electrode formed surrounding the first and second node electrodes. The first and second transistors have respective gates both connected to an identical word line, and the first and second bit lines are connected to an identical sense amp. The first and second node electrodes, the first and second bit lines, the word line and the shield electrode are isolated from each other using insulating films.
    Type: Grant
    Filed: November 18, 2009
    Date of Patent: October 11, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryo Fukuda, Daisaburo Takashima
  • Patent number: 8027216
    Abstract: A memory may includes: word lines; bit lines; memory array blocks including memory cells, each memory array block being a unit of a data read operation or a data write operation; a row decoder configured to selectively drive the word lines; sense amplifiers configured to detect data; and an access counter provided for each memory cell block, the access counter counting the number of times of accessing the memory array blocks in order to read data or write data, and activating a refresh request signal when the number of times of access reaches a predetermined number of times, wherein during an activation period of the refresh request signal of the access counter, the row decoder periodically and sequentially activates the word lines of the memory array blocks corresponding to the access counter, and the sense amplifier performs a refresh operation of the memory cells connected to the activated word lines.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: September 27, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryo Fukuda, Yohji Watanabe
  • Patent number: 7995369
    Abstract: This disclosure concerns a semiconductor memory device including bit lines; word lines; semiconductor layers arranged to correspond to crosspoints of the bit lines and the word lines; bit line contacts connecting between a first surface region and the bit lines, the first surface region being a part of a surface region of the semiconductor layers directed to the word lines and the bit lines; and a word-line insulating film formed on a second surface region adjacent to the first surface region, the second surface region being a part of out of the surface region, the word-line insulating film electrically insulating the semiconductor layer and the word line, wherein the semiconductor layer, the word line and the word-line insulating film form a capacitor, and when a potential difference is given between the word line and the bit line, the word-line insulating film is broken in order to store data.
    Type: Grant
    Filed: December 11, 2008
    Date of Patent: August 9, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiro Minami, Ryo Fukuda, Takeshi Hamamoto
  • Publication number: 20110148211
    Abstract: In a semiconductor device according to the embodiment, a core circuit is an IC. A peripheral circuit includes a driver supplied with voltages from an internal power source and an external power source and outputting data transferred from the core circuit, and a fetch portion transferring the digital data to the driver. A first power source supplies an internal voltage to the driver via a power source line. A second power source includes current driving strings each including a current driving element and a switching element connected in series between the external power source and the power source line. The second power source supplies a current to the power source line separately from the first power source line by driving the current driving strings. A power source controller controls the second power source to drive the current driving strings when a logic transition occurs among consecutive bits of the data.
    Type: Application
    Filed: September 20, 2010
    Publication date: June 23, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Fumiyoshi MATSUOKA, Ryo Fukuda
  • Publication number: 20110133791
    Abstract: An output buffer circuit in accordance with an embodiment comprises a plurality of buffer circuits, each of the buffer circuits including a transistor operative to change an output signal of an output terminal in response to a change in an input signal, the output buffer circuit being configured to enable the plurality of buffer circuits to be driven selectively. Each of the plurality of buffer circuits includes a plurality of output transistors having respective current paths formed in parallel to one another between a fixed voltage terminal supplying a certain fixed voltage and an output terminal, and being selectively rendered in an operable state in accordance with a control signal provided from external. The plurality of output transistors included in each of the plurality of buffer circuits are formed having a certain size ratio.
    Type: Application
    Filed: December 8, 2010
    Publication date: June 9, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masaru Koyanagi, Yasufumi Kajiyama, Ryo Fukuda, Fumiyoshi Matsuoka, Yasuhiro Suematsu
  • Patent number: 7958279
    Abstract: A semiconductor integrated circuit apparatus, comprising a data transmitter circuit, and a plurality of data receiver circuits each having a data converter circuit which restores each of bits of identification number data and transfer data from a shift register of the data transmitter circuit to 2-bit complementary data transmitted via first and second transmission lines, a reception control circuit which, when a transfer completion signal has been received via a third transmission line, compares an allocated identification number with the restored identification number data, and a shift register provided in association with the reception control circuit, wherein each reception control circuit feeds transfer data transmitted from the data transmitter circuit corresponding to the identification number data to the associated shift register in accordance with a result of comparison between the identification number data and the allocated identification number.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: June 7, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomohisa Takai, Ryo Fukuda
  • Publication number: 20110128073
    Abstract: According to one embodiment, a semiconductor integrated circuit includes first to six transistors and a constant current source circuit. The first and second transistors form a current mirror circuit connected to a first power source node. The third and fourth transistors form a differential pair circuit. The third and fourth transistors receive first and second external signals at their gates, respectively. The constant current source circuit has one end connected to source terminals of the third and fourth transistors, and the other end connected to a second power source node. The fifth and sixth transistors form a current pathway between a common gate node of the first and second transistors and the constant current source circuit. The gate of fifth transistor is connected to a signal output node. The gate of sixth transistor receives a signal of logic opposite to a signal to be obtained at the signal output node.
    Type: Application
    Filed: September 17, 2010
    Publication date: June 2, 2011
    Inventors: Ryo FUKUDA, Masaru KOYANAGI
  • Publication number: 20110128063
    Abstract: According to one embodiment, a semiconductor integrated circuit includes first and second level shift circuits. The first level shifter includes a plurality of transistors and is connected to a power source voltage supply node of a first power source system and to which a first signal of a second power source system and a level inversion signal of the first signal are input. The second level shifter includes a plurality of transistors and is connected to the power source voltage supply node of the first power source system and to which the level inversion signal of the first signal of the second power source system and an output signal of the first level shifter are input. The first and second level shifters have substantially the same circuit configuration and driving abilities of corresponding ones of the transistors in the first and second level shifters are substantially set equal.
    Type: Application
    Filed: September 17, 2010
    Publication date: June 2, 2011
    Inventors: Ryo Fukuda, Masaru Koyanagi
  • Patent number: 7893478
    Abstract: This disclosure concerns a semiconductor storage device comprising a semiconductor layer provided on the insulation layer provided on the semiconductor substrate; a source layer and a drain layer provided in the semiconductor layer; a body provided between the source layer and the drain layer, the body being in an electrically floating state; an emitter layer contacting with the source layer, the emitter layer having an opposite conductive type to the source layer; a word line including the source layer, the drain layer, and the body, the word line being provided to memory cells arrayed in a first direction in a plurality of tow-dimensionally arranged memory cells; a source line connected to the source layers of the memory cells arrayed in the first direction; and a bit line connected to the drain layers of the memory cells arrayed in a second direction intersecting the first direction.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: February 22, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoki Higashi, Takashi Ohsawa, Ryo Fukuda
  • Patent number: 7888769
    Abstract: A semiconductor integrated circuit device according to an embodiment of the present invention includes: a semiconductor substrate; an internal circuit formed on the semiconductor substrate, a first potential and a second potential being supplied to the internal circuit, thereby applying an operating voltage to the internal circuit; a fuse disposed above a semiconductor region of a first conductivity type, and electrically connected to the internal circuit, the semiconductor region being supplied with the second potential and being formed in the semiconductor substrate; and a protective element formed in the semiconductor region of the first conductivity type and protecting the internal circuit in response to positive and negative abnormal voltages generated in a wiring through which the fuse and the internal circuit are connected to each other.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: February 15, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaki Kondo, Ryo Fukuda, Yohji Watanabe, Mitsutoshi Nakamura
  • Patent number: 7859897
    Abstract: A memory includes: memory cells including floating bodies, wherein in a data holding state, a potential of the first gate electrode is set to be higher than one of potentials of the source and drain layer and lower than the other of the potentials of the source and drain layer so that electric charges flow in the body region, and a potential of the second gate electrode is set to be higher as an absolute value than those of potentials of the source layer, drain layer, and first gate electrode so that electric charges flow from the body region, and in the data holding state, the memory cell is kept in a stationary state that a first amount of the electric charges flowing in the body region per unit time is substantially the same as a second amount of the electric charges flowing from the body region per unit time.
    Type: Grant
    Filed: March 11, 2009
    Date of Patent: December 28, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Ryo Fukuda
  • Patent number: 7855917
    Abstract: The disclosure concerns a memory including a floating body provided in a semiconductor layer between a source and a drain and storing data; a first gate dielectric provided on a first surface of the body; a first gate electrode provided on the first surface via the first gate dielectric; a second gate dielectric provided on a second surface of the body different from the first surface; a second gate electrode provided on the second surface via the second gate dielectric; a driver driving the first gate electrode and the second gate electrode; and a sense amplifier writing into the memory cells first data showing a sate of a small charge amount in a state that a voltage of the second gate electrode at a data writing time is brought closer to a potential of the source layer than a voltage of the second gate electrode at a data holding time.
    Type: Grant
    Filed: October 2, 2008
    Date of Patent: December 21, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Ryo Fukuda
  • Patent number: 7852696
    Abstract: This disclosure concerns a memory including a memory cell including a drain, a source and a floating body, wherein when a refresh operation is executed, a first current is carried from the drain or the source to the body and a second current is carried from the body to the second gate electrode by applying a first voltage and a second voltage to the first gate electrode and the second gate electrode, the first voltage and the second voltage being opposite in polarity to each other, and a state of the memory cell is covered to an stationary state in which an amount of the electric charges based on the first current flowing in one cycle of the refresh operation is almost equal to an amount of the electric charges based on the second current flowing in one cycle of the refresh operation.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: December 14, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Ohsawa, Ryo Fukuda
  • Publication number: 20100213991
    Abstract: A delay-locked loop circuit has an adjustment period setting module configured to set a rough adjustment period and a fine adjustment period, a delay time adjustment module configured to increase or decrease a delay stage by a first unit or by a second unit based on a delay stages setting value to generate a second signal by delaying a first signal, a delay module configured to generate a third signal by delaying the second signal by a predetermined time, a phase comparator configured to detect a phase difference between the first signal and the third signal, and a delay controller configured to generate the delay stages setting value based on the phase difference in order to increase or decrease the number of delay stages by the first unit when the rough adjustment period is set and to increase or decrease the number of delay stages by the second unit when the fine adjustment period is set.
    Type: Application
    Filed: February 26, 2010
    Publication date: August 26, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Ryo FUKUDA
  • Publication number: 20100177573
    Abstract: A memory includes a latch circuit latching data from a first and a second bit lines to a first and a second sense nodes; a first data line reading-out the data from the first sense node to an outside; a second data line reading-out the data from the second sense node to the outside; a first write transistor connected between the first bit line and the first or second data line without via the first and second sense node; and a second write transistor connected between the second bit line and the first or second data line without via the first and second sense node, wherein in a write operation, the first write transistor transmits the data from the first or second data line to the first bit line, or the second write transistor transmits the data from the first or second data line to the second bit line.
    Type: Application
    Filed: January 8, 2010
    Publication date: July 15, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Fumiyoshi MATSUOKA, Katsuyuki FUJITA, Ryo FUKUDA, Takashi OHSAWA
  • Patent number: 7732840
    Abstract: A second-conductivity-type transistor includes a source and drain formed by a second-conductivity-type diffusion layer formed on a first-conductivity-type semiconductor layer; and a gate formed on the first-conductivity-type semiconductor layer sandwiched between the second-conductivity-type diffusion layer through an insulating film A first-conductivity-type transistor includes a source and drain formed by a first-conductivity-type diffusion layer formed on a second-conductivity-type semiconductor layer; and a gate formed on the second-conductivity-type semiconductor layer sandwiched between the first-conductivity-type diffusion layer through an insulating film. The second-conductivity-type diffusion layer for configuring the second-conductivity-type transistor is divided into a plurality of regions, each of which being separated by a device isolation region formed on the first-conductivity-type semiconductor layer.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: June 8, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Fumiyoshi Matsuoka, Yohji Watanabe, Ryo Fukuda
  • Patent number: 7710812
    Abstract: A semiconductor memory device includes memory cells; word lines connected to gates of the cells; n bit lines connected to the memory cells; sense amplifiers connected to the bit lines; refresh cells provided to correspond to the word lines, respectively, and provided to correspond to k bit lines, where k is a natural number smaller than n, one of the refresh cells storing therein refresh data indicating whether to perform a refresh operation on k memory cells out of the plural memory cells connected to a corresponding word line out of the plural word lines and connected to the k bit lines, respectively; a refresh sense amplifier reading the refresh data; and a refresh selection part provided to correspond to the refresh sense amplifier, and selecting whether to perform the refresh operation on the k memory cells according to the refresh data read by the refresh sense amplifier.
    Type: Grant
    Filed: June 11, 2008
    Date of Patent: May 4, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Ryo Fukuda
  • Patent number: 7697318
    Abstract: A memory cell array includes a plurality of memory cells arranged at intersections of bit line pairs and word lines. Each memory cell includes a first transistor having one main electrode connected to a first bit line, a second transistor having one main electrode connected to a second bit line, a first node electrode for data-storage connected to the other main electrode of the first transistor, a second node electrode for data-storage connected to the other main electrode of the second transistor, and a shield electrode formed surrounding the first and second node electrodes. The first and second transistors have respective gates both connected to an identical word line, and the first and second bit lines are connected to an identical sense amp. The first and second node electrodes, the first and second bit lines, the word line and the shield electrode are isolated from each other using insulating films.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: April 13, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryo Fukuda, Daisaburo Takashima
  • Patent number: 7692963
    Abstract: The disclosure concerns a semiconductor memory device comprising a semiconductor layer; a charge trap film in contact with a first surface of the semiconductor layer; a gate insulating film in contact with a second surface of the semiconductor layer, the second surface being opposite to the first surface; a back gate electrode in contact with the charge trap film; a gate electrode in contact with the gate insulating film; a source and a drain formed in the semiconductor layer; and a body region provided between the drain and the source, the body region being in an electrically floating state, wherein a threshold voltage or a drain current of a memory cell including the source, the drain, and the gate electrode is adjusted by changing number of majority carriers accumulated in the body region and a quantity of charges trapped into the charge trap film.
    Type: Grant
    Filed: November 2, 2007
    Date of Patent: April 6, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoaki Shino, Akihiro Nitayama, Takeshi Hamamoto, Hideaki Aochi, Takashi Ohsawa, Ryo Fukuda