Patents by Inventor Tadashi Yasufuku
Tadashi Yasufuku 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: 10672487Abstract: A semiconductor memory device includes first and second memory cells, each of which includes a charge storage layer, a first bit line that is connected to the first memory cell, and a second bit line that is connected to the second memory cell. A writing operation includes multiple loops of a programming operation and a verification operation, and first data is written in the first memory cell, and second data different from the first data is written in the second memory cell through the writing operation. In a first loop of the writing operation, a first voltage is applied to the first bit line and the second bit line is maintained in an electrically floating state during the programming operation, and a verification operation relating to the second data is not performed and a verification operation relating to the first data is performed.Type: GrantFiled: July 1, 2019Date of Patent: June 2, 2020Assignee: Toshiba Memory CorporationInventors: Hiroshi Maejima, Koji Hosono, Tadashi Yasufuku, Noboru Shibata
-
Patent number: 10553283Abstract: According to one embodiment, a semiconductor storage device includes a first plane having a first plurality of memory cells, a second plane having a second plurality of memory cells, first bit lines which are connected to the first plane, second bit lines which are connected to the second plane, a plurality of first sense amplifiers which charge the plurality of first bit lines, and a plurality of second sense amplifiers which charge the plurality of second bit lines. When the first and second planes operate in parallel, a total sum of currents supplied to the plurality of first bit lines from the plurality of first sense amplifiers and currents supplied to the plurality of second bit lines from the plurality of second sense amplifiers reaches a first current value, then decreases to a second current value, and then increases to a third current value.Type: GrantFiled: August 29, 2018Date of Patent: February 4, 2020Assignee: TOSHIBA MEMORY CORPORATIONInventors: Yoko Deguchi, Kosuke Yanagidaira, Tadashi Yasufuku, Takuyo Kodama
-
Publication number: 20190355421Abstract: According to one embodiment, a semiconductor storage device includes a first plane having a first plurality of memory cells, a second plane having a second plurality of memory cells, first bit lines which are connected to the first plane, second bit lines which are connected to the second plane, a plurality of first sense amplifiers which charge the plurality of first bit lines, and a plurality of second sense amplifiers which charge the plurality of second bit lines. When the first and second planes operate in parallel, a total sum of currents supplied to the plurality of first bit lines from the plurality of first sense amplifiers and currents supplied to the plurality of second bit lines from the plurality of second sense amplifiers reaches a first current value, then decreases to a second current value, and then increases to a third current value.Type: ApplicationFiled: August 29, 2018Publication date: November 21, 2019Inventors: Yoko DEGUCHI, Kosuke YANAGIDAIRA, Tadashi YASUFUKU, Takuyo KODAMA
-
Publication number: 20190325973Abstract: A semiconductor memory device includes first and second memory cells, each of which includes a charge storage layer, a first bit line that is connected to the first memory cell, and a second bit line that is connected to the second memory cell. A writing operation includes multiple loops of a programming operation and a verification operation, and first data is written in the first memory cell, and second data different from the first data is written in the second memory cell through the writing operation. In a first loop of the writing operation, a first voltage is applied to the first bit line and the second bit line is maintained in an electrically floating state during the programming operation, and a verification operation relating to the second data is not performed and a verification operation relating to the first data is performed.Type: ApplicationFiled: July 1, 2019Publication date: October 24, 2019Inventors: Hiroshi MAEJIMA, Koji HOSONO, Tadashi YASUFUKU, Noboru SHIBATA
-
Patent number: 10381096Abstract: A semiconductor memory device includes first and second memory cells, each of which includes a charge storage layer, a first bit line that is connected to the first memory cell, and a second bit line that is connected to the second memory cell. A writing operation includes multiple loops of a programming operation and a verification operation, and first data is written in the first memory cell, and second data different from the first data is written in the second memory cell through the writing operation. In a first loop of the writing operation, a first voltage is applied to the first bit line and the second bit line is maintained in an electrically floating state during the programming operation, and a verification operation relating to the second data is not performed and a verification operation relating to the first data is performed.Type: GrantFiled: May 23, 2018Date of Patent: August 13, 2019Assignee: Toshiba Memory CorporationInventors: Hiroshi Maejima, Koji Hosono, Tadashi Yasufuku, Noboru Shibata
-
Publication number: 20180301197Abstract: A semiconductor memory device includes first and second memory cells, each of which includes a charge storage layer, a first bit line that is connected to the first memory cell, and a second bit line that is connected to the second memory cell. A writing operation includes multiple loops of a programming operation and a verification operation, and first data is written in the first memory cell, and second data different from the first data is written in the second memory cell through the writing operation. In a first loop of the writing operation, a first voltage is applied to the first bit line and the second bit line is maintained in an electrically floating state during the programming operation, and a verification operation relating to the second data is not performed and a verification operation relating to the first data is performed.Type: ApplicationFiled: May 23, 2018Publication date: October 18, 2018Inventors: Hiroshi MAEJIMA, Koji HOSONO, Tadashi YASUFUKU, Noboru SHIBATA
-
Patent number: 9984761Abstract: A semiconductor memory device includes first and second memory cells, each of which includes a charge storage layer, a first bit line that is connected to the first memory cell, and a second bit line that is connected to the second memory cell. A writing operation includes multiple loops of a programming operation and a verification operation, and first data is written in the first memory cell, and second data different from the first data is written in the second memory cell through the writing operation. In a first loop of the writing operation, a first voltage is applied to the first bit line and the second bit line is maintained in an electrically floating state during the programming operation, and a verification operation relating to the second data is not performed and a verification operation relating to the first data is performed.Type: GrantFiled: August 10, 2016Date of Patent: May 29, 2018Assignee: Toshiba Memory CorporationInventors: Hiroshi Maejima, Koji Hosono, Tadashi Yasufuku, Noboru Shibata
-
Publication number: 20170178739Abstract: A semiconductor memory device includes first and second memory cells, each of which includes a charge storage layer, a first bit line that is connected to the first memory cell, and a second bit line that is connected to the second memory cell. A writing operation includes multiple loops of a programming operation and a verification operation, and first data is written in the first memory cell, and second data different from the first data is written in the second memory cell through the writing operation. In a first loop of the writing operation, a first voltage is applied to the first bit line and the second bit line is maintained in an electrically floating state during the programming operation, and a verification operation relating to the second data is not performed and a verification operation relating to the first data is performed.Type: ApplicationFiled: August 10, 2016Publication date: June 22, 2017Inventors: Hiroshi MAEJIMA, Koji HOSONO, Tadashi YASUFUKU, Noboru SHIBATA
-
Patent number: 9036443Abstract: A booster circuit is configured, such that: in response to a reading request for reading data from a flash memory, when a voltage of an output terminal detected by a voltage detection circuit is not higher than a voltage, an oscillator outputs a control clock signal of predetermined on time and off time to a transistor of a boost converter to perform switching control of the transistor; and when the voltage detection circuit detects that the voltage of the output terminal reaches a voltage, an oscillator outputs a control clock signal of an on time and an off time input from a selection circuit to a transistor of a boost converter to perform switching control of the transistor.Type: GrantFiled: May 11, 2012Date of Patent: May 19, 2015Assignee: THE UNIVERSITY OF TOKYOInventors: Ken Takeuchi, Teruyoshi Hatanaka, Koichi Ishida, Tadashi Yasufuku, Makoto Takamiya, Takayasu Sakurai
-
Publication number: 20150078102Abstract: A nonvolatile semiconductor memory device includes a first data latch, a second data latch, and a data bus between the first and second data latches. A first transistor is electrically connected between the first data latch and the data bus and a second transistor is electrically connected between the data bus and the second data latch. A control unit controls charging of the data bus based on an output of the first data latch.Type: ApplicationFiled: February 24, 2014Publication date: March 19, 2015Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Tadashi YASUFUKU
-
Patent number: 8742838Abstract: The interposer 30 is disposed on an upper surface of the stacked structure 24 formed by stacking a plurality of a DRAM chip 20 and a plurality of a flash memory chip 22. Thus down-size of an entire device is accomplished. A boost converter having an inductor is used as a voltage boost circuit 40. Thus down-size of the entire device is accomplished.Type: GrantFiled: April 17, 2009Date of Patent: June 3, 2014Assignee: The University of TokyoInventors: Ken Takeuchi, Tadashi Yasufuku, Koichi Ishida, Makoto Takamiya, Takayasu Sakurai
-
Publication number: 20140104952Abstract: A booster circuit is configured, such that: in response to a reading request for reading data from a flash memory, when a voltage of an output terminal detected by a voltage detection circuit is not higher than a voltage, an oscillator outputs a control clock signal of predetermined on time and off time to a transistor of a boost converter to perform switching control of the transistor; and when the voltage detection circuit detects that the voltage of the output terminal reaches a voltage, an oscillator outputs a control clock signal of an on time and an off time input from a selection circuit to a transistor of a boost converter to perform switching control of the transistor.Type: ApplicationFiled: May 11, 2012Publication date: April 17, 2014Applicant: THE UNIVERSITY OF TOKYOInventors: Ken Takeuchi, Teruyoshi Hatanaka, Koichi Ishida, Tadashi Yasufuku, Makoto Takamiya, Takayasu Sakurai
-
Patent number: 8514013Abstract: The channel number detecting circuit detects the operation channel number based on the output terminal voltage after falling down when the output terminal voltage falls down during the voltage boosting control, and the switching control circuit generates the control clock signal having the on-time and the off-time adjusted based on the operation channel number and performs the voltage boosting control using generating control clock signal. The voltage boosting control is properly performed based on the operation channel number when the operation channel number increase during performing the voltage boosting control. Thus boosting the power supply voltage up to a second voltage is accomplished.Type: GrantFiled: April 25, 2011Date of Patent: August 20, 2013Assignee: The University of TokyoInventors: Ken Takeuchi, Teruyoshi Hatanaka, Koichi Ishida, Tadashi Yasufuku, Makoto Takamiya, Takayasu Sakurai
-
Publication number: 20110298534Abstract: The channel number detecting circuit 50 detects the operation channel number Nch based on the the output terminal voltage Vpgm after falling down when the output terminal voltage Vpgm falls down during the voltage boosting control, and the switching control circuit 70 generates the control clock signal CLK having the on-time and the off-time adjusted based on the operation channel number Nch and performs the voltage boosting control using generating control clock signal CLK. The voltage boosting control is properly performed based on the operation channel number Nch when the operation channel number Nch increase during performing the voltage boosting control. Thus boosting the power supply voltage Vdd up to the voltage V2 is accomplished.Type: ApplicationFiled: April 25, 2011Publication date: December 8, 2011Applicant: THE UNIVERSITY OF TOKYOInventors: Ken TAKEUCHI, Teruyoshi HATANAKA, Koichi ISHIDA, Tadashi YASUFUKU, Makoto TAKAMIYA, Takayasu SAKURAI
-
Publication number: 20110260781Abstract: The interposer is disposed on an upper surface of the stacked structure formed by stacking a plurality of a DRAM chip and a plurality of a flash memory chip. Thus down-size of an entire device is accomplished. A boost converter having an inductor is used as a voltage boost circuit. Thus down-size of the entire device is accomplished in comparison to a voltage boost circuit using a charge pump connected in parallel with a plurality of a capacitance.Type: ApplicationFiled: April 17, 2009Publication date: October 27, 2011Applicant: THE UNIVERSITY OF TOKYOInventors: Ken Takeuchi, Tadashi Yasufuku, Koichi Ishida, Makoto Takamiya, Takayasu Sakurai