Patents by Inventor Tetsufumi Tanamoto

Tetsufumi Tanamoto 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).

  • Publication number: 20140372671
    Abstract: According to an embodiment, an authentication device includes an acquiring unit, a predicting unit, and an authenticating unit. The acquiring unit is configured to acquire performance information of a first device that is a device to be authenticated. The predicting unit is configured to predict performance information of a second device that is a device being a reference for authentication according to a change with time from initial performance information. The authenticating unit is configured to perform an authentication process of determining whether or not the first device falls into the second device on a basis of a degree of agreement between the performance information acquired by the acquiring unit and the performance information predicted by the predicting unit.
    Type: Application
    Filed: February 26, 2014
    Publication date: December 18, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tetsufumi TANAMOTO, Takao Marukame, Shinichi Yasuda, Yuichiro Mitani, Atsushi Shimbo, Tatsuya Kishi
  • Publication number: 20140332895
    Abstract: A random number generation device includes: a first source region; a first drain region; a first channel region provided between the first source region and the first drain region; a first insulating film provided on the first channel region; and a first gate electrode provided on the first insulating film. The first insulating film has a trap capturing and releasing a charge, and a tensile or compressive stress is applied in a direction of a gate length to at least one of the first channel region and the first insulating film.
    Type: Application
    Filed: July 29, 2014
    Publication date: November 13, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shigeki KOBAYASHI, Ken UCHIDA, Shinobu FUJITA, Tetsufumi TANAMOTO
  • Patent number: 8874631
    Abstract: A random number generation apparatus includes: a random noise generation element comprising a source region and a drain region, a tunnel insulation film, a gate electrode, and a charge trap portion provided between the tunnel insulation film and the gate electrode and being capable of trapping charges, random noise being generated in a drain current flowing between the source region and the drain region on the basis of charges trapped in the charge trap portion; a random number conversion circuit for converting random noise generated from the random noise generation element to a random number; a first test circuit for performing a random number test to test quality of the random number output from the random number conversion circuit; and an initialization circuit for pulling out charges in the charge trap portion of the random noise generation element to the semiconductor substrate through the tunnel insulation film and thereby initializing the charge trap portion.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: October 28, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Mari Matsumoto, Tetsufumi Tanamoto, Shinichi Yasuda
  • Publication number: 20140301136
    Abstract: A magnetic memory according to an embodiment includes: a multilayer structure including a semiconductor layer and a first ferromagnetic layer; a first wiring line electrically connected to the semiconductor layer; a second wiring line electrically connected to the first ferromagnetic layer; and a voltage applying unit electrically connected between the first wiring line and the second wiring line to apply a first voltage between the semiconductor layer and the first ferromagnetic layer during a write operation, a magnetization direction of the first ferromagnetic layer being switchable by applying the first voltage.
    Type: Application
    Filed: March 11, 2014
    Publication date: October 9, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tomoaki INOKUCHI, Mizue ISHIKAWA, Hideyuki SUGIYAMA, Tetsufumi TANAMOTO, Akira TAKASHIMA, Yoshiaki SAITO
  • Patent number: 8856199
    Abstract: A random number generator circuit includes: an element generating and outputting physical random numbers; a digitizing circuit digitizing the physical random numbers to output a random number sequence tested by a testing circuit; and an error correcting code circuit including a shift register having the random number sequence input thereto, a multiplier multiplying the stored random number sequence by an error-correcting-code generating matrix, and a selector switch outputting one of an output of the shift register and an output of the multiplier in accordance with a test result obtained by the testing circuit. The error correcting code circuit outputs the output of the multiplier as a corrected random number sequence from the selector switch when the result of a test conducted by the testing circuit indicates a rejection. The testing circuit tests the corrected random number sequence when the result of the test indicates a rejection.
    Type: Grant
    Filed: November 22, 2011
    Date of Patent: October 7, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tetsufumi Tanamoto, Mari Matsumoto, Shinobu Fujita, Kazutaka Ikegami
  • Publication number: 20140293692
    Abstract: A memory system according to an embodiment may have an integration unit and a prediction unit. The integration unit may detect substrate current flowing through a substrate of a non-volatile memory when the non-volatile memory with a memory cell, which has binary or multivalued being the binary or more is written/erased. The integration unit may records an integration value of the detected substrate current into a storage. The prediction unit may predict a lifetime of the non-volatile memory based on the integration value which is recorded on the storage.
    Type: Application
    Filed: February 24, 2014
    Publication date: October 2, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Jiezhi CHEN, Tetsufumi Tanamoto, Yuichiro Mitani, Takao Marukame
  • Publication number: 20140143292
    Abstract: According to one embodiment, a random number generating circuit includes first to N-th oscillating circuits (N is a natural number equal to 2 or greater), first to N-th latch circuits that latch outputs of the first to N-th oscillating circuits by a first clock having a first frequency, first to N-th exclusive OR circuits, (N+1)-th to (2×N)-th latch circuits that latch outputs of the first to N-th exclusive OR circuits by the first clock, an (N+1)-th exclusive OR circuit that outputs an exclusive OR of outputs of the (N+1)-th to (2×N)-th latch circuits, and an M-bit shift register that converts serial data output from the (N+1)-th exclusive OR circuit into M-bit parallel data (M is a natural number equal to 2 or greater) by a second clock having a second frequency.
    Type: Application
    Filed: November 21, 2013
    Publication date: May 22, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shinichi YASUDA, Tetsufumi Tanamoto, Noriko Inoue, Akira Tomita, Ryusuke Murakami, Atsushi Shimbo
  • Publication number: 20140117427
    Abstract: A stacked structure according to an embodiment includes: a semiconductor layer; a first layer formed on the semiconductor layer, the first layer containing at least one element selected from Zr, Ti, and Hf, the first layer being not thinner than a monoatomic layer and not thicker than a pentatomic layer; a tunnel barrier layer formed on the first layer; and a magnetic layer formed on the tunnel barrier layer.
    Type: Application
    Filed: September 30, 2013
    Publication date: May 1, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki SAITO, Tomoaki Inokuchi, Mizue Ishikawa, Hideyuki Sugiyama, Tetsufumi Tanamoto
  • Patent number: 8681033
    Abstract: According to an embodiment, an analog-to-digital converter includes a voltage generating unit to generate comparative voltages; and comparators. Each comparator compares any one of the comparative voltages with an analog input voltage and output a digital signal. Each comparator includes a differential pair circuit to detect a potential difference between two inputs. The differential pair circuit includes first and second circuit portions. The first circuit portion includes a first transistor having a gate to which one input is supplied; and a resistor connected in series with the first transistor. The second circuit portion includes a second transistor having a gate to which the other input is supplied and forms a differential pair with the first transistor; and a variable resistor connected in series with the second transistor. The variable resistor includes variable resistive elements each having a resistance value variably set according to a control signal.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: March 25, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takao Marukame, Tetsufumi Tanamoto, Atsuhiro Kinoshita, Tomoaki Inokuchi, Masamichi Suzuki, Yoshiaki Saito
  • Patent number: 8681034
    Abstract: According to an embodiment, an analog-to-digital converter includes a voltage generating unit, and a plurality of comparators. The voltage generating unit is configured to divide a reference voltage by a plurality of variable resistors to generate a plurality of comparative voltages. Each of the plurality of comparator is configured to compare any one of the plurality of comparative voltages with an analog input voltage and output a digital signal based on a result of a comparison between the comparative voltage and the analog input voltage. Each of the plurality of variable resistors includes a plurality of variable resistive elements that are connected in series, and each of the plurality of variable resistive elements has a resistance value that is variably set according to an external signal.
    Type: Grant
    Filed: June 28, 2012
    Date of Patent: March 25, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takao Marukame, Tetsufumi Tanamoto, Atsuhiro Kinoshita, Tomoaki Inokuchi, Masamichi Suzuki, Yoshiaki Saito
  • Patent number: 8611143
    Abstract: A memory circuit according to an embodiment includes: a first transistor including a first source/drain electrode, a second source/drain electrode, and a first gate electrode; a second transistor including a third source/drain electrode connected to the second source/drain electrode, a fourth source/drain electrode, and a second gate electrode; a third transistor and a fourth transistor forming an inverter circuit, the third transistor including a fifth source/drain electrode, a sixth source/drain electrode, and a third gate electrode connected to the second source/drain electrode, the fourth transistor including a seventh source/drain electrode connected to the sixth source/drain electrode, an eighth source/drain electrode, and a fourth gate electrode connected to the second source/drain electrode; and an output terminal connected to the sixth source/drain electrode.
    Type: Grant
    Filed: February 23, 2012
    Date of Patent: December 17, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideyuki Sugiyama, Masato Oda, Shinobu Fujita, Tetsufumi Tanamoto, Mizue Ishikawa, Takao Marukame, Tomoaki Inokuchi, Yoshiaki Saito
  • Patent number: 8610196
    Abstract: In a memory of an embodiment, first and second P-channel transistors are formed on a first semiconductor region, and each of the first and second P-channel transistors has a structure formed by stacking a first insulating film, a first floating gate, a second insulating film, a second floating gate, a third insulating film, and a first control gate in this order on the first semiconductor region. In the memory, first and second N-channel transistors are formed on a second semiconductor region, and each of the first and second N-channel transistors has a structure formed by stacking a fourth insulating film, a third floating gate, a fifth insulating film, a fourth floating gate, a sixth insulating film, and a second control gate in this order on the second semiconductor region.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: December 17, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tetsufumi Tanamoto, Kosuke Tatsumura, Kiwamu Sakuma, Atsuhiro Kinoshita, Shinobu Fujita, Koichi Muraoka
  • Patent number: 8578318
    Abstract: In one embodiment, a method for implementing a circuit design for an integrated circuit includes: (a) obtaining a first wiring to satisfy a given operating frequency; (b) calculating a maximum bypass wiring length based on the given operating frequency and a critical path of the first wiring; (c) obtaining a second wiring by bypassing the first wiring using wires other than wires of the first wiring in a first wiring group, wherein wiring of the integrated circuit is categorized into a plurality of wiring groups, and the first wiring is included in the first wiring group of the categorized wiring groups; and (d) replacing the first wiring with the second wiring, if a difference between the second wiring and the first wiring is not larger than the maximum bypass wiring length, and not replacing the first wiring if said difference is larger than the maximum bypass wiring length.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: November 5, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kumiko Nomura, Shinichi Yasuda, Shinobu Fujita, Keiko Abe, Tetsufumi Tanamoto, Kazutaka Ikegami, Masato Oda
  • Patent number: 8553464
    Abstract: An aspect of the present embodiment, there is provided a nonvolatile programmable logic switch including a first memory cell transistor, a second memory cell transistor, a pass transistor and a first substrate electrode applying a substrate voltage to the pass transistor, wherein a writing voltage is applied to the first wiring, a first voltage is applied to one of a second wiring and a third wiring and a second voltage which is lower than the first voltage is applied to the other of the second wiring and the third wiring, and the first substrate voltage which is higher than the second voltage and lower than the first voltage is applied to a well of the pass transistor, when data is written into the first memory cell transistor or the second memory cell transistor.
    Type: Grant
    Filed: September 22, 2011
    Date of Patent: October 8, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshifumi Nishi, Daisuke Hagishima, Shinichi Yasuda, Tetsufumi Tanamoto, Takahiro Kurita, Atsuhiro Kinoshita, Shinobu Fujita
  • Publication number: 20130076551
    Abstract: According to an embodiment, an analog-to-digital converter includes a voltage generating unit to generate comparative voltages; and comparators. Each comparator compares any one of the comparative voltages with an analog input voltage and output a digital signal. Each comparator includes a differential pair circuit to detect a potential difference between two inputs. The differential pair circuit includes first and second circuit portions. The first circuit portion includes a first transistor having a gate to which one input is supplied; and a resistor connected in series with the first transistor. The second circuit portion includes a second transistor having a gate to which the other input is supplied and forms a differential pair with the first transistor; and a variable resistor connected in series with the second transistor. The variable resistor includes variable resistive elements each having a resistance value variably set according to a control signal.
    Type: Application
    Filed: June 27, 2012
    Publication date: March 28, 2013
    Inventors: Takao MARUKAME, Tetsufumi Tanamoto, Atsuhiro Kinoshita, Tomoaki Inokuchi, Masamichi Suzuki, Yoshiaki Saito
  • Publication number: 20130076550
    Abstract: According to an embodiment, an analog-to-digital converter includes a voltage generating unit, and a plurality of comparators. The voltage generating unit is configured to divide a reference voltage by a plurality of variable resistors to generate a plurality of comparative voltages. Each of the plurality of comparator is configured to compare any one of the plurality of comparative voltages with an analog input voltage and output a digital signal based on a result of a comparison between the comparative voltage and the analog input voltage. Each of the plurality of variable resistors includes a plurality of variable resistive elements that are connected in series, and each of the plurality of variable resistive elements has a resistance value that is variably set according to an external signal.
    Type: Application
    Filed: June 28, 2012
    Publication date: March 28, 2013
    Inventors: Takao MARUKAME, Tetsufumi Tanamoto, Atsuhiro Kinoshita, Tomoaki Inokuchi, Masamichi Suzuki, Yoshiaki Saito
  • Publication number: 20130075843
    Abstract: A spin transistor according to an embodiment includes: a first magnetic layer formed above a substrate and serving as one of a source and a drain; an insulating film having a lower face facing to an upper face of the first magnetic layer, an upper face opposed to the lower face, and a side face different from the lower and upper faces, the insulating film being formed on the upper face of the first magnetic layer and serving as a channel; a second magnetic layer formed on the upper face of the insulating film and serving as the other one of the source and the drain; a gate electrode formed along the side face of the insulating film; and a gate insulating film located between the gate electrode and the side face of the insulating film.
    Type: Application
    Filed: June 18, 2012
    Publication date: March 28, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tomoaki Inokuchi, Takao Marukame, Tetsufumi Tanamoto, Hideyuki Sugiyama, Mizue Ishikawa, Yoshiaki Saito
  • Patent number: 8405443
    Abstract: A pass transistor circuit according to an embodiment includes: a first input/output terminal connected to a first signal line; a second input/output terminal connected to a second signal line; a first device having a first terminal connected to a first power supply and a second terminal; a second device having a third terminal connected to the second terminal and a fourth terminal connected to a second power supply; a first transistor having one of source/drain connected to the second terminal, a gate receiving a first control signal; and a second transistor having a gate connected to the other one of source/drain of the first transistor, one of source/drain connected to the first input/output terminal, and the other one of source/drain connected to the second input/output terminal. One of the first and second devices is a nonvolatile memory device, the other one of the first and second devices is a MOSFET.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: March 26, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideyuki Sugiyama, Tetsufumi Tanamoto, Takao Marukame, Mizue Ishikawa, Tomoaki Inokuchi, Yoshiaki Saito
  • Publication number: 20130069134
    Abstract: In a memory of an embodiment, first and second P-channel transistors are formed on a first semiconductor region, and each of the first and second P-channel transistors has a structure formed by stacking a first insulating film, a first floating gate, a second insulating film, a second floating gate, a third insulating film, and a first control gate in this order on the first semiconductor region. In the memory, first and second N-channel transistors are formed on a second semiconductor region, and each of the first and second N-channel transistors has a structure formed by stacking a fourth insulating film, a third floating gate, a fifth insulating film, a fourth floating gate, a sixth insulating film, and a second control gate in this order on the second semiconductor region.
    Type: Application
    Filed: September 10, 2012
    Publication date: March 21, 2013
    Inventors: Tetsufumi TANAMOTO, Kosuke Tatsumura, Kiwamu Sakuma, Atsuhiro Kinoshita, Shinobu Fujita, Koichi Muraoka
  • Publication number: 20130055189
    Abstract: In one embodiment, a method for implementing a circuit design for an integrated circuit includes: (a) obtaining a first wiring to satisfy a given operating frequency; (b) calculating a maximum bypass wiring length based on the given operating frequency and a critical path of the first wiring; (c) obtaining a second wiring by bypassing the first wiring using wires other than wires of the first wiring in a first wiring group, wherein wiring of the integrated circuit is categorized into a plurality of wiring groups, and the first wiring is included in the first wiring group of the categorized wiring groups; and (d) replacing the first wiring with the second wiring, if a difference between the second wiring and the first wiring is not larger than the maximum bypass wiring length, and not replacing the first wiring if said difference is larger than the maximum bypass wiring length.
    Type: Application
    Filed: July 30, 2012
    Publication date: February 28, 2013
    Inventors: Kumiko Nomura, Shinichi Yasuda, Shinobu Fujita, Keiko Abe, Tetsufumi Tanamoto, Kazutaka Ikegami, Masato Oda