Patents by Inventor Takashi Yamaki

Takashi Yamaki 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: 20060239072
    Abstract: Disclosed here is a method for speeding up data writing and reducing power consumption by reducing the variation of the threshold voltage of each of non-volatile memory cells at data writing. When writing data in a memory cell, a voltage of about 8V is applied to the memory gate line, a voltage of about 5V is applied to the source line, a voltage of about 1.5V is applied to the selected gate line respectively. At that time, in the writing circuit, the writing pulse is 0, the writing latch output a High signal, and a NAND-circuit outputs a Low signal. And, a constant current of about 1 iA flows in a constant current source transistor and the bit line is discharged by a constant current of about 1 iA to flow a current in the memory cell.
    Type: Application
    Filed: June 23, 2006
    Publication date: October 26, 2006
    Inventors: Toshihiro Tanaka, Takashi Yamaki, Yutaka Shinagawa, Daisuke Okada, Digh Hisamoto, Kan Yasui, Tetsuya Ishimaru
  • Publication number: 20060220100
    Abstract: A semiconductor device includes a plurality of nonvolatile memory cells (1). Each of the nonvolatile memory cells comprises a MOS type first transistor section (3) used for information storage, and a MOS type second transistor section (4) which selects the first transistor section. The second transistor section has a bit line electrode (16) connected to a bit line, and a control gate electrode (18) connected to a control gate control line. The first transistor section has a source line electrode (10) connected to a source line, a memory gate electrode (14) connected to a memory gate control line, and a charge storage region (11) disposed directly below the memory gate electrode. A gate withstand voltage of the second transistor section is lower than that of the first transistor section.
    Type: Application
    Filed: May 2, 2006
    Publication date: October 5, 2006
    Inventors: Toshihiro Tanaka, Yukiko Umemoto, Mitsuru Hiraki, Yutaka Shinagawa, Masamichi Fujito, Kazufumi Suzukawa, Hiroyuki Tanikawa, Takashi Yamaki, Yoshiaki Kamigaki, Shinichi Minami, Kozo Katayama, Nozomu Matsuzaki
  • Patent number: 7110295
    Abstract: An erasing current is distributed to reduce a load of an internal power circuit and to decrease the number of drivers for erase. A semiconductor data processing device has: a memory array having nonvolatile memory cells arrayed in a matrix and divided into a plurality of erase blocks each instructed to be erased together; and a control circuit, wherein the control circuit controls both of two kinds of erasing voltages applied to the nonvolatile memory cell in the erase block instructed to be erased together to select an erase sector from the erase block for performing erase for each erase sector, thereby performing the erase for each erase sector in time division. Time division erase can distribute an erasing current. Two kinds of erasing voltages are used to select the erase sector. No specific drivers need be provided for each erase sector.
    Type: Grant
    Filed: December 3, 2004
    Date of Patent: September 19, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Jiro Ishikawa, Takashi Yamaki, Toshihiro Tanaka, Yukiko Umemoto, Akira Kato
  • Patent number: 7085157
    Abstract: A method for speeding up data writing and reducing power consumption by reducing the variation of the threshold voltage of each of non-volatile memory cells at data writing. When writing data in a memory cell, a voltage of about 8V is applied to the memory gate line, a voltage of about 5V is applied to the source line, a voltage of about 1.5V is applied to the selected gate line respectively. At that time, in the writing circuit, the writing pulse is 0, the writing latch output a High signal, and a NAND-circuit outputs a Low signal. And, a constant current of about 1 ìA flows in a constant current source transistor and the bit line is discharged by a constant current of about 1 ìA to flow a current in the memory cell.
    Type: Grant
    Filed: March 22, 2004
    Date of Patent: August 1, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Toshihiro Tanaka, Takashi Yamaki, Yutaka Shinagawa, Daisuke Okada, Digh Hisamoto, Kan Yasui, Tetsuya Ishimaru
  • Patent number: 7057230
    Abstract: A semiconductor device includes a plurality of nonvolatile memory cells (1). Each of the nonvolatile memory cells comprises a MOS type first transistor section (3) used for information storage, and a MOS type second transistor section (4) which selects the first transistor section. The second transistor section has a bit line electrode (16) connected to a bit line, and a control gate electrode (18) connected to a control gate control line. The first transistor section has a source line electrode (10) connected to a source line, a memory gate electrode (14) connected to a memory gate control line, and a charge storage region (11) disposed directly below the memory gate electrode. A gate withstand voltage of the second transistor section is lower than that of the first transistor section.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: June 6, 2006
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Toshihiro Tanaka, Yukiko Umemoto, Mitsuru Hiraki, Yutaka Shinagawa, Masamichi Fujito, Kazufumi Suzukawa, Hiroyuki Tanikawa, Takashi Yamaki, Yoshiaki Kamigaki, Shinichi Minami, Kozo Katayama, Nozomu Matsuzaki
  • Publication number: 20060044871
    Abstract: The present invention is directed to realize both higher reading speed and assurance of the larger number of rewriting times for a nonvolatile memory. A semiconductor integrated circuit has a first nonvolatile memory area and a second nonvolatile memory area for storing information in accordance with a threshold voltage which varies.
    Type: Application
    Filed: August 3, 2005
    Publication date: March 2, 2006
    Inventors: Hiroyuki Tanikawa, Toshihiro Tanaka, Yutaka Shinagawa, Takashi Yamaki
  • Publication number: 20050285181
    Abstract: In a non-volatile semiconductor memory device using a charge storage film, it is intended to prevent a sequence disturb such as an erroneous write or erase of another memory cell on one and same word line which occurs depending on a bias transition path in stand-by state and write state. In connection with rise and fall of a word line bias, the present invention adopts a procedure such that a diffusion region voltage Vs on a memory transistor side is changed, and after the voltage Vs passes a certain intermediate value Vsx, a gate voltage Vmg of the memory transistor is changed. Alternatively, there is adopted a procedure such that the gate voltage Vmg of the memory transistor is changed, and after the voltage Vmg passes a certain intermediate value Vmgx, the diffusion layer voltage Vs on the memory transistor side is changed.
    Type: Application
    Filed: June 8, 2005
    Publication date: December 29, 2005
    Inventors: Kan Yasui, Digh Hisamoto, Toshihiro Tanaka, Takashi Yamaki
  • Publication number: 20050270851
    Abstract: A data processing device which selects either emission of electrons from a nonvolatile memory cell or injection of electrons into it for each bit. A memory array includes a plurality of nonvolatile memory cells each having a pair of a first MOS transistor and a second MOS transistor where the first transistor has a charge retention layer and a memory gate and is used for data storage and the second transistor has a control gate and selectively connects the first transistor to a bit line. When negative voltage is applied to a memory gate, electrons held by a charge retention layer are emitted through hot carriers generated in a nonvolatile memory cell channel region for erasing; and when positive voltage is applied to the memory gate, electrons are injected into the charge retention layer through hot carriers generated in the nonvolatile memory cell channel region for writing and controls the generation and suppression of hot carriers by means of bit line voltage on each bit line.
    Type: Application
    Filed: June 1, 2005
    Publication date: December 8, 2005
    Inventors: Akira Kato, Toshihiro Tanaka, Takashi Yamaki
  • Publication number: 20050265114
    Abstract: Disclosed is a nonvolatile memory with a shortened total write time, capable of stably writing data by making a write current constant while reducing fluctuations in a voltage generated by a booster circuit. In a nonvolatile memory such as a flash memory, data is determined at the time of writing operation. While skipping a bit corresponding to write data having the logic “1” (or logic “0”), writing operation to bits corresponding to write data having the logic “0” (or logic “1) is successively performed.
    Type: Application
    Filed: August 5, 2005
    Publication date: December 1, 2005
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Kazufumi Suzukawa, Masamichi Fujito, Takashi Yamaki, Kiichi Makuta, Masashi Wada, Yoshiki Kawajiri
  • Publication number: 20050258474
    Abstract: A semiconductor device includes a plurality of nonvolatile memory cells (1). Each of the nonvolatile memory cells comprises a MOS type first transistor section (3) used for information storage, and a MOS type second transistor section (4) which selects the first transistor section. The second transistor section has a bit line electrode (16) connected to a bit line, and a control gate electrode (18) connected to a control gate control line. The first transistor section has a source line electrode (10) connected to a source line, a memory gate electrode (14) connected to a memory gate control line, and a charge storage region (11) disposed directly below the memory gate electrode. A gate withstand voltage of the second transistor section is lower than that of the first transistor section.
    Type: Application
    Filed: July 22, 2002
    Publication date: November 24, 2005
    Inventors: Toshihiro Tanaka, Yukiko Umemoto, Mitsuru Hiraki, Yutaka Shinagawa, Masamichi Fujito, Kazufumi Suzukawa, Hiroyuki Tanikawa, Takashi Yamaki, Yoshiaki Kamigaki, Shinichi Minami, Kozo Katayama, Nozomu Matsuzaki
  • Patent number: 6963507
    Abstract: Disclosed is a nonvolatile memory with a shortened total write time, capable of stably writing data by making a write current constant while reducing fluctuations in a voltage generated by a booster circuit. In a nonvolatile memory such as a flash memory, data is determined at the time of writing operation. While skipping a bit corresponding to write data having the logic “1” (or logic “0”), writing operation to bits corresponding to write data having the logic “0” (or logic “1) is successively performed.
    Type: Grant
    Filed: April 21, 2003
    Date of Patent: November 8, 2005
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Kazufumi Suzukawa, Masamichi Fujito, Takashi Yamaki, Kiichi Makuta, Masashi Wada, Yoshiki Kawajiri
  • Publication number: 20050128815
    Abstract: An erasing current is distributed to reduce a load of an internal power circuit and to decrease the number of drivers for erase. A semiconductor data processing device has: a memory array having nonvolatile memory cells arrayed in a matrix and divided into a plurality of erase blocks each instructed to be erased together; and a control circuit, wherein the control circuit controls both of two kinds of erasing voltages applied to the nonvolatile memory cell in the erase block instructed to be erased together to select an erase sector from the erase block for performing erase for each erase sector, thereby performing the erase for each erase sector in time division. Time division erase can distribute an erasing current. Two kinds of erasing voltages are used to select the erase sector. No specific drivers need be provided for each erase sector.
    Type: Application
    Filed: December 3, 2004
    Publication date: June 16, 2005
    Inventors: Jiro Ishikawa, Takashi Yamaki, Toshihiro Tanaka, Yukiko Umemoto, Akira Kato
  • Publication number: 20040196695
    Abstract: Disclosed here is a method for speeding up data writing and reducing power consumption by reducing the variation of the threshold voltage of each of non-volatile memory cells at data writing. When writing data in a memory cell, a voltage of about 8V is applied to the memory gate line, a voltage of about 5V is applied to the source line, a voltage of about 1.5V is applied to the selected gate line respectively. At that time, in the writing circuit, the writing pulse is 0, the writing latch output a High signal, and a NAND-circuit outputs a Low signal. And, a constant current of about 1 iA flows in a constant current source transistor and the bit line is discharged by a constant current of about 1 iA to flow a current in the memory cell.
    Type: Application
    Filed: March 22, 2004
    Publication date: October 7, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Toshihiro Tanaka, Takashi Yamaki, Yutaka Shinagawa, Daisuke Okada, Digh Hisamoto, Kan Yasui, Tetsuya Ishimaru
  • Publication number: 20030206451
    Abstract: Disclosed is a nonvolatile memory with a shortened total write time, capable of stably writing data by making a write current constant while reducing fluctuations in a voltage generated by a booster circuit. In a nonvolatile memory such as a flash memory, data is determined at the time of writing operation. While skipping a bit corresponding to write data having the logic “1” (or logic “0”), writing operation to bits corresponding to write data having the logic “1” (or logic “1) is successively performed.
    Type: Application
    Filed: April 21, 2003
    Publication date: November 6, 2003
    Applicants: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Kazufumi Suzukawa, Masamichi Fujito, Takashi Yamaki, Kiichi Makuta, Masashi Wada, Yoshiki Kawajiri
  • Patent number: 6643193
    Abstract: A semiconductor device whose characteristics are highly reliably regulated for circuits whose desired characteristics need to be realized without being affect by unevenness in device characteristics is to be provided. A replica MOS transistor for amperage measurement connected to an external measuring terminal is provided. A delay circuit and other circuits whose desired characteristics are to be realized have a constant current source MOS transistor formed in the same process as the replica MOS transistor, and a trimming voltage vtri is commonly applied to the respective gates of the constant current source MOS transistor and the replica MOS transistor. Trimming data determined on the basis of an amperage measured from the external measuring terminal are stored into a memory means such as an electrically rewritable non-volatile memory or the like. The trimming data determine the trimming voltage vtri.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: November 4, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Takashi Yamaki, Kan Takeuchi, Mitsuru Hirakii, Toshihiro Tanaka, Yutaka Shinagawa, Masamichi Fujito
  • Patent number: 6567313
    Abstract: Disclosed is a nonvolatile memory with a shortened total write time, capable of stably writing data by making a write current constant while reducing fluctuations in a voltage generated by a booster circuit. In a nonvolatile memory such as a flash memory, data is determined at the time of writing operation. While skipping a bit corresponding to write data having the logic “1” (or logic “0”), writing operation to bits corresponding to write data having the logic “0” (or logic “1) is successively performed.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: May 20, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Kazufumi Suzukawa, Masamichi Fujito, Takashi Yamaki, Kiichi Makuta, Masashi Wada, Yoshiki Kawajiri
  • Publication number: 20030016566
    Abstract: A semiconductor device whose characteristics are highly reliably regulated for circuits whose desired characteristics need to be realized without being affect by unevenness in device characteristics is to be provided. A replica MOS transistor for amperage measurement connected to an external measuring terminal is provided. A delay circuit and other circuits whose desired characteristics are to be realized have a constant current source MOS transistor formed in the same process as the replica MOS transistor, and a trimming voltage vtri is commonly applied to the respective gates of the constant current source MOS transistor and the replica MOS transistor. Trimming data determined on the basis of an amperage measured from the external measuring terminal are stored into a memory means such as an electrically rewritable non-volatile memory or the like. The trimming data determine the trimming voltage vtri.
    Type: Application
    Filed: September 20, 2002
    Publication date: January 23, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Takashi Yamaki, Kan Takeuchi, Mitsuru Hiraki, Toshihiro Tanaka, Yutaka Shinagawa, Masamichi Fujito
  • Patent number: 6477090
    Abstract: A semiconductor device whose characteristics are highly reliably regulated for circuits whose desired characteristics need to be realized without being affect by unevenness in device characteristics is to be provided. A replica MOS transistor for amperage measurement connected to an external measuring terminal is provided. A delay circuit and other circuits whose desired characteristics are to be realized have a constant current source MOS transistor formed in the same process as the replica MOS transistor, and a trimming voltage vtri is commonly applied to the respective gates of the constant current source MOS transistor and the replica MOS transistor. Trimming data determined on the basis of an amperage measured from the external measuring terminal are stored into a memory means such as an electrically rewritable non-volatile memory or the like. The trimming data determine the trimming voltage vtri.
    Type: Grant
    Filed: August 28, 2001
    Date of Patent: November 5, 2002
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Takashi Yamaki, Kan Takeuchi, Mitsuru Hiraki, Toshihiro Tanaka, Yutaka Shinagawa, Masamichi Fujito
  • Publication number: 20020041527
    Abstract: Disclosed is a nonvolatile memory with a shortened total write time, capable of stably writing data by making a write current constant while reducing fluctuations in a voltage generated by a booster circuit. In a nonvolatile memory such as a flash memory, data is determined at the time of writing operation. While skipping a bit corresponding to write data having the logic “1” (or logic “0”), writing operation to bits corresponding to write data having the logic “0” (or logic “1) is successively performed.
    Type: Application
    Filed: September 28, 2001
    Publication date: April 11, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Kazufumi Suzukawa, Masamichi Fujito, Takashi Yamaki, Kiichi Makuta, Masashi Wada, Yoshiki Kawajiri
  • Publication number: 20020027233
    Abstract: A semiconductor device whose characteristics are highly reliably regulated for circuits whose desired characteristics need to be realized without being affect by unevenness in device characteristics is to be provided. A replica MOS transistor for amperage measurement connected to an external measuring terminal is provided. A delay circuit and other circuits whose desired characteristics are to be realized have a constant current source MOS transistor formed in the same process as the replica MOS transistor, and a trimming voltage vtri is commonly applied to the respective gates of the constant current source MOS transistor and the replica MOS transistor. Trimming data determined on the basis of an amperage measured from the external measuring terminal are stored into a memory means such as an electrically rewritable non-volatile memory or the like. The trimming data determine the trimming voltage vtri.
    Type: Application
    Filed: August 28, 2001
    Publication date: March 7, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Takashi Yamaki, Kan Takeuchi, Mitsuru Hirakii, Toshihiro Tanaka, Yutaka Shinagawa, Masamichi Fujito