Patents by Inventor Kiichi Makuta

Kiichi Makuta 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: 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
  • Patent number: 6888751
    Abstract: A nonvolatile semiconductor memory device includes a memory array which comprises a plurality of memory cells of a type wherein predetermined voltages are applied to selected memory cells to change their threshold voltages, whereby information are stored therein according to the difference between the threshold voltages, and whose some memory cells are used as spare memory cells. The nonvolatile semiconductor memory device is provided with a latch circuit connected to each bit line of the memory array through a transmission switch. The memory array is capable of storing therein at least substitutional information for replacing a defective bit by the spare memory cell. The substitutional information is transferred from the memory array to the latch circuit through the transmission switch and held in the latch circuit.
    Type: Grant
    Filed: February 12, 2003
    Date of Patent: May 3, 2005
    Assignee: Renesas Technology Corp.
    Inventors: Kiichi Makuta, Akihiro Fujita, Hideo Kasai, Masashii Wada, Atsushi Toukairin
  • 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
  • Publication number: 20030117847
    Abstract: A nonvolatile semiconductor memory device includes a memory array which comprises a plurality of memory cells of a type wherein predetermined voltages are applied to selected memory cells to change their threshold voltages, whereby information are stored therein according to the difference between the threshold voltages, and whose some memory cells are used as spare memory cells. The nonvolatile semiconductor memory device is provided with a latch circuit connected to each bit line of the memory array through a transmission switch. The memory array is capable of storing therein at least substitutional information for replacing a defective bit by the spare memory cell. The substitutional information is transferred from the memory array to the latch circuit through the transmission switch and held in the latch circuit.
    Type: Application
    Filed: February 12, 2003
    Publication date: June 26, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Kiichi Makuta, Akihiro Fujita, Hideo Kasai, Masashi Wada, Atsushi Toukairin
  • 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
  • Patent number: 6556479
    Abstract: A nonvolatile semiconductor memory device includes a memory array which comprises a plurality of memory cells of a type wherein predetermined voltages are applied to selected memory cells to change their threshold voltages, whereby information are stored therein according to the difference between the threshold voltages, and whose some memory cells are used as spare memory cells. The nonvolatile semiconductor memory device is provided with a latch circuit connected to each bit line of the memory array through a transmission switch. The memory array is capable of storing therein at least substitutional information for replacing a defective bit by the spare memory cell. The substitutional information is transferred from the memory array to the latch circuit through the transmission switch and held in the latch circuit.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: April 29, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Kiichi Makuta, Akihiro Fujita, Hideo Kasai, Masashii Wada, Atsushi Toukairin
  • Patent number: 6480415
    Abstract: A nonvolatile semiconductor memory device includes a memory array which comprises a plurality of memory cells of a type wherein predetermined voltages are applied to selected memory cells to change their threshold voltages, whereby information are stored therein according to the difference between the threshold voltages, and whose some memory cells are used as spare memory cells. The nonvolatile semiconductor memory device is provided with a latch circuit connected to each bit line of the memory array through a transmission switch. The memory array is capable of storing therein at least substitutional information for replacing a defective bit by the spare memory cell. The substitutional information is transferred from the memory array to the latch circuit through the transmission switch and held in the latch circuit.
    Type: Grant
    Filed: October 29, 2001
    Date of Patent: November 12, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Kiichi Makuta, Akihiro Fujita, Hideo Kasai, Masashii Wada, Atsushi Toukairin
  • Publication number: 20020054507
    Abstract: A nonvolatile semiconductor memory device includes a memory array which comprises a plurality of memory cells of a type wherein predetermined voltages are applied to selected memory cells to change their threshold voltages, whereby information are stored therein according to the difference between the threshold voltages, and whose some memory cells are used as spare memory cells. The nonvolatile semiconductor memory device is provided with a latch circuit connected to each bit line of the memory array through a transmission switch. The memory array is capable of storing therein at least substitutional information for replacing a defective bit by the spare memory cell. The substitutional information is transferred from the memory array to the latch circuit through the transmission switch and held in the latch circuit.
    Type: Application
    Filed: October 29, 2001
    Publication date: May 9, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Kiichi Makuta, Akihiro Fujita, Hideo Kasai, Masashi Wada, Atsushi Toukairin
  • 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
  • Patent number: 5610856
    Abstract: An increase in the GND resistance and a drop in the resistance against electromigration are minimized when the ground voltage lines for shunting are finely constituted by using an Al wiring of the same layer as the pad layer, owing to the employment of a layout in which the arrangement of connection holes 24, 26 in a pad layer connected to one (data line) of the complementary data lines and the arrangement of connection holes in a pad layer connected to the other one (data line bar) of the complementary data lines, are inverted from each other every two bits of memory cells in the SRAM along the direction in which the complementary data lines extend.
    Type: Grant
    Filed: March 4, 1996
    Date of Patent: March 11, 1997
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Keiichi Yoshizumi, Satoru Haga, Shuji Ikeda, Kiichi Makuta, Takeshi Fukazawa