Patents by Inventor Yutaka Shinagawa

Yutaka Shinagawa 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: 20040047223
    Abstract: A method for settling threshold voltages of word lines on a predetermined level in an erasing processing of a non-volatile semiconductor memory device so as to speed up the erasing processing. A word latch circuit is provided for each word line and the threshold voltage of each memory cell is managed for each word line in a selected memory block. Each word latch circuit is shared by a plurality of word lines so as to reduce the required chip area. A rewriting voltage is set for each finished non-volatile memory and the voltage information is stored in the boot area of the non-volatile memory, so that the voltage is recognized by the system each time the system is powered.
    Type: Application
    Filed: August 12, 2003
    Publication date: March 11, 2004
    Applicants: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Nozomu Matsuzaki, Kazuyoshi Shiba, Yasuhiro Taniguchi, Toshihiro Tanaka, Yutaka Shinagawa
  • 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
  • Patent number: 6542411
    Abstract: A nonvolatile memory includes a control register (CRG) for providing instructions as to basic operations such as writing, erasing, reading, etc., a boosted voltage attainment detecting circuit for detecting whether a voltage boosted by a booster circuit has reached a desired level, a circuit which counts the time required to apply each of write and erase voltages, and a circuit which detects the completion of the writing or erasing. Respective operations are automatically advanced by simple setting of the operation instructions to the control register. After the completion of the operations, an end flag (FLAG) provided within the control register is set to notify the completion of the writing or erasing.
    Type: Grant
    Filed: October 5, 2001
    Date of Patent: April 1, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Hiroyuki Tanikawa, Toshihiro Tanaka, Yutaka Shinagawa, Yoshiki Kawajiri, Masamichi Fujito
  • Patent number: 6519184
    Abstract: In a verify operation after a write or erase to check whether a memory cell threshold voltage is contained in a predetermined threshold voltage distribution, verify voltage is changed in three stages or more in a direction to mitigate the decision condition. This prevents non-convergence of write and erase operation and can complete the write or erase in a short time.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: February 11, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Toshihiro Tanaka, Hiroyuki Tanikawa, Masayoshi Nakano, Norio Oza, Koki Watanabe, Yutaka Shinagawa
  • 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
  • Publication number: 20030012052
    Abstract: A method for settling threshold voltages of word lines on a predetermined level in an erasing processing of a non-volatile semiconductor memory device so as to speed up the erasing processing. A word latch circuit is provided for each word line and the threshold voltage of each memory cell is managed for each word line in a selected memory block. Each word latch circuit is shared by a plurality of word lines so as to reduce the required chip area. A rewriting voltage is set for each finished non-volatile memory and the voltage information is stored in the boot area of the non-volatile memory, so that the voltage is recognized by the system each time the system is powered.
    Type: Application
    Filed: August 20, 2002
    Publication date: January 16, 2003
    Applicant: Hitachi, Ltd. and Hitachi ULSI Systems Co., Ltd.
    Inventors: Nozomu Matsuzaki, Kazuyoshi Shiba, Yasuhiro Taniguchi, Toshihiro Tanaka, Yutaka Shinagawa
  • Patent number: 6480418
    Abstract: The present invention proposes a non-volatile semiconductor storage, comprising a plurality of main bit lines, a plurality of sub bit lines connected to the main bit lines, and a plurality of memory cell arrays, each including a plurality of non-volatile semiconductor memory cells disposed like an array. Each of those memory cells has a source terminal, a drain terminal, and a control gate, and each source-drain path is connected to a sub bit line. Between a main bit line and a sub bit line connected to the main bit line is disposed the source-drain path of a first transistor, and the source-drain path of a second transistor is connected to the sub bit line.
    Type: Grant
    Filed: September 14, 2001
    Date of Patent: November 12, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Kazuyoshi Shiba, Kazufumi Suzukawa, Masamichi Fujito, Takayuki Oshima, Sonoko Abe, Kiyoshi Matsubara
  • 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: 20020159291
    Abstract: This inventing is intended to shorten data deletion time of a nonvolatile semiconductor memory such as a flash memory (EEPROM). When deleting data written to a memory cell MC0 among flash memory cells MC0 to MC2 formed on a semiconductor substrate PSUB through a separation region NiSO, a voltage of p type well PWL0 in which the memory cell MC0 is formed is raised to 10V and a voltage of the separation region NiSO is raised to 12V by using a voltage application unit different from a voltage application unit applying a voltage to the p type well PWL0. As a result, parasitic capacitances Ca1and Ca2 generated between p type wells PWL1 and PWL2 in which the unselected memory cells MC1 and MC2 are formed and the separation region NiSO, respectively, and a parasitic capacitance Cb generated between the separation region NiSO and the semiconductor substrate PSUB are charged by the voltage application units.
    Type: Application
    Filed: February 27, 2002
    Publication date: October 31, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Yukiko Umemoto, Toshihiro Tanaka, Hiroyuki Tanikawa, Yutaka Shinagawa
  • Publication number: 20020153917
    Abstract: A semiconductor integrated circuit (LSI) in which control information for determining a voltage or a width of a pulse produced itself can easily be set in parallel with other LSIs, and set information can be corrected easily. From an external evaluation device, a voltage of an expected value is supplied in overlapping manner to a plurality of LSIs each having a CPU and a flash memory. Each LSI incorporates a comparison circuit comparing an expected voltage value and a boosted voltage generated in itself. The CPU refers to a comparison result and optimizes control data in a data register for changing a boosted voltage. The CPU controls the comparison circuit and the data register and performs trimming in a self-completion manner, thereby making, trimming on a plurality of LSIs easily in a parallel manner and a total test time reduced.
    Type: Application
    Filed: February 27, 2002
    Publication date: October 24, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Masahiko Kimura, Isao Nakamura
  • Publication number: 20020154545
    Abstract: In a verify operation after a write or erase to check whether a memory cell threshold voltage is contained in a predetermined threshold voltage distribution, verify voltage is changed in three stages or more in a direction to mitigate the decision condition. This prevents non-convergence of write and erase operation and can complete the write or erase in a short time.
    Type: Application
    Filed: February 26, 2002
    Publication date: October 24, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Toshihiro Tanaka, Hiroyuki Tanikawa, Masayoshi Nakano, Norio Oza, Koki Watanabe, Yutaka Shinagawa
  • Patent number: 6459619
    Abstract: A method for settling threshold voltages of word lines on a predetermined level in an erasing processing of a non-volatile semiconductor memory device so as to speed up the erasing processing. A word latch circuit is provided for each word line and the threshold voltage of each memory cell is managed for-each word line in a selected memory block. Each word latch circuit is shared by a plurality of word lines so as to reduce the required chip area. A rewriting voltage is set for each finished non-volatile memory and the voltage information is stored in the boot area of the non-volatile memory, so that the voltage is recognized by the system each time the system is powered.
    Type: Grant
    Filed: November 7, 2001
    Date of Patent: October 1, 2002
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Nozomu Matsuzaki, Kazuyoshi Shiba, Yasuhiro Taniguchi, Toshihiro Tanaka, Yutaka Shinagawa
  • Publication number: 20020054510
    Abstract: A method for settling threshold voltages of word lines on a predetermined level in an erasing processing of a non-volatile semiconductor memory device so as to speed up the erasing processing. A word latch circuit is provided for each word line and the threshold voltage of each memory cell is managed for each word line in a selected memory block. Each word latch circuit is shared by a plurality of word lines so as to reduce the required chip area. A rewriting voltage is set for each finished non-volatile memory and the voltage information is stored in the boot area of the non-volatile memory, so that the voltage is recognized by the system each time the system is powered.
    Type: Application
    Filed: November 7, 2001
    Publication date: May 9, 2002
    Inventors: Nozomu Matsuzaki, Kazuyoshi Shiba, Yasuhiro Taniguchi, Toshihiro Tanaka, Yutaka Shinagawa
  • Publication number: 20020048193
    Abstract: The invention includes a control register (CRG) for providing instructions as to basic operations such as writing, erasing, reading, etc., a boosted voltage attainment detecting circuit for detecting whether a voltage boosted by a booster circuit has reached a desired level, a circuit which counts the time required to apply each of write and erase voltages, and a circuit which detects the completion of the writing or erasing. Respective operations are automatically advanced by simple setting of the operation instructions to the control register. After the completion of the operations, an end flag (FLAG) provided within the control register is set to notify the completion of the writing or erasing.
    Type: Application
    Filed: October 5, 2001
    Publication date: April 25, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Hiroyuki Tanikawa, Toshihiro Tanaka, Yutaka Shinagawa, Yoshiki Kawajiri, 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
  • Publication number: 20020008992
    Abstract: The present invention proposes a non-volatile semiconductor storage, comprising a plurality of main bit lines, a plurality of sub bit lines connected to the main bit lines, and a plurality of memory cell arrays, each including a plurality of non-volatile semiconductor memory cells disposed like an array. Each of those memory cells has a source terminal, a drain terminal, and a control gate, and each source-drain path is connected to a sub bit line. Between a main bit line and a sub bit line connected to the main bit line is disposed the source-drain path of a first transistor, and the source-drain path of a second transistor is connected to the sub bit line.
    Type: Application
    Filed: September 14, 2001
    Publication date: January 24, 2002
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Kazuyoshi Shiba, Kazufumi Suzukawa, Masamichi Fujito, Takayuki Oshima, Sonoko Abe, Kiyoshi Matsubara
  • Patent number: 6307780
    Abstract: The present invention proposes a non-volatile semiconductor storage, comprising a plurality of main bit lines, a plurality of sub bit lines connected to the main bit lines, and a plurality of memory cell arrays, each including a plurality of non-volatile semiconductor memory cells disposed like an array. Each of those memory cells has a source terminal, a drain terminal, and a control gate, and each source-drain path is connected to a sub bit line. Between a main bit line and a sub bit line connected to the main bit line is disposed the source-drain path of a first transistor, and the source-drain path of a second transistor is connected to the sub bit line.
    Type: Grant
    Filed: July 27, 2000
    Date of Patent: October 23, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Toshihiro Tanaka, Yutaka Shinagawa, Kazuyoshi Shiba, Kazufumi Suzukawa, Masamichi Fujito, Takayuki Oshima, Sonoko Abe, Kiyoshi Matsubara