Patents by Inventor Terufumi Ishida

Terufumi Ishida 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: 7360049
    Abstract: In a nonvolatile semiconductor memory device according to the present invention, a password protection function is enabled or disabled based on a first specified value M and a second state specified value P such that when both of the first specified value M and the second state specified value P are in a set state, the password protection function is enabled and when at least the second specified value P is in a reset state, the password protection function is disabled, and the first state specified value M maintains a previous state and the second state specified value P follows the state of the first state specified value M in response to a reset operation, and the cancel operation to shift the second state specified value P to the reset state can be performed only when the password is inputted correctly.
    Type: Grant
    Filed: April 20, 2006
    Date of Patent: April 15, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Terufumi Ishida
  • Publication number: 20060242425
    Abstract: In a nonvolatile semiconductor memory device according to the present invention, a password protection function is enabled or disabled based on a first specified value M and a second state specified value P such that when both of the first specified value M and the second state specified value P are in a set state, the password protection function is enabled and when at least the second specified value P is in a reset state, the password protection function is disabled, and the first state specified value M maintains a previous state and the second state specified value P follows the state of the first state specified value M in response to a reset operation, and the cancel operation to shift the second state specified value P to the reset state can be performed only when the password is inputted correctly.
    Type: Application
    Filed: April 20, 2006
    Publication date: October 26, 2006
    Inventor: Terufumi Ishida
  • Patent number: 6947342
    Abstract: A semiconductor storage device includes: a memory cell array including a plurality of memory cells which are connected to a plurality of pairs of complementary bit lines; an internal voltage decreasing section for generating a predetermined voltage lower than a power supply voltage; and an equalizing section for performing an equalizing operation to charge the pairs of complementary bit lines to a predetermined equal potential, wherein the internal voltage decreasing section is formed by first and second internal voltage decreasing sections, the equalizing section is formed by a first equalizing section, which is provided at one side of the memory cell array, and a second equalizing section, which is provided at the other side of the memory cell array, the first and second internal voltage decreasing sections supply an electric power to the first and second equalizing sections, respectively.
    Type: Grant
    Filed: June 25, 2002
    Date of Patent: September 20, 2005
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Terufumi Ishida, Takahiro Nakai
  • Patent number: 6804157
    Abstract: A charging circuit includes a charging driving circuit, a time constant circuit, a control circuit, a voltage detection circuit, and a delay and inversion circuit. The charging driving circuit starts a charging operation in accordance with a delay signal output from the delay and inversion circuit, and terminates the charging operation in accordance with a detection signal output from the voltage detection circuit.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: October 12, 2004
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Terufumi Ishida
  • Publication number: 20040160260
    Abstract: A charging circuit includes a charging driving circuit, a time constant circuit, a control circuit, a voltage detection circuit, and a delay and inversion circuit. The charging driving circuit starts a charging operation in accordance with a delay signal output from the delay and inversion circuit, and terminates the charging operation in accordance with a detection signal output from the voltage detection circuit.
    Type: Application
    Filed: February 4, 2004
    Publication date: August 19, 2004
    Applicant: SHARP KABUSHIKI KAISHA
    Inventor: Terufumi Ishida
  • Patent number: 6717872
    Abstract: A charging circuit includes a charging driving circuit, a time constant circuit, a control circuit, a voltage detection circuit, and a delay and inversion circuit. The charging driving circuit starts a charging operation in accordance with a delay signal output from the delay and inversion circuit, and terminates the charging operation in accordance with a detection signal output from the voltage detection circuit.
    Type: Grant
    Filed: June 24, 2002
    Date of Patent: April 6, 2004
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Terufumi Ishida
  • Publication number: 20030021168
    Abstract: A semiconductor storage device includes: a memory cell array including a plurality of memory cells which are connected to a plurality of pairs of complementary bit lines; an internal voltage decreasing section for generating a predetermined voltage lower than a power supply voltage; and an equalizing section for performing an equalizing operation to charge the pairs of complementary bit lines to a predetermined equal potential, wherein the internal voltage decreasing section is formed by first and second internal voltage decreasing sections, the equalizing section is formed by a first equalizing section, which is provided at one side of the memory cell array, and a second equalizing section, which is provided at the other side of the memory cell array, the first and second internal voltage decreasing sections supply an electric power to the first and second equalizing sections, respectively.
    Type: Application
    Filed: June 25, 2002
    Publication date: January 30, 2003
    Inventors: Terufumi Ishida, Takahiro Nakai
  • Publication number: 20030002372
    Abstract: A charging circuit includes a charging driving circuit, a time constant circuit, a control circuit, a voltage detection circuit, and a delay and inversion circuit. The charging driving circuit starts a charging operation in accordance with a delay signal output from the delay and inversion circuit, and terminates the charging operation in accordance with a detection signal output from the voltage detection circuit.
    Type: Application
    Filed: June 24, 2002
    Publication date: January 2, 2003
    Inventor: Terufumi Ishida