Patents by Inventor Masahito Isoda

Masahito Isoda 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: 8514638
    Abstract: In a semiconductor device and a write control circuit, a voltage detection unit detects a write voltage supplied to a storage element (electrical fuse element) in which only single writing is electrically performed and, when the write voltage is equal to or more than a predetermined threshold voltage, allows the write control unit to stop writing to the electrical fuse element regardless of the write signal. The above processing permits the write control circuit to suppress false writing caused by the fact that abnormality occurs in a write voltage and it becomes an overvoltage.
    Type: Grant
    Filed: December 11, 2011
    Date of Patent: August 20, 2013
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Tsuyoshi Koyashiki, Jun Nagayama, Masahito Isoda, Tomoharu Awaya
  • Publication number: 20120213014
    Abstract: In a semiconductor device and a write control circuit, a voltage detection unit detects a write voltage supplied to a storage element (electrical fuse element) in which only single writing is electrically performed and, when the write voltage is equal to or more than a predetermined threshold voltage, allows the write control unit to stop writing to the electrical fuse element regardless of the write signal. The above processing permits the write control circuit to suppress false writing caused by the fact that abnormality occurs in a write voltage and it becomes an overvoltage.
    Type: Application
    Filed: December 11, 2011
    Publication date: August 23, 2012
    Applicant: FUJITSU SEMICONDUCTOR LIMITED
    Inventors: Tsuyoshi KOYASHIKI, Jun Nagayama, Masahito Isoda, Tomoharu Awaya
  • Patent number: 6833739
    Abstract: An input buffer circuit includes a differential amplifier that receives a input signal and its complement and generates an amplified signal corresponding to the voltage difference between the input signal and its complement. A transfer circuit receives the input signal and generates a transfer signal having the same logical value as the input signal. A control circuit connected to the differential amplifier and the transfer circuit selects one of the amplified signal and the transfer signal for output by enabling either the differential circuit or the transfer circuit.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: December 21, 2004
    Assignee: Fujitsu Limited
    Inventor: Masahito Isoda
  • Patent number: 6389381
    Abstract: A method and apparatus for calculating circuit delay times efficiently arranges and stores data to reduce system memory requirements, which allows computers without large storage devices, such as conventional personal computers with limited hard disk space, to be used for testing preliminary device designs, Delay time ratio coefficient values representing a ratio of a delay time determined by values of dependency factors having a large correlation with one another to a predetermined reference delay time of a circuit element are stored in a coefficient table. The dependency factors include process condition, in use or operational temperature, and first and second operational supply voltages.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: May 14, 2002
    Assignee: Fujitsu Limited
    Inventors: Masahito Isoda, Takashi Yoneda, Rieko Suzuki
  • Publication number: 20010011911
    Abstract: An input buffer circuit includes a differential amplifier that receives a input signal and its complement and generates an amplified signal corresponding to the voltage difference between the input signal and its complement. A transfer circuit receives the input signal and generates a transfer signal having the same logical value as the input signal. A control circuit connected to the differential amplifier and the transfer circuit selects one of the amplified signal and the transfer signal for output by enabling either the differential circuit or the transfer circuit.
    Type: Application
    Filed: March 20, 2001
    Publication date: August 9, 2001
    Applicant: FUJITSU LIMITED
    Inventor: Masahito Isoda
  • Patent number: 6247162
    Abstract: A method and apparatus for generating external power wiring layout data for a semiconductor integrated circuit device determines an optimum layout without performing time consuming circuit simulation. An external power wiring supplies power to each of the functional blocks of the device. Design information is used to calculate a current consumption ratio for each power supply terminal of each functional block. Then, the current consumption for each power supply terminal is calculated using the calculated current consumption ratios. An external power wiring network is generated based on the calculated current consumption for each terminal. The generated external power wiring network is then analyzed and voltage and current values for each part of the network are calculated. Using the calculated voltage and current values, the wires are then optimally sized.
    Type: Grant
    Filed: December 29, 1998
    Date of Patent: June 12, 2001
    Assignee: Fujitsu Limited
    Inventors: Eiji Fujine, Takanori Nawa, Hiroshi Yuyama, Masahito Isoda