Patents by Inventor Naokatsu Moriyama

Naokatsu Moriyama 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).

  • System for monitoring a period of an operation clock signal of a CPU and stopping operations of the CPU when the period is out of a predetermined allowable range
    Patent number: 7080001
    Abstract: There is provided a technology for preventing disabling of function of a clock monitoring circuit by a hacker in a microcomputer for IC card provided with a clock monitoring circuit as a countermeasure for a hacker. In the microcomputer for IC card provided with the clock monitoring circuit, the clock monitoring circuit is given the function to perform the detecting operation twice during one cycle, namely at the timings of rise and fall of the clock.
    Type: Grant
    Filed: February 26, 2003
    Date of Patent: July 18, 2006
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Naokatsu Moriyama, Shigeru Shinohara
  • Data processing system
    Publication number: 20040117693
    Abstract: There is provided a technology for preventing disabling of function of a clock monitoring circuit by a hacker in a microcomputer for IC card provided with a clock monitoring circuit as a countermeasure for a hacker. In the microcomputer for IC card provided with the clock monitoring circuit, the clock monitoring circuit is given the function to perform the detecting operation twice during one cycle, namely at the timings of rise and fall of the clock.
    Type: Application
    Filed: February 26, 2003
    Publication date: June 17, 2004
    Applicants: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Naokatsu Moriyama, Shigeru Shinohara