Patents by Inventor Hidehiro Shiga

Hidehiro Shiga 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: 20060023484
    Abstract: A plurality of ferroelectric memory cells is arrayed. One terminal of each memory cells arrayed in the same column is connected in common to a first bit line. A gate of a transistor of memory cells arrayed in the same row is connected in common to a word line. The other terminal of each of memory cells arrayed in the same column or the same row is connected in common to a cell plate line. A second bit line is connected with a reference voltage supply circuit. The first and second bit lines are connected with a data read circuit. The data read circuit includes a sense amplifier and a current mirror circuit having a pair of current input node connected to the first and second bit lines, and carrying the same current flowing through one of the first and second bit line to the other bit line.
    Type: Application
    Filed: February 1, 2005
    Publication date: February 2, 2006
    Inventors: Hidehiro Shiga, Shinichiro Shiratake, Daisaburo Takashima
  • Publication number: 20050275450
    Abstract: A booster circuit includes a first booster unit having a first output terminal from which a boosted voltage is output. The first output terminal is connected to an external output terminal. A second booster unit has a second output terminal from which a boosted voltage is output. The second output terminal is connected to the external output terminal. A control circuit outputs a first control signal used to control the operation of the first booster unit and a second control signal used to control the operation of the second booster unit. Further, the control circuit controls the first and second control signals so that a transition between the operative state and the non-operative state of the first booster unit and a transition between the operative state and the non-operative state of the second booster unit will be made at different timings according to output voltage of the external output terminal.
    Type: Application
    Filed: August 24, 2004
    Publication date: December 15, 2005
    Inventors: Hidehiro Shiga, Shinichiro Shiratake, Daisaburo Takashima
  • Publication number: 20050243599
    Abstract: A semiconductor memory device includes a cell block composed of several series-connected units having a ferroelectric capacitor and a cell transistor parallel-connected to the ferroelectric capacitor and a select transistor connected to an end of the cell block. Mutually separated first impurity diffusion layers are formed on the surface of the semiconductor substrate along a first direction, and have a first area. A second impurity diffusion layer is formed on the surface of the semiconductor substrate separated from the end first impurity diffusion layer, and has a second area. A first gate electrode is provided on the semiconductor substrate between the first impurity diffusion layers along a second direction. A second gate electrode is provided on the semiconductor substrate between the end first impurity diffusion layer and the second impurity diffusion layer along a second direction. A contact electrically connects a bit line and the second impurity diffusion layer.
    Type: Application
    Filed: July 23, 2003
    Publication date: November 3, 2005
    Inventors: Hidehiro Shiga, Shinichiro Shiratake, Daisaburo Takashima