Patents by Inventor Jumpei Maruyama

Jumpei Maruyama 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: 8339860
    Abstract: This invention offers a semiconductor memory device, with which a resolution to read-out data is not reduced even at the time of verify and a stable read-out operation is possible even when a power supply voltage is reduced. A read-out circuit is provided with a current-voltage conversion circuit, that converts a cell current into a data voltage, and a sense amplifier that compares the data voltage with a reference voltage. The current-voltage conversion circuit is formed to include a variable load resistor that is connected to the memory cell through a bit line. The variable load resistor is formed to include P channel type MOS transistors that make load resistors and P channel type MOS transistors that constitute a switching circuit.
    Type: Grant
    Filed: January 21, 2011
    Date of Patent: December 25, 2012
    Assignees: SANYO Electric Co., Ltd., SANYO Semiconductor Co., Ltd.
    Inventors: Jumpei Maruyama, Sadao Yoshikawa
  • Publication number: 20110188316
    Abstract: This invention offers a semiconductor memory device, with which a resolution to read-out data is not reduced even at the time of verify and a stable read-out operation is possible even when a power supply voltage is reduced. A read-out circuit is provided with a current-voltage conversion circuit, that converts a cell current into a data voltage, and a sense amplifier that compares the data voltage with a reference voltage. The current-voltage conversion circuit is formed to include a variable load resistor that is connected to the memory cell through a bit line. The variable load resistor is formed to include P channel type MOS transistors that make load resistors and P channel type MOS transistors that constitute a switching circuit.
    Type: Application
    Filed: January 21, 2011
    Publication date: August 4, 2011
    Applicants: SANYO Electric Co., Ltd., SANYO Semiconductor Co., Ltd.
    Inventors: Jumpei MARUYAMA, Sadao Yoshikawa