Patents by Inventor Katsuhiko Kabashima

Katsuhiko Kabashima 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: 20060244019
    Abstract: A semiconductor device includes a semiconductor substrate having a source region and a drain region, a gate formed on the semiconductor substrate, a diode having a cathode region connected to the drain region, and a bit line connected to an anode region of the diode. The drain region and the cathode region are formed by a drain/cathode common region of an N-type semiconductor region.
    Type: Application
    Filed: January 26, 2006
    Publication date: November 2, 2006
    Inventors: Masao Sugizaki, Katsuhiko Kabashima, Toshiyuki Tanaka
  • Patent number: 4570088
    Abstract: A semiconductor device, provided with a buffer, which comprises a first transistor for pulling up the output terminal voltage, a second transistor for pulling down the output terminal voltage, and a charge-pumping circuit for maintaining the output terminal voltage at a level higher than the power source voltage by charge pumping when the output terminal voltage is at a high level. The semiconductor device further comprises a circuit for pulling down the output terminal voltage during the period from when power is supplied to when an input signal is supplied to the buffer.
    Type: Grant
    Filed: July 1, 1983
    Date of Patent: February 11, 1986
    Assignee: Fujitsu Limited
    Inventors: Shigeki Nozaki, Tomio Nakano, Katsuhiko Kabashima
  • Patent number: 4551822
    Abstract: A dynamic semiconductor memory device having a refresh-address generator, includes an initial resetting circuit for resetting the output signals of a refresh-address counter when the power supply is turned on, thereby eliminating the need for counter checking procedures prior to the examination of the refresh-address generator.
    Type: Grant
    Filed: December 7, 1982
    Date of Patent: November 5, 1985
    Assignee: Fujitsu Limited
    Inventors: Yoshihiro Takemae, Katsuhiko Kabashima
  • Patent number: 4550289
    Abstract: A semiconductor integrated circuit (IC) device includes therein a test circuit. The test circuit operates to distinguish the power source level during the testing or ground level occurring at an internal node located inside the semiconductor chip. The test circuit includes a series-connected MIS transistor and an MIS diode. The gate of the MIS transistor is connected to the internal node. The MIS diode is connected to an external input/output (I/O) pin. The level at the internal node, i.e., the power source level or the ground level, can be distinguished by a first voltage level or a second voltage level applied to the external I/O pin, whichever enables a current to be drawn from the external I/O pin.
    Type: Grant
    Filed: December 27, 1982
    Date of Patent: October 29, 1985
    Assignee: Fujitsu Limited
    Inventors: Katsuhiko Kabashima, Yoshihiro Takemae, Shigeki Nozaki, Tsuyoshi Ohira, Hatsuo Miyahara, Masakazu Kanai, Seiji Enomoto
  • Patent number: 4496850
    Abstract: A semiconductor circuit for driving a clock signal line comprising a first circuit for pulling up the potential of the clock signal line to the source voltage and a second circuit for pulling down the potential of the clock signal line to a lower voltage. A capacitor is connected to the clock signal line for receiving a potential push signal and pushing the potential of the clock signal line higher than the source voltage. The capacitor performs the function of capacitance only after the potential of the clock signal line is raised to the source voltage. The operational speed of a dynamic memory device associated with the semiconductor device is then enhanced.
    Type: Grant
    Filed: February 10, 1982
    Date of Patent: January 29, 1985
    Assignee: Fujitsu Limited
    Inventors: Yoshihiro Takemae, Shigeki Nozaki, Katsuhiko Kabashima, Seiji Enomoto
  • Patent number: 4482825
    Abstract: In a semiconductor device having a signal line on which a voltage higher than the voltage supply is generated, a conductive layer following the potential variance of the voltage supply is positioned under an insulating film directly below the signal line in order to make the level of the signal line follow the potential variance of the voltage supply.
    Type: Grant
    Filed: December 2, 1981
    Date of Patent: November 13, 1984
    Assignee: Fujitsu Limited
    Inventors: Shigeki Nozaki, Yoshihiro Takemae, Katsuhiko Kabashima, Seiji Enomoto
  • Patent number: 4458337
    Abstract: A buffer circuit comprises a flip-flop which is receives an external input via a first input circuit and a reference voltage via a second input circuit. Internal complementary outputs are then produced via an output circuit. The flip-flop cooperates with at least one level setting device by way of a second input circuit. The level setting device functions to produce a voltage level to deactivate the second input circuit during activation of the flip-flop.
    Type: Grant
    Filed: March 3, 1982
    Date of Patent: July 3, 1984
    Assignee: Fujitsu Limited
    Inventors: Yoshihiro Takemae, Shigeki Nozaki, Tsutomu Mezawa, Katsuhiko Kabashima, Seiji Enomoto
  • Patent number: 4451908
    Abstract: An address buffer for a dynamic memory includes a flip-flop. The flip-flop is coupled at its one input/output terminal with both a first input circuit and a third input circuit connected in parallel with each other and at its other input/output terminal with a second input circuit. The second input circuit receives a reference voltage and is activated by an external address timing clock during a normal operation mode. The first input circuit is also activated by the external address timing clock, but receives an external address. The third input circuit receives an internal refresh address and is activated by an internal refresh address. The address buffer cooperates with a switcher which produces the internal refresh address timing clock and the external address timing clock, alternatively, by switching a basic timing clock generated by an address drive clock generator.
    Type: Grant
    Filed: March 3, 1982
    Date of Patent: May 29, 1984
    Assignee: Fujitsu Limited
    Inventors: Yoshihiro Takemae, Shigeki Nozaki, Katsuhiko Kabashima, Seiji Enomoto, Tsutomu Mezawa
  • Patent number: 4447745
    Abstract: A semiconductor circuit used as a buffer circuit having an input stage circuit for receiving an input clock signal and an inverted input clock signal, a bootstrap circuit including a transistor for receiving the output of the input stage circuit and for maintaining the gate voltage of the transistor at a high level during the standby period, and an output circuit, including a transistor which is switched on and off by the output of the bootstrap circuit, for generating an output clock signal; the semiconductor circuit further comprising a current leak circuit for maintaining, during the standby period, the voltage of a point in the semiconductor circuit which is charged during the standby period at the value corresponding to the voltage of the power source, whereby the delay of the output clock signal, caused of the fluctuation by the voltage of the power supply during the standby period, is improved and then the high speed access time in the dynamic memory is carried out.
    Type: Grant
    Filed: November 18, 1981
    Date of Patent: May 8, 1984
    Assignee: Fujitsu Limited
    Inventors: Yoshihiro Takemae, Seiji Enomoto, Shigeki Nozaki, Tsutomu Mezawa, Katsuhiko Kabashima
  • Patent number: 4417329
    Abstract: An active pull-up circuit for use in a sense amplifier or the like, comprises an enhancement type MIS transistor, a MIS capacitor controlled by a clock signal, and a depletion type MIS transistor controlled by another clock signal (.phi..sub.2 '). In this circuit, the two clock signals are bilevel signals having potentials which are the same as potentials of two power supplies.
    Type: Grant
    Filed: July 27, 1981
    Date of Patent: November 22, 1983
    Assignee: Fujitsu Limited
    Inventors: Tsutomu Mezawa, Katsuhiko Kabashima, Shigeki Nozaki, Yoshihiro Takemae
  • Patent number: 4336465
    Abstract: A reset circuit used for resetting, for example a memory device after a reading-out from a memory is effected, comprises fist and second reset transistors, for connecting first and second circuits to a common voltage source, and a short-circuit transistor, having a lower threshold voltage than the threshold voltage of said first and second reset transistors, for connecting said first and second circuits when said short circuit transistor receives the same input signal as supplied to said first and second reset transistors.
    Type: Grant
    Filed: July 27, 1979
    Date of Patent: June 22, 1982
    Assignee: Fujitsu Limited
    Inventors: Masao Nakano, Yoshihiro Takemae, Katsuhiko Kabashima
  • Patent number: 4291394
    Abstract: A semiconductor memory device having flip-flop circuits, in which first and second bit lines are connected to each of the flip-flop circuits as a sense amplifier, the potential of the second bit line being opposite to the potential of the first bit line, and the first and second data bus lines cross perpendicularly to the first and second bit lines, respectively, the first and second dummy lines are arranged in parallel with the first and second data bus lines respectively, in order to prevent erroneous operation of an I/O amplifier connected to the first and second data bus lines.
    Type: Grant
    Filed: October 22, 1979
    Date of Patent: September 22, 1981
    Assignee: Fujitsu Limited
    Inventors: Masao Nakano, Tomio Nakano, Yoshihiro Takemae, Katsuhiko Kabashima
  • Patent number: 4156939
    Abstract: An integrated semiconductor memory device is formed on a semiconductor substrate of one conductivity type on which there are provided peripheral circuits consisting of a pluality of memory cells each containing a storage capacitor and an IG FET. The IG FET in each memory cell acts as a transfer gate which is disposed on a surface region having the same conductivity type as that of the substrate and higher impurity concentrations than that of the substrate. The transfer gate has a gate threshold value which is higher than that of the IG FET in the peripheral circuits and which is insensitive to a noise pulse supplied thereto, whereby the destruction of data by noise pulse can be effectively prevented.
    Type: Grant
    Filed: May 23, 1978
    Date of Patent: May 29, 1979
    Assignee: Fujitsu Limited
    Inventors: Yoshihiro Takemae, Takeo Tatematsu, Katsuhiko Kabashima, Tomio Nakano, Kiyoshi Miyasaka