Patents by Inventor Tadahiro Kuroda

Tadahiro Kuroda 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: 5933029
    Abstract: To minimize the power consumption, the disclosed semiconductor integrated circuit device, comprises; a bias circuit for generating a predetermined voltage fixed between a first supply voltage and a second supply voltage; a driver circuit for receiving an inversion input signal and a non-inversion input signal each vibrating between the first and second supply voltages, for converting the received input signals into a signal vibrating between an output voltage of the bias circuit and the first supply voltage, and for driving a transfer path by the converted signal; a voltage divider circuit for dividing an output voltage of the bias circuit; and a receiver circuit for detecting the signal for driving the transfer path by use of an output of the voltage divider circuit as a reference voltage, and for converting the detected signal into a signal vibrating between the first/supply voltage and the second supply voltage.
    Type: Grant
    Filed: April 28, 1997
    Date of Patent: August 3, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadahiro Kuroda, Takayasu Sakurai
  • Patent number: 5929693
    Abstract: The semiconductor integrated circuit device can control the threshold voltage of MOSFETs at a low value while keeping the variation thereof at a small level in operation mode, but switches the threshold voltage thereof from the low value to a high value in standby mode. The semiconductor integrated circuit device comprises: a detecting circuit for detecting a physical quantity (e.g., substrate bias) of a semiconductor substrate and for outputting n-units (n.gtoreq.
    Type: Grant
    Filed: January 28, 1997
    Date of Patent: July 27, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tadahiro Kuroda
  • Patent number: 5834967
    Abstract: A semiconductor integrated circuit device includes a leak detection circuit which can be realized by small pattern area provides voltage Vb through two transistors M1n and M2n, which are caused to be operative in the sub-threshold area without use of a resistor at the gate of a leak current detection transistor MLn. The leak current detection magnification does not become dependent upon power supply voltage and temperature. Thus, detection of the leakage current can be precisely carried out.
    Type: Grant
    Filed: September 3, 1996
    Date of Patent: November 10, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadahiro Kuroda, Tetsuya Fujita
  • Patent number: 5764086
    Abstract: The comparator circuit comprises a first comparator circuit having a differential input stage composed of P-channel FETs; a second comparator circuit having a differential input stage composed of N-channel FETs; pull-up and pull-down resistances connected to the output terminals of the two comparator circuits, respectively; at least one skew adjusting circuit having a delay circuit and a selector; and a logical gate for obtaining the two output signals of the two comparator circuits. Since the two differential input signals can be received by the two comparator circuits and according to the potentials of the two differential input signals, even if the supply potential is low, the comparator circuit can compare the two differential input signals in a wide potential range from the ground potential and the supply potential, so that it is possible to provide a high speed interface circuit which can satisfy the LVDS standard at a low supply potential.
    Type: Grant
    Filed: September 4, 1996
    Date of Patent: June 9, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tetsu Nagamatsu, Tadahiro Kuroda
  • Patent number: 5742183
    Abstract: A level shift semiconductor device converts a signal level into another level between circuits connected to each other having different supply voltages. An input signal is supplied to the source of a first MOS transistor of a first-conductivity type (NMOS). The drain of the 1st NMOS transistor is connected to the input terminal of an inverter. An output signal is outputted via the output terminal of the inverter. The drain and gate of a first MOS transistor of a second-conductivity type (PMOS) are connected to the input and output terminals of the inverter, respectively. The gate and source of a second NMOS transistor are connected to the output terminal of the inverter and the gate of the 1st NMOS transistor, respectively. The gate and source of a second PMOS transistor are connected to the gate and source of the 2nd NMOS transistor. A first supply voltage is supplied to the drain of the 2nd PMOS transistor.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: April 21, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tadahiro Kuroda
  • Patent number: 5684416
    Abstract: A semiconductor integrated circuit device has a differential logic circuit formed by multi-stage series-gating logic circuits each composed of bipolar transistors whose emitters are connected in common and level shift circuits each for shifting a level of an input signal that is inputted from the outside in correspondence to one of the stage logic circuits of the differential logic circuit, and for supplying the level-shifted input signal to the base of one of the bipolar transistors of the corresponding logic circuit. In particular, a potential difference between the level-shifted signals inputted to the bases of the bipolar transistors of each of the stage logic circuits is determined, as a level shift rate, to be lower than a built-in potential between the base and emitter of each of the bipolar transistors thereof. The semiconductor integrated circuit device is operative on a lower supply voltage, without significantly degrading the functions and performance thereof.
    Type: Grant
    Filed: April 18, 1995
    Date of Patent: November 4, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tadahiro Kuroda
  • Patent number: 5627477
    Abstract: The semiconductor device includes a circuit, such as, an ECL circuit for comparing input signals with a reference potential determined as a circuit threshold value and outputting an output signal according to the comparison result. The semiconductor device further includes a switching circuit for switching the reference potential level between ordinary operation and burn-in operation of the ECL circuit. The time required for the burn-in operation can be reduced markedly.
    Type: Grant
    Filed: May 22, 1996
    Date of Patent: May 6, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadahiro Kuroda, Makoto Noda
  • Patent number: 5614843
    Abstract: A level conversion circuit is provided which can obtain a stable output voltage, with keeping low power consumption and a high speed operation, if manufacturing processes and operational conditions of the LSI'S are varied.
    Type: Grant
    Filed: January 5, 1996
    Date of Patent: March 25, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinji Mita, Tadahiro Kuroda
  • Patent number: 5381057
    Abstract: The present invention relates to a modified emitter coupled logic circuit which includes a differential logic stage and an emitter-follower output stage. An active pull-down circuit and a constant voltage source are included in the output stage of this circuit to allow the output of the circuit to switch from a high level to a low level at approximately the same speed as the output can switch from a low level to a high level. A particular embodiment of the present invention provides a constant voltage source comprising an operational amplifier, a reference potential generating circuit and a constant voltage signal adjusting circuit.
    Type: Grant
    Filed: May 3, 1993
    Date of Patent: January 10, 1995
    Assignees: Kabushiki Kaisha Toshiba, Synergy Semiconductor Corporation
    Inventors: Tadahiro Kuroda, David A. Gray
  • Patent number: 5369318
    Abstract: The output terminal of an ECL circuit is directly connected to the input terminal of a CMOS output circuit. The CMOS output circuit has a transistor which sets the threshold voltage of the CMOS output circuit nearly midway between ECL logic levels. A first reference voltage generating circuit has substantially the same arrangement as the CMOS output circuit and outputs a potential midway between CMOS logic levels as a first reference voltage Vref1. The first reference voltage Vref1 is made variable. A second reference voltage generating circuit has substantially the same arrangement as the ECL circuit and outputs a potential which is midway between the ECL logic levels as a second reference voltage Vref2. A comparator makes a comparison between the first and second reference voltages Vref1 and Vref2 and controls the first reference voltage generating circuit and the CMOS output circuit so that the first and second reference voltages Vref1 and Vref2 may become equal to each other.
    Type: Grant
    Filed: June 23, 1993
    Date of Patent: November 29, 1994
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadahiro Kuroda, Shinji Fujii, Masahiro Kimura, Kazuhiko Kasai
  • Patent number: 5268872
    Abstract: The gate of a first P-channel transistor of a first comparator is supplied with an input signal, and the gate of a second P-channel transistor of the first comparator is supplied with a reference voltage. An output terminal of the first comparator is connected to an output circuit and the gates of first and second P-channel transistors of a second comparator are supplied with the reference voltage. The second comparator outputs a voltage equal to a stand-by time output voltage of the first comparator and the output voltage from the second comparator is supplied to the non-inversion input terminal of a third comparator which is connected to a voltage generating circuit. The voltage generating circuit has substantially the same dimension ratio as the output circuit and generates a voltage equal to the threshold voltage of the output circuit.
    Type: Grant
    Filed: September 27, 1991
    Date of Patent: December 7, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinji Fujii, Tadahiro Kuroda, Kenji Matsuo, Ayako Hirata, Kazuhiko Kasai, Toshiyuki Fukunaga, Masahiro Kimura
  • Patent number: 5227865
    Abstract: A sense amplifier of this invention has a main characteristic feature in that it has low power consumption in an input waiting state, and can perform a highspeed sensing operation. The sense amplifier includes an output transistor, a constant current source connected between the base of the transistor and a first power source, a MOS transistor, having a source-drain path connected between the base of the transistor and a second power source, for receiving most of a current from the constant current source, and a load resistor for the transistor. The base potential of the output transistor in the input waiting state is set to be a value corresponding to a state immediately before or after the transistor is turned on.
    Type: Grant
    Filed: December 24, 1991
    Date of Patent: July 13, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Moriizumi, Tadahiro Kuroda, Kazuhiko Kasai, Toshiyuki Fukunaga
  • Patent number: 5187555
    Abstract: Transistor elements which are not initially wired are previously arranged in no-cell regions created in part of cell array regions in a standard cell layout according to the layout design. When the circuit is changed in the standard cell layout, a desired circuit is formed in the no-cell region by using the transistor elements which are not initially wired. After the circuit change, an unnecessary circuit is made inoperative. Wiring inhibition regions for inhibiting the normal wiring in the standard cell layout are provided in order to extend the input and output terminals of the desired circuit from the no-cell region to the wiring region.
    Type: Grant
    Filed: September 26, 1991
    Date of Patent: February 16, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadahiro Kuroda, Hiroaki Suzuki