Patents by Inventor Tatsumi Yamauchi

Tatsumi Yamauchi 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: 5619151
    Abstract: A semiconductor memory device which includes at least one of (1) an input buffer circuit which generates internal address signals in response to an incoming address; (2) a decoder circuit formed of plural logic gates each of which is composed of the combination of MOS and bipolar circuitry; (3) a sense amplifier circuit including a multiemitter transistor; (4) a signal or address transition detector circuit which includes input circuits each receiving, for example, an address signal of a voltage amplitude and outputting a current amplitude signal in response to a change in level of the address signal, and a detector circuit connected thereto which has a cascode amplifier arranged such that it receives current amplitude signals at an input thereof and in which the cascode amplifier input is maintained at a substantially constant voltage, in which the detection circuit detects a transition of one or more of the current amplitude signals and, in response thereto, generates an ATD signal of a voltage amplitude; a
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: April 8, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Akioka, Masahiro Iwamura, Atsushi Hiraishi, Yuji Yokoyama, Nozomu Matsuzaki, Tatsumi Yamauchi, Yutaka Kobayashi, Nobuyuki Gotou, Akira ide, Masahiro Yamamura, Hideaki Uchida
  • Patent number: 5612640
    Abstract: A semiconductor integrated circuit device is equipped with a series of data handling stages, at least one of which includes a plurality of functional blocks arranged in parallel, a connecting means for connecting the functional blocks to functional blocks in a subsequent data handling stage, and a detection means for detecting data flow along a first connection in the connecting means. The detection means is included within a control means which controls data flow through at least one other connection in the connecting means based on the detection of data flow through the first connection in the connecting means.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: March 18, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Fumio Murabayashi, Tatsumi Yamauchi, Yutaka Kobayashi
  • Patent number: 5590361
    Abstract: An extra large number-of-input complex logic circuit, employed inside a microprocessor for performing a large number of controls and arithmetic operations, is constructed utilizing N(N.gtoreq.2) number of a unit logic circuit each comprising M(M.gtoreq.1) input CMOS logic circuits and one bipolar transistor, whereby respective outputs are integrated to produce one output in response to M.times.N number input signals to provide a high speed, high density integration and low power consumption microprocessor.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: December 31, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Iwamura, Tatsumi Yamauchi, Shigeya Tanaka, Kazutaka Mori
  • Patent number: 5544125
    Abstract: An arrangement which is particularly effective for decoders in semiconductor memory circuits which use, for example, common NMOS to receive one input for a plurality of logic decoder gates is provided includes a plurality of logic gates each having a first input terminal for respectively receiving first input signals, and each being coupled to a common node. In one embodiment, first and second switching elements are also coupled to the common node. The first and second switching elements are both coupled to a second input terminal for receiving a second input signal which is common to the plurality of logic gates, and both operate complementary to one another in response to the second input signal. An improved read/write arrangement is also provided for such semiconductor memory circuits which includes circuitry to prevent connection of a common read line to the data lines during the writing operation. This enhances the writing speed by removing the load of the common read line during writing.
    Type: Grant
    Filed: February 6, 1995
    Date of Patent: August 6, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Yuji Yokoyama, Takashi Akioka, Masahiro Iwamura, Atsushi Hiraishi, Yutaka Kobayashi, Tatsumi Yamauchi, Shigeru Takahashi, Nobuyuki Gotou, Akira Ide
  • Patent number: 5502820
    Abstract: An improved buffer circuit arrangement is provided which is particularly useful for semiconductor integrated circuit semiconductor memories and microprocessors. The buffer circuit is capable of switching large loads in various types of LSIs, and features a low noise and high speed circuit operation. This is accomplished by a parallel connection of output transistors in an output buffer circuit, and by differentiating the starting time of operation between the output transistors connected in parallel without using a delay circuit. For example, differentiating the starting times can be achieved by either providing the transistors with different characteristics from one another or the driving circuits with different characteristics from one another. Another aspect of the circuit is the provision of a two-level preset arrangement which presets the output node of the circuit to predetermined values before the input signals are applied.
    Type: Grant
    Filed: February 8, 1995
    Date of Patent: March 26, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Hiraishi, Takashi Akioka, Yutaka Kobayashi, Yuji Yokoyama, Masahiro Iwamura, Tatsumi Yamauchi, Shigeru Takahashi, Hideaki Uchida, Akira Ide
  • Patent number: 5398318
    Abstract: An improved buffer circuit arrangement is provided which is particularly useful for semiconductor integrated circuit semiconductor memories and microprocessors. The buffer circuit is capable of switching large loads in various types of LSIs, and features a low noise and high speed circuit operation. This is accomplished by a parallel connection of output transistors in an output buffer circuit, and by differentiating the starting time of operation between the output transistors connected in parallel without using a delay circuit. For example, differentiating the starting times can be achieved by either providing the transistors with different characteristics from one another or the driving circuits with different characteristics from one another. Another aspect of the circuit is the provision of a two-level preset arrangement which presets the output node of the circuit to predetermined values before the input signals are applied.
    Type: Grant
    Filed: November 2, 1990
    Date of Patent: March 14, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Hiraishi, Takashi Akioka, Yutaka Kobayashi, Yuji Yokoyama, Masahiro Iwamura, Tatsumi Yamauchi, Shigeru Takahashi, Hideaki Uchida, Akira Ide
  • Patent number: 5387827
    Abstract: A semiconductor integrated logic circuit is provided which includes a plurality of logic gates each having a first input terminal for respectively receiving first input signals, wherein each of the logic gates is coupled to a common node. In one embodiment, first and second switching elements are also coupled to the common node. The first and second switching elements are both coupled to a second input terminal for receiving a second input signal which is common to the plurality of logic gates, and both operate complementary to one another in response to the second input signal. This arrangement is particularly effective for decoders in semiconductor memory circuits which use a common NMOS to receive one input for a plurality of logic decoder gates. An improved read/write arrangement is also provided for semiconductor memory circuits which includes circuitry to prevent connection of a common read line to the data lines during the writing operation.
    Type: Grant
    Filed: January 22, 1991
    Date of Patent: February 7, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Yuji Yokoyama, Takashi Akioka, Masahiro Iwamura, Atsushi Hiraishi, Yutaka Kobayashi, Tatsumi Yamauchi, Shigeru Takahashi, Nobuyuki Gotou, Akira Ide
  • Patent number: 5345421
    Abstract: A wide-bit output semiconductor storage device of high speed and low noise is provided in which output circuits are grouped into two groups and the two output circuit groups are so controlled as to be switched in directions of levels which are opposite to each other.
    Type: Grant
    Filed: June 29, 1992
    Date of Patent: September 6, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Iwamura, Tatsumi Yamauchi, Makoto Saeki, Hideaki Uchida
  • Patent number: 5339448
    Abstract: A microprocessor according to the present invention comprises a sub-read bus, to which output terminals of registers of a register file of the microprocessor are coupled. The sub-read bus is in turn coupled to a main read bus of the microprocessor through a bus output circuit. Upon occurrence of a read access to any of the registers, the bus output circuit couples the sub-read bus with the main read bus, whereby data read out from the registers to the sub-read bus are transmitted to the main read bus, and under no existence of the read access, the bus output circuit interrupts the data transmission from the sub-read bus to the main read bus. With this, a load capacitance of the read bus is reduced. As a result, a time for making access to the read bus is much improved.
    Type: Grant
    Filed: January 22, 1993
    Date of Patent: August 16, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Shigeya Tanaka, Masahiro Iwamura, Tatsumi Yamauchi, Tatsuo Nojiri, Hisashi Tada, Tetsuo Nakano
  • Patent number: 5285414
    Abstract: A semiconductor memory comprises a write driver which is provided to correspond to respective data line and by which data lines connected with a memory cell through the control of a word line are driven in a write operation. The write driver includes MOSFETs of first group and MOSFETs of second group. In a case where a write enable signal does not designate the write operation, the MOSFETs of the first group are normally in ON states to pull up the data lines. Besides, in a case where the write enable signal designates the write operation, each of them operates in accordance with the value of input data, to maintain the ON states and pull up the corresponding data line in case of driving the data line to a "high" level and to fall into OFF states in case of driving the data line to a "low" level. On the other hand, the MOSFETs of the second group are normally in OFF states.
    Type: Grant
    Filed: September 26, 1991
    Date of Patent: February 8, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Tatsumi Yamauchi, Masahiro Iwamura, Kazutaka Mori
  • Patent number: 5153452
    Abstract: There are provided a bipolar-MOS IC device smaller than half-micron scale, and a combination of such IC device and external circuits. The IC device has an internal voltage generating circuit for generating an internal power source by using an external power source, the voltage of the internal power source being lower than that of the external power source. The internal voltage generating circuit includes an NPN transistor formed in an N-type region or N-type island within a P-type semiconductor substrate of the IC device, and a PMOS transistor formed in the N-type island. The collector of the NPN transistor and the source of the PMOS transistor are used as external power source terminals. The drain of the PMOS transistor is connected to the base of the NPN transistor. The gate is used as a control signal terminal. The emitter of the NPN transistor is used as an internal power source output terminal.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: October 6, 1992
    Assignee: Hitachi Ltd.
    Inventors: Masahiro Iwamura, Shigeya Tanaka, Tatsumi Yamauchi, Ikuro Masuda, Tetsuo Nakano
  • Patent number: 5091883
    Abstract: An input buffer for processing an external signal is provided in one of passways, which is the most closest to a line for equally dividing the whole of a plurality of memory cell blocks longitudinally or laterally into two sections, the passway interposing between the adjacent memory cell blocks of the plurality of memory cell blocks to which a processed signal of the input buffer is transmitted, whereby the length of the signal pass from the input buffer to each memory cell of the memory cell blocks can be shortened. Therefore, since the memory cell or a logic element existing between the input buffer and the memory cell is operated by a pulse of little distortion without delay of time, a access time can be reduced and a processing speed of a microprocessor can be increased. Further, a degree of freedom in designing a system of a memory or the microprocessor is further improved.
    Type: Grant
    Filed: July 13, 1990
    Date of Patent: February 25, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Nozomu Matsuzaki, Takashi Akioka, Masahiro Iwamura, Atushi Hiraishi, Tatsumi Yamauchi, Yuji Yokoyama, Yutaka Kobayashi, Hideaki Uchida
  • Patent number: 4678943
    Abstract: A switching circuit comprises a pre-stage circuit coupled to receive an input signal and an output stage, wherein an output signal having a phase opposite to that of a signal of an input terminal IN can be obtained from an output terminal OUT of the output stage. The pre-stage circuit includes a p-channel MOSFET M1 and an n-channel MOSFET M2 that receive input signals at their gates. The output stage includes two NPN transistors Q1 and Q2 that are connected in series. The drain output of the p-channel MOSFET M1 is applied to the base of one of the transistors of the output stage, and the source output of the n-channel MOSFET M2 is applied to the base of the other of the transistors of the output stage. A third MOSFET M3 is coupled between a power supply and the p-channel MOSFET M1 and the n-channel MOSFET M2. When the MOSFET M3 is rendered non-conductive by a control signal EN, both MOSFETs M1 and M2 and both NPN transistors Q1 and Q2 become non-conductive irrespective of the signal of the input terminal IN.
    Type: Grant
    Filed: February 22, 1985
    Date of Patent: July 7, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Akira Uragami, Yukio Suzuki, Shinji Kadono, Masahiro Iwamura, Ikuro Masuda, Tatsumi Yamauchi