Patents by Inventor Masahiro Iwamura

Masahiro Iwamura 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: 5512847
    Abstract: In an input level converter for TTL--CMOS level conversion (or other conversion to CMOS) for an internal logic block operating with CMOS levels, an output transistor for executing the charge or discharge of the output capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the input level converter can be lessened. Similarly, in an output level converter for CMOS--TTL level conversion (or other conversion from CMOS) for the internal logic block operating with the CMOS levels, an output transistor for executing the charge or discharge of the output load capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the output level converter can also be lessened.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: April 30, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Suzuki, Ikuro Masuda, Masahiro Iwamura, Shinji Kadono, Akira Uragami, Masayoshi Yoshimura, Toshiaki Matsubara
  • Patent number: 5506982
    Abstract: An information processing system having an original clock oscillator for delivering at least one original clock signal K defined as a first clock signal and a plurality of information processing units supplied with the original clock signal K, wherein each information processing unit comprises clock generating means for generating at least one second clock signal K.sub.1 which is phase-locked with the original clock signal K and which has a predetermined duty cycle and a logic device whose operation timing is controlled by the second clock signal K.sub.1, and the operation timing of an interface provided between at least one pair of logic devices is synchronously controlled by the clock signal K.sub.1.
    Type: Grant
    Filed: July 21, 1994
    Date of Patent: April 9, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Hotta, Kozaburo Kurita, Masahiro Iwamura, Hideo Maejima, Shigeya Tanaka, Tadaaki Bandoh, Yasuhiro Nakatsuka, Kazuo Kato, Sin-ichi Sinoda
  • 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: 5495183
    Abstract: In an input level converter for TTL--CMOS level conversion (or other conversion to CMOS) for an internal logic block operating with CMOS levels, an output transistor for executing the charge or discharge of the output capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the input level converter can be lessened. Similarly, in an output level converter for CMOS--TTL level conversion (or other conversion from CMOS) for the internal logic block operating with the CMOS levels, an output transistor for executing the charge or discharge of the output load capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the output level converter can also be lessened.
    Type: Grant
    Filed: May 12, 1995
    Date of Patent: February 27, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Suzuki, Ikuro Masuda, Masahiro Iwamura, Shinji Kadono, Akira Urragami, Masayoshi Yoshimura, Toshiaki Matsubara
  • Patent number: 5457790
    Abstract: In semiconductor integrated circuit device and microprocessor including at least one functional circuit block, the start of operation of the functional circuit block is detected prior to the start of operation, the functional circuit block for which the start of operation has been detected is activated prior to the start of operation and inactivated after the termination of operation.
    Type: Grant
    Filed: October 18, 1993
    Date of Patent: October 10, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Iwamura, Shigeya Tanaka, Hideo Maejima, Tetsuo Nakano
  • Patent number: 5412262
    Abstract: In a system wherein a plurality of semiconductor integrated circuit devices are coexistent and wherein a plurality of supply potential lines are laid, the main power sources of a TTL interface LSI and an ECL interface LSI are shared so as to reduce the number of supply potential lines. Besides, in a case where an LSI, for example, BiCMOS LSI to interface with both the TTL and ECL interface LSI's has a device withstand voltage of about 3 V, it is permitted to interface with both the LSI's across the supply voltage .vertline.5 V.vertline. of the main power source of the TTL interface LSI and the supply voltage .vertline.2 V.vertline. of the power source of the emitter follower portion of the ECL interface LSI because the supply voltages have a difference of 3 V.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: May 2, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Yoji Nishio, Fumio Murabayashi, Kozaburo Kurita, Masahiro Iwamura
  • 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: 5388249
    Abstract: An information processing system having an original clock oscillator for delivering at least one original clock signal K defined as a first clock signal and a plurality of information processing units supplied with the original clock signal K, wherein each information processing unit comprises clock generating means for generating at least one second clock signal K.sub.1 which is phase-locked with the original clock signal K and which has a predetermined duty cycle and a logic device whose operation timing is controlled by the second clock signal K.sub.1, and the operation timing of an interface provided between at least one pair of logic devices is synchronously controlled by the clock signal K.sub.1.
    Type: Grant
    Filed: April 22, 1992
    Date of Patent: February 7, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Hotta, Kozaburo Kurita, Masahiro Iwamura, Hideo Maejima, Shigeya Tanaka, Tadaaki Bandoh, Yasuhiro Nakatsuka, Kazuo Kato, Sin-ichi Sinoda
  • 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: 5378904
    Abstract: An LSI layout design method is for placing on a chip a plurality of different master cells, each of which has a plurality of signal wiring conductors not connected to internal elements, for example, transistors, resistors and so on for realizing a certain logic function.
    Type: Grant
    Filed: September 17, 1991
    Date of Patent: January 3, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Goro Suzuki, Masahiro Iwamura, Tetsuya Yamamoto, Yoshio Okamura
  • Patent number: 5378941
    Abstract: A high speed and low power consumption semiconductor integrated circuit device has a plurality of internal circuits each including circuit elements for performing a desired circuit operation, a plurality of input circuits for receiving external input signals and supplying the signals to the internal circuits and a plurality of output circuits for receiving the output signals from the internal circuits and supplying signals to an external circuit. Each of the internal circuits is primarily constructed by bipolar transistors and MOS transistors, and at least one of each of the input circuits and each of the output circuits is primarily constructed by bipolar transistors.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: January 3, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Yoji Nishio, Ikuro Masuda, Kazuo Kato, Shigeo Kuboki, Masahiro Iwamura
  • Patent number: 5362998
    Abstract: A composite circuit device of bipolar transistors and MOS transistors has a series connection of an NPN transistor for pull-up and a PNP transistor for pull-down. The composite circuit device has independent base drive circuits so provided that the base of the NPN transistor for pull-up is electrically isolated from the base of the PNP transistor for pull-down during the on-off switching operation. The composite circuit device is also provided with base precharge circuitry for pre-charging the base of the PNP transistor during the off operation state thereof. A composite circuit is also provided with circuitry for enhancing the turn-on switching speed of the pull-down PNP transistor. Additionally, a composite circuit of bipolar transistors and MOS transistors is constituted by a switch having a high input impedance and low on-resistance which can be applied as a component of an electronic circuit.
    Type: Grant
    Filed: February 7, 1994
    Date of Patent: November 8, 1994
    Assignee: Hitachi Ltd.
    Inventors: Masahiro Iwamura, Hideo Maejima, Atsuo Watanabe, Kazutaka Mori
  • Patent number: 5363332
    Abstract: A semiconductor integrated circuit device is arranged to have a plurality of logic circuit blocks, a data signal path for interconnecting logic circuit blocks and for providing a function of interfacing a current-driven signal. The logic circuit block on a signal output side includes an output circuit connected to the data signal path and a switching element formed of an NMOS transistor for controlling current flowing through the data signal path in response to an input signal applied to an input terminal of the output circuit. The logic circuit block on a signal input side includes an input circuit connected to the data signal path. The input circuit includes a bipolar transistor having an emitter connected to a constant current source, a collector forming an output terminal, and a base set at a fixed potential. The data signal path led from the output circuit is connected to the emitter of the bipolar transistor.
    Type: Grant
    Filed: March 30, 1992
    Date of Patent: November 8, 1994
    Assignee: Hitachi Ltd.
    Inventors: Fumio Murabayashi, Takashi Hotta, Masahiro Iwamura, Akiyoshi Osumi
  • 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: 5245224
    Abstract: In an input level converter for TTL-CMOS level conversion (or other conversion to CMOS) for an internal logic block operating with CMOS levels, an output transistor for executing the charge or discharge of the output capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the input level converter can be lessened. Similarly, in an output level converter for CMOS-TTL level conversion (or other conversion from CMOS) for the internal logic block operating with the CMOS levels, an output transistor for executing the charge or discharge of the output load capacitance thereof is formed of a bipolar transistor. Thus, the propagation delay times and their capacitance-dependencies of the output level converter can also be lessened.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: September 14, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Suzuki, Ikuro Masuda, Masahiro Iwamura, Shinji Kadono, Akira Uragami, Masayoshi Yoshimura, Toshiaki Matsubara
  • Patent number: 5239212
    Abstract: A high-speed operation, low-power consumption gate circuit structure comprises a combination of complementary field-effect-transistors and bipolar transistors and discharge means for discharging accumulated charges from these transistors when the field-effect-transistors and bipolar transistors are turned off.
    Type: Grant
    Filed: December 8, 1992
    Date of Patent: August 24, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Ikuro Masuda, Kazuo Kato, Takao Sasayama, Yoji Nishio, Shigeo Kuboki, Masahiro Iwamura
  • 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: 5133064
    Abstract: An information processing system having an original clock oscillator for delivering at least one original clock signal K defined as a first clock signal and a plurality of information processing units supplied with the original clock signal K, wherein each information processing unit comprises clock generating means for generating at least one second clock signal K.sub.1 which is phase-locked with the original clock signal K and which has a predetermined duty cycle and a logic device whose operation timing is controlled by the second clock signal K.sub.1, and the operation timing of an interface provided between at least one pair of logic devices is synchronously controlled by the clock signal K.sub.1.
    Type: Grant
    Filed: April 22, 1988
    Date of Patent: July 21, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Hotta, Kozaburo Kurita, Masahiro Iwamura, Hideo Maejima, Shigeya Tanaka, Tadaaki Bandoh, Yasuhiro Nakatsuka, Kazuo Kato, Sin-ichi Sinoda