Patents by Inventor Jun Etoh

Jun Etoh 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: 5579256
    Abstract: Herein disclosed is a semiconductor memory device, in which peripheral circuits are arranged in a cross area of a semiconductor chip composed of the longitudinal center portions and the transverse center portions, and in which memory arrays are arranged in the four regions which are divided by the cross area. Thanks to this structure in which the peripheral circuits are arranged at the center portion of the chip, the longest signal transmission paths can be shortened to about one half of the chip size to speed up the DRAM which is intended to have a large storage capacity.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: November 26, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiko Kajigaya, Kazuyuki Miyazawa, Manabu Tsunozaki, Kazuyoshi Oshima, Takashi Yamazaki, Yuji Sakai, Jiro Sawada, Yasunori Yamaguchi, Tetsurou Matsumoto, Shinji Udo, Hiroshi Yoshioka, Hirokazu Saito, Mitsuhiro Takano, Makoto Morino, Sinichi Miyatake, Eiji Miyamoto, Yasuhiro Kasama, Akira Endo, Ryoichi Hori, Jun Etoh, Masashi Horiguchi, Shinichi Ikenaga, Atsushi Kumata
  • Patent number: 5539279
    Abstract: A highly reliable and high speed ferroelectric memory having a high degree of integration. In a ferroelectric memory having a multiple of memory cells M1, each constituted by one transistor and one ferroelectric capacitor, in the normal operation, the ferroelectric memory is used as a volatile memory in which a voltage on a storage node ST1 stores information in a DRAM mode. Both the electric potential at the plate PL1 of the ferroelectric capacitor and a precharge electric potential on a data line DL1(j) are Vcc/2. When the a power supply voltage is turned on, a polarization state is detected as a ferroelectric memory of a plate electric potential of Vcc/2 and a precharge electric potential of Vss (or Vcc) and the read operation is performed a FERAM mode.
    Type: Grant
    Filed: December 22, 1994
    Date of Patent: July 23, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Kan Takeuchi, Masashi Horiguchi, Masakazu Aoki, Katsumi Matsuno, Takeshi Sakata, Jun Etoh, Yoshinobu Nakagome
  • Patent number: 5526313
    Abstract: Disclosed is a one-chip ULSI which can carry out the fixed operation in a wide range of power supply voltage (1 V to 5.5 V). This one-chip ULSI is composed of a voltage converter circuit(s) which serves to a fixed internal voltage for a wide range of power supply voltage, an input/output buffer which can be adapted to several input/output levels, a dynamid RAM(s) which can operate at a power supply voltage of 2 V or less, etc. This one-chip ULSI can be applied to compact and portable electronic devices such as a lap-top type personal computer, an electronic pocket note book, a solid-state camera, etc.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: June 11, 1996
    Assignees: Hitachi Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Jun Etoh, Kiyoo Itoh, Yoshiki Kawajiri, Yoshinobu Nakagome, Eiji Kume, Hitoshi Tanaka
  • Patent number: 5467314
    Abstract: In an address multiplexed dynamic random access memory (RAM) which has both a normal operation mode and a test mode capability, the test mode is initiated in response to particular signal level combinations of both the row address strobe (RAS) and column address strobe (CAS) signals and the write enable (WE) signal. Since the signal level combinations employed in connection with implementing the test mode are unused in the normal operating mode of the dynamic RAM, additional external terminals are unneeded. This dynamic RAM employs multiplexing circuitry on both the input side as well as on the output side of the dynamic RAM, which multiplexing circuitry is controlled during normal operation by select signals from a decoder and during the test mode by a test signal which allows accessing of data at all of the common complementary data lines by the testing circuitry so as to determine whether there is consistency or inconsistency of the data being read out for testing.
    Type: Grant
    Filed: July 18, 1994
    Date of Patent: November 14, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Kazuyuki Miyazawa, Katsuhiro Shimohigashi, Jun Etoh, Katsutaka Kimura
  • Patent number: 5455797
    Abstract: An apparatus includes a constant voltage generator for generating a voltage based on a difference between threshold voltages of two MOS transistors, and a voltage sampling device for sampling the output voltage of the constant voltage generator circuit, wherein the voltage sampling device samples the output voltage of the constant voltage generator before an electric source switch for the constant voltage generator is turned off.
    Type: Grant
    Filed: October 4, 1994
    Date of Patent: October 3, 1995
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Jun Etoh, Yoshinobu Nakagome, Hitoshi Tanaka, Koji Kawamoto, Masakazu Aoki
  • Patent number: 5426616
    Abstract: A voltage conversion circuit of the present invention is equipped with means for generating a first voltage stabilized with respect to ground potential of a semiconductor integrated circuit device including the circuit, means for generating second voltage stabilized with respect to an external supply voltage of the semiconductor integrated circuit device, and selection means for selecting either the first voltage or the second voltage. The first voltage age, stabilized with respect to the ground potential, is selected and used as the voltage at the time of normal operation, and the second voltage, stabilized with respect to the external supply voltage, is selected and used at the time of aging test. In this case, means for trimming the first voltage and/or the second voltage is, preferably, provided to raise the voltage accuracy.
    Type: Grant
    Filed: May 16, 1994
    Date of Patent: June 20, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Kazuhiko Kajigaya, Tetsu Udagawa, Kyoko Ishii, Manabu Tsunozaki, Kazuyoshi Oshima, Masashi Horiguchi, Jun Etoh, Masakazu Aoki, Shin'ichi Ikenaga, Kiyoo Itoh
  • Patent number: 5402376
    Abstract: In a semiconductor memory, switch circuits are provided so as to inhibit voltage and signal supplies to each of the normal memory blocks when so required. On the other hand, a ROM is provided on the chip so as to store the address of a defective memory block which consumes an excessively large stand-by current when the semiconductor memory is in the stand-by mode. The switch circuits are controlled by the output of the ROM so as to inhibit the voltage and signal supply to the defective memory block. Then, a spare memory block which is substituted for the defective normal memory block receives the voltage and signal supply.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: March 28, 1995
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Masashi Horiguchi, Jun Etoh, Masakazu Aoki, Yoshinobu Nakagome, Hitoshi Tanaka, Kiyoo Itoh
  • Patent number: 5384740
    Abstract: An apparatus includes a constant voltage generator for generating a voltage based on a difference between threshold voltages of two MOS transistors, and a voltage sampling device for sampling the output voltage of the constant voltage generator circuit, wherein the voltage sampling device samples the output voltage of the constant voltage generator before an electric source switch for the constant voltage generator is turned off.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: January 24, 1995
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering
    Inventors: Jun Etoh, Yoshinobu Nakagome, Hitoshi Tanaka, Koji Kawamoto, Masakazu Aoki
  • Patent number: 5383080
    Abstract: A voltage limiter circuit is disposed in a semiconductor IC chip in order to reduce an operating voltage of an internal circuit of a scaled-down element. A small capacitance of a Vcc wiring by the disposition constitutes a resonance circuit together with an inductance of the Vcc wiring. Resonance at the resonance circuit causes large variation of a supply current and noise. An additional capacitance is connected between the Vcc wiring and a Vss wiring in order to suppress the variation and noise. The capacitance is formed by a PN junction and is connected in series to a damping resistance.
    Type: Grant
    Filed: July 24, 1992
    Date of Patent: January 17, 1995
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Jun Etoh, Masakazu Aoki, Masashi Horiguchi, Shigeki Ueda, Hitoshi Tanaka, Kazuhiko Kajigaya, Tsugio Takahashi, Hiroshi Kawamoto
  • Patent number: 5376839
    Abstract: Practical structures of an ultra large scale semiconductor integrated (ULSI) circuit especially a dynamic random access memory of 16M bits or more are involved. The ULSI circuit uses internal operating voltages and how to construct a reference voltage generating circuit and a voltage limiter circuit in the ULSI circuit is a matter of importance. The operation of the reference voltage generating circuit and voltage limiter circuit can be stabilized, characteristics of these circuits are improved, and layout of these circuits as applied to memory cell array, peripheral circuits and the like can be improved. Improved methods of testing these circuits are provided.
    Type: Grant
    Filed: August 9, 1993
    Date of Patent: December 27, 1994
    Assignees: Hitachi Ltd., VLSI Engineering Corporation
    Inventors: Masashi Horiguchi, Masakazu Aoki, Kiyoo Itoh, Yoshinobu Nakagome, Norio Miyake, Takaaki Noda, Jun Etoh, Hitoshi Tanaka, Shin'ichi Ikenaga
  • Patent number: 5331596
    Abstract: An address multiplexed dynamic random access memory (RAM) which has both a normal operation mode and a test mode capability is provided. The test mode is initiated in response to particular signal level combinations of both the row address strobe (RAS) and column address strobe (CAS) signals and the write enable (WE) signal. Since the signal level combinations employed in connection with implementing the test mode are unused in the normal operating mode of the dynamic RAM, additional external terminals are unneeded. This dynamic RAM employs multiplexing circuitry on both the input side as well as on the output side of the dynamic RAM, which multiplexing circuitry is controlled during normal operation by select signals from a decoder and during the test mode by a test signal which allows accessing of data at all of the common complementary data lines by the testing circuitry so as to determine whether there is consistency or inconsistency of the data being read out for testing.
    Type: Grant
    Filed: May 26, 1992
    Date of Patent: July 19, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Kazuyuki Miyazawa, Katsuhiro Shimohigashi, Jun Etoh, Katsutaka Kimura
  • Patent number: 5297097
    Abstract: Disclosed is a one-chip ULSI which can carry out fixed operations for a wide range of power supply voltages (1 V to 5.5 V). This one-chip ULSI is composed of a voltage converter circuit(s) which provides a fixed internal voltage for a wide range of power supply voltages, an input/output buffer which can be adapted to several input/out interface levels, a dynamic or volatile RAM(s) which can operate at a power supply voltage of 2 V or less, etc. This one-chip ULSI can be applied to compact and portable electronic devices such as a lap-top type personal computer, an electronic pocket note book, a solid-state camera, etc.
    Type: Grant
    Filed: June 14, 1989
    Date of Patent: March 22, 1994
    Assignees: Hitachi Ltd., Hitachi VLSI Engineering
    Inventors: Jun Etoh, Kiyoo Itoh, Yoshiki Kawajiri, Yoshinobu Nakagome, Eiji Kume, Hitoshi Tanaka
  • Patent number: 5265055
    Abstract: A redundancy technique is introduced for a semiconductor memory and, more particularly a redundancy technique for a dynamic random access memory (DRAM) having a storage capacity of 16 mega bits or more. In such a DRAM, the efficiency of the redundancy technique is reduced, since a memory array is divided into a large number of memory mats.
    Type: Grant
    Filed: December 27, 1991
    Date of Patent: November 23, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Masashi Horiguchi, Jun Etoh, Masakazu Aoki, Kiyoo Itoh
  • Patent number: 5262999
    Abstract: Disclosed is a one-chip ULSI which can carry out the fixed operation in a wide range of power supply voltage (1 V to 5.5 V). This one-chip ULSI is composed of a voltage converter circuit(s) which serves to a fixed internal voltage for a wide range of power supply voltage, an input/output buffer which can be adapted to several input/output levels, a dynamid RAM(s) which can operate at a power supply voltage of 2 V or less, etc. This one-chip ULSI can be applied to compact and portable electronic devices such as a lap-top type personal computer, an electronic pocket note book, a solid-state camera, etc.
    Type: Grant
    Filed: March 24, 1992
    Date of Patent: November 16, 1993
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Jun Etoh, Kiyoo Itoh, Yoshiki Kawajiri, Yoshinobu Nakagome, Eiji Kume, Hitoshi Tanaka
  • Patent number: 5262993
    Abstract: In a semiconductor memory, switch circuits are provided so as to inhibit voltage and signal supplies to each of the normal memory blocks when so required. On the other hand, a ROM is provided on the chip so as to store the address of a defective memory block which consumes an excessively large stand-by current when the semiconductor memory is in the stand-by mode. The switch circuits are controlled by the output of the ROM so as to inhibit the voltage and signal supply to the defective memory block. Then, a spare memory block which is substituted for the defective normal memory block receives the voltage and signal supply.
    Type: Grant
    Filed: November 6, 1991
    Date of Patent: November 16, 1993
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Masashi Horiguchi, Jun Etoh, Masakazu Aoki, Yoshinobu Nakagome, Hitoshi Tanaka, Kiyoo Itoh
  • Patent number: 5254880
    Abstract: Practical structures of an ultra large scale semiconductor integrated (ULSI) circuit especially a dynamic random access memory of 16M bits or more are involved. The ULSI circuit uses internal operating voltages and how to construct a reference voltage generating circuit and a voltage limiter circuit in the ULSI circuit is a matter of importance. The operation of the reference voltage generating circuit and voltage limiter circuit can be stabilized, characteristics of these circuits are improved, and layout of these circuits as applied to memory cell array, peripheral circuits and the like can be improved. Improved methods of testing these circuits are provided.
    Type: Grant
    Filed: April 3, 1992
    Date of Patent: October 19, 1993
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Masashi Horiguchi, Masakazu Aoki, Kiyoo Itoh, Yoshinobu Nakagome, Norio Miyake, Takaaki Noda, Jun Etoh, Hitoshi Tanaka, Shin ichi Ikenaga
  • Patent number: 5179539
    Abstract: Practical structures of an ultra large scale semiconductor integrated (ULSI) circuit especially a dynamic random access memory of 16 M bits or more are involved. The ULSI circuit uses internal operating voltages and how to construct a reference voltage generating circuit and a voltage limiter circuit in the ULSI circuit is a matter of importance. The operation of the reference voltage generating circuit and voltage limiter circuit can be stabilized, characteristics of these circuits are improved, and layout of these circuits as applied to memory cell array, peripheral circuits and the like can be improved. Improved methods of testing these circuits are provided.
    Type: Grant
    Filed: April 8, 1992
    Date of Patent: January 12, 1993
    Assignee: Hitachi, Ltd., Hitachi Vlsi Engineering Corporation
    Inventors: Masashi Horiguchi, Masakazu Aoki, Kiyoo Itoh, Yoshinobu Nakagome, Norio Miyake, Takaaki Noda, Jun Etoh, Hitoshi Tanaka, Shin'ichi Ikenaga
  • Patent number: 5117393
    Abstract: An address multiplexed dynamic RAM device is provided which is capable of initiating (setting) and terminating (resetting) the test mode in response to the signal level combinations of the row address and column address strobe signals and the write enable signal. The signal level combinations employed correspond to those which are unused in the normal operating mode thereby obviating the need for providing additional external control signal terminals. In addition to writing predetermined data in selected memory cells during the test mode, verficiation of the predetermined data is also implemented during the read phase of the test mode.
    Type: Grant
    Filed: January 31, 1991
    Date of Patent: May 26, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Kazuyuki Miyazawa, Katsuhiro Shimohigashi, Jun Etoh, Katsutaka Kimura
  • Patent number: 5086414
    Abstract: A semiconductor circuit having a plurality of circuit blocks, each having latch circuits each one thereof being controlled by an internally provided clock signal for preventing malfunction of the circuit. Each circuit is provided with the latch function so that the cycle time is made shorter than the access time. Moreover, the latch means are driven in such a manner that the adjoining ones are prevented from being put to through-state simultaneously, whereby malfunction is prevented.
    Type: Grant
    Filed: November 15, 1989
    Date of Patent: February 4, 1992
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd.
    Inventors: Hiroaki Nambu, Noriyuki Homma, Kunihiko Yamaguchi, Kazuo Kanetani, Youji Idei, Kenichi Ohhata, Yoshiaki Sakurai, Jun Etoh
  • Patent number: 4994688
    Abstract: Practical structures of an ultra large scale semiconductor integrated (ULSI) circuit especially a dynamic random access memory of 16 M bits or more are involved. The ULSI circuit uses internal operating voltages and how to construct a reference voltage generating circuit and a voltage limiter circuit in the ULSI circuit is a matter of importance. The operation of the reference voltage generating circuit and voltage limiter circuit can be stabilized, characteristics of these circuits are improved, and layout of these circuits as applied to memory cell array, peripheral circuits and the like can be improved. Improved methods of testing these circuits are provided.
    Type: Grant
    Filed: March 15, 1989
    Date of Patent: February 19, 1991
    Assignees: Hitachi Ltd., Hitachi VLSI Engineering Corporation
    Inventors: Masashi Horiguchi, Masakazu Aoki, Kiyoo Itoh, Yoshinobu Nakagome, Norio Miyake, Takaaki Noda, Jun Etoh, Hitoshi Tanaka, Shin'ichi Ikenaga