Patents by Inventor Masamichi Ishihara

Masamichi Ishihara 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: 5426613
    Abstract: A semiconductor memory device is provided which includes a substrate arrangement which is suitable for forming a large number of types of DRAMs having different package specifications, different bit structure and different operating modes. In conjunction with this, the bonding pads are arranged at optimum locations for accommodating the different package types. Various layout arrangements are also provided to minimize space and to improve access time. Additional features are provided, including improved output buffer circuitry, protection circuitry and testing methods to facilitate operation of the semiconductor memory device.
    Type: Grant
    Filed: November 6, 1992
    Date of Patent: June 20, 1995
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Yasushi Takahashi, Hidetoshi Iwai, Satoshi Oguchi, Hisashi Nakamura, Hiroyuki Uchiyama, Toshitugu Takekuma, Shigetoshi Sakomura, Kazuyuki Miyazawa, Masamichi Ishihara, Ryoichi Hori, Takeshi Kizaki, Yoshihisa Koyama, Haruo Ii, Masaya Muranaka, Hidetomo Aoyagi, Hiromi Matsuura
  • Patent number: 5410507
    Abstract: A dynamic RAM provided with a data retention mode intended for low power consumption is provided. In the data retention mode, the current supply capabilities of voltage generation circuits which generate decreased voltage, increased voltage, reference voltage, etc., are limited in the range in which information retention operation in memory cells can be maintained, and the number of selected memory mats in the data retention mode is increased with respect to that of memory mats selected in the normal read/write mode and refresh mode. Special modes such as the data retention mode are set by combining an address strobe signal and other control signals and dummy CBR refresh is executed to release the special mode.
    Type: Grant
    Filed: November 16, 1992
    Date of Patent: April 25, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Masanori Tazunoki, Shigetoshi Sakomura, Toshitsugu Takekuma, Yutaka Ito, Kazuya Ito, Wataru Arakawa, Hidetoshi Iwai, Toshiyuki Sakuta, Masamichi Ishihara
  • Patent number: 5359561
    Abstract: A semiconductor memory device is provided which includes a plurality of data lines, at least one redundant data line, one common data line, a plurality of column switches installed between the plurality of data lines and the redundant data line and one common data line, and a column decoder for controlling the plurality of column switches. The column decoder operates to turn the column switch on. The column switch is connected to a plurality of data lines, excluding any defective data and redundant data lines during the test mode state.
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: October 25, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Shigetoshi Sakomura, Kazuya Ito, Hidetoshi Iwai, Toshiyuki Sakuta, Masamichi Ishihara, Tomoshi Matsumoto, deceased
  • Patent number: 5332922
    Abstract: A pair of DRAM chips 1A and 1B are mounted opposedly to each other with wiring means such as lead frames put therebetween, the lead frames being substantially integral with external terminals 3B. Then, these DRAM chips and lead frames are connected together by the conventional wire bonding method. Each chip is bonded with an associated lead frame and each lead frame is disposed as plural lead frame conductors contacting mutually lead frame conductors associated with similarly function bonding pads, i.e. external terminals of the chips, of the other one of the pair of chips. Ones or plural pairs of the thus-connected DRAM chips and lead frames are stacked and corresponding leads of the lead frames are connected in common to form a laminate. The plural DRAM chips thus mounted are activated selectively in accordance with a predetermined chip selection signal.
    Type: Grant
    Filed: April 26, 1991
    Date of Patent: July 26, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Satoshi Oguchi, Masamichi Ishihara, Kazuya Ito, Gen Murakami, Ichiro Anjoh, Toshiyuki Sakuta, Yasunori Yamaguchi, Yasuhiro Kasama, Tetsu Udagawa, Eiji Miyamoto, Youichi Matsuno, Hiroshi Satoh, Atsusi Nozoe
  • Patent number: 5289416
    Abstract: An arrangement is provided for preventing DC defects in a memory or logic device after switching to a redundant circuit, improving the product yield of the device by cutting a leakage current path through a defective element or circuit. The cutting points formed by the predetermined wirings as a whole or a part thereof are provided to the device. A probe test of the formed chip is executed under the wafer condition by predetermined test equipment, and wiring correction data regarding the cutting of the cutting points is generated based on the result of test. Moreover, this wiring correction data is transmitted in an on-line fashion to the wiring correction equipment so that the corresponding cutting points can be cut. The wiring correction equipment can be formed by an EB direct writing apparatus, an FIB apparatus or a laser repair apparatus.
    Type: Grant
    Filed: January 14, 1992
    Date of Patent: February 22, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Hidetoshi Iwai, Masamichi Ishihara, Kazuya Ito, Wataru Arakawa, Yoshinobu Nakagome
  • Patent number: 5276346
    Abstract: Disclosed is a semiconductor device having an internal circuit protected by an electrostatoc protective circuit, the internal circuit and electrostatic protective circuit being formed on the same semiconductor substrate. The internal circuit includes MIS elements and has a double-diffused drain structure, while the protective circuit has a single-diffused drain structure. The internal circuit can be, e.g., a DRAM, and the protective circuit can have diffused resistors and clamping MIS elements. The single-diffused drain structure can be formed in the protective circuit on the semiconductor substrate, while providing double-diffused drain structure in the internal circuit on the same substrate, by: (1) scanning the ion implanting apparatus to avoid ion implantation of the first ions into the region of the protective circuit, and/or (2) forming a photoresist film over the region of the protective circuit to prevent ion implanation of the first ions into the protective circuit region.
    Type: Grant
    Filed: January 2, 1992
    Date of Patent: January 4, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Hidetoshi Iwai, Kazumichi Mitsusada, Masamichi Ishihara, Tetsuro Matsumoto, Kazuyuki Miyazawa, Hisao Katto, Kousuke Okuyama
  • Patent number: 5217917
    Abstract: A semiconductor memory device is provided which includes a substrate arrangement which is suitable for forming a large number of types of DRAMs having different package specifications, different bit structure and different operating modes. In conjunction with this, the bonding pads are arranged at optimum locations for accommodating the different package types. Various layout arrangements are also provided to minimize space and to improve access time. Additional features are provided, including improved output buffer circuitry, protection circuitry and testing methods to facilitate operation of the semiconductor memory device.
    Type: Grant
    Filed: March 20, 1990
    Date of Patent: June 8, 1993
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Yasushi Takahashi, Hidetoshi Iwai, Satoshi Oguchi, Hisashi Nakamura, Hiroyuki Uchiyama, Toshitugu Takemuma, Shigetoshi Sakomura, Kazuyuki Miyazawa, Masamichi Ishihara, Ryoichi Hori, Takeshi Kizaki, Yoshihisa Koyama, Haruo Ii, Masaya Muranaka, Hidetomo Aoyagi, Hiromi Matsuura
  • Patent number: 5208782
    Abstract: A semiconductor integrated circuit memory structure is provided which uses macro-cellulated circuit blocks that can permit a very large storage capability (for example, on the order of 64 Mbits in a DRAM) on a single chip. To achieve, this, a plurality of macro-cellulated memory blocks can be provided, with each of the memory blocks including a memory array as well as additional circuitry such as address selection circuits and input/output circuits. Other peripheral circuits are provided on the chip which are common to the plurality of macro-cell memory blocks. The macro-cell memory blocks themselves can be formed in an array so that their combined storage capacity will form the large overall storage capacity of the chip. The combination of the macro-cell memory blocks and the common peripheral circuitry for controlling the memory blocks permits a faster and more efficient refreshing operation for a DRAM. This is enhanced by a LOC (Lead On Chip) arrangement used in conjunction with the memory blocks.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: May 4, 1993
    Assignees: Hitachi, Ltd., Hitachi Vlsi Engineering Corp.
    Inventors: Toshiyuki Sakuta, Masamichi Ishihara, Kazuyuki Miyazawa, Masanori Tazunoki, Hidetoshi Iwai, Hisashi Nakamura, Yasushi Takahashi, Toshio Maeda, Hiromi Matsuura, Ryoichi Hori, Toshio Sasaki, Osamu Sakai, Hiroyuki Uchiyama, Eiji Miyamoto, Kazuyoshi Oshima, Yasuhiro Kasama
  • Patent number: 5151772
    Abstract: A semiconductor integrated circuit device is provided which includes a memory cell array located in a generally central area of a semiconductor substrate with peripheral circuits located at both ends of the semiconductor substrate. A wiring layer is also provided which couples the peripheral circuits to one another. This wiring layer is arranged to have a double-layer structure of first and second aluminum layers which are electrically coupled to one another.
    Type: Grant
    Filed: November 20, 1990
    Date of Patent: September 29, 1992
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Yasushi Takahashi, Hiromi Matsuura, Yoshihisa Koyama, Masaya Muranaka, Katsutaka Kimura, Kazuyuki Miyazawa, Masamichi Ishihara, Hidetoshi Iwai
  • Patent number: 5021998
    Abstract: Disclosed are measurement (observation) pads for judging whether or not a dynamic random access memory (DRAM) adopting a shared sense system is functioning as designed. Concretely, measurement pads are formed by the step of forming a second layer of wiring respectively connected to pairs of complementary data lines which are formed by the step of forming a first layer of wiring, and the signal waveforms of the pairs of complementary data lines are measured using the measurement pads. Further, the measurement pads are provided between wiring layers which become fixed potentials in, at least, the operation of measuring data. In addition, each of the measurement pads is used in common by data lines which are respectively connected to two memory cells located in different memory cell mats.
    Type: Grant
    Filed: April 18, 1989
    Date of Patent: June 4, 1991
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering
    Inventors: Yukihide Suzuki, Masaya Muranaka, Masamichi Ishihara
  • Patent number: 5018109
    Abstract: A microprocessor or the like supplies address signals for memory access according to its own operation speed irrespective of operation speed of a memory. A plurality of registers which take a plurality of address signals inputted in asynchronous state are installed in the memory. The memory access is performed according to sequence of the address signals taken in these plural registers.
    Type: Grant
    Filed: January 16, 1990
    Date of Patent: May 21, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Shinoda, Masamichi Ishihara
  • Patent number: 4991139
    Abstract: A semiconductor memory device is provided which includes a plurality of data lines coupled to memory cells and to a detecting arrangement for detecting if logical levels of each of the data lines coincide to each other or not. A test read arrangement is also provided which stores the same information, in advance, in plural memory cells so that if there is a defect in one of the memory cells, this can be detected by the detecting arrangement.
    Type: Grant
    Filed: August 4, 1988
    Date of Patent: February 5, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Yasushi Takahashi, Masamichi Ishihara, Kazuhiko Kajigaya, Toshiyuki Sakuta
  • Patent number: 4951122
    Abstract: The present invention relates to a technique in which the pellet fixing parts of a lead frame of the tabless type or the type having no die pads are molded in or coated with a resin beforehand in order to enhance the reliability of a resin-encapsulated IC having become important with enlargement in the size of the chip of a memory IC or the like and reduction in the size of a resin package, and a resin package structure in which the technique of the lead frame having no die pads is applied to flat packaging so as to lessen reflow cracks.
    Type: Grant
    Filed: May 27, 1988
    Date of Patent: August 21, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Kunihiro Tsubosaki, Gen Murakami, Toshiyuki Sakuta, Masamichi Ishihara, Satoru Ito, Yasuo Mori
  • Patent number: 4928281
    Abstract: A semiconductor memory includes a memory array which outputs storage data, at least one data unit at a time, each data unit having a plurality of bits including a parity bit, a parity check circuit for performing a parity check on storage data, at least one data unit at a time, input for both to and output from the memory array, and an external terminal for outputting the result of the parity check.
    Type: Grant
    Filed: June 10, 1987
    Date of Patent: May 22, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Hinoko Kurosawa, Kazuya Itoh, Hisashi Nakamura, Masamichi Ishihara
  • Patent number: 4922993
    Abstract: The disclosed method forms a zinc sleeve on an insulator pin by dipping the insulator pin in molten zinc at about 450.degree.-650.degree. C. to heat and wet the insulator pin with the molten zinc, setting the hot and wetted insulator pin in a die having an open-top cavity in such a manner that an annular open-top molding cavity is defined around the insulator, the die being at about 50.degree.-300.degree. C. when receiving the insulator pin, pouring molten zinc in the annular molding cavity through its open top, and solidifying the zinc thus poured.
    Type: Grant
    Filed: January 25, 1989
    Date of Patent: May 8, 1990
    Assignee: NGK Insulators, Ltd.
    Inventors: Hiroto Matsuo, Iwaji Kawamoto, Masamichi Ishihara, Takaaki Nakagawa
  • Patent number: 4912679
    Abstract: A microprocessor or the like supplies a plurality of address signals for memory access according to its own operation speed irrespective of the operation speed of a memory. A plurality of registers receives and stores the plurality of address signals which are inputted in an asynchronous state. The memory access is performed according to a sequence signals of the address signals stored in the plurality of registers.
    Type: Grant
    Filed: January 15, 1988
    Date of Patent: March 27, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Shinoda, Masamichi Ishihara
  • Patent number: 4858190
    Abstract: A semiconductor memory is provided in which a column decoder is used commonly for the random input and output and the serial input/output by providing both a signal path for transmitting signals in parallel to the data lines of a memory array and a latch circuit and a switch path for connecting said latch circuit and a serial input/output common data line in response to a selection signal generated by a shift register, and by feeding the output signal of a random input/output column decoder as an initial value to the individual bits of said shift register.
    Type: Grant
    Filed: January 20, 1987
    Date of Patent: August 15, 1989
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Yasunori Yamaguchi, Akirahiko Yoshida, Masami Nei, Masamichi Ishihara, Yukio Yamamoto
  • Patent number: 4819213
    Abstract: A semiconductor memory for serially reading data of memory cells connected to the selected one word line based on the clock signal which defines a picture element and for writing the write data serially input to the latch circuit based on such clock signal to the memory cells, during the horizontal blanking time of a CRT monitor.
    Type: Grant
    Filed: December 11, 1986
    Date of Patent: April 4, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Yasunori Yamaguchi, Masamichi Ishihara
  • Patent number: 4802135
    Abstract: A pseudo static RAM is provided which uses a one MOSFET dynamic RAM cell, in which two functions of a page mode and a static column mode are realized by using an address buffer having a function to transmit address signals fed from external terminals as they are and a latch function to latch the address signals fed from the external terminals in synchronism with predetermined control signals fed from the external terminals. The address buffer also has a multiplexer function to selectively incorporate the address signals from the external terminals and the address signals produced in the inside of the RAM so that the address buffer and an internal address signal generating circuit may be controlled by external control terminals to make possible the continuous access by the internal address signals.
    Type: Grant
    Filed: September 2, 1986
    Date of Patent: January 31, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Shinoda, Masamichi Ishihara
  • Patent number: 4562555
    Abstract: An address multiplex type system for a dynamic RAM includes a memory cell array having a plurality of memory cells which are simultaneously selected by signals output from an address decoder, a decoder, and a shift register. The dynamic RAM further includes a selecting circuit which receives a plurality of address signals applied externally through one of a plurality of pins of a package in a time-sharing manner and makes it possible to write or read data into or from one memory cell of the plurality of memory cells selected. The dynamic RAM can read out or write in serially data of a plurality of memory cells selected from the memory cell array when a shift register operates. The dynamic RAM can also read or write data serially into or from a plurality of memory cells selected from the memory cell array simply by connecting the pin to a predetermined potential.
    Type: Grant
    Filed: September 23, 1983
    Date of Patent: December 31, 1985
    Assignees: Hitachi, Ltd., Hitachi Microcomputer Engineering Ltd.
    Inventors: Yoshiaki Ouchi, Masamichi Ishihara, Tetsuro Matsumoto, Kazuyuki Miyazawa