Patents by Inventor Seiji Sawada

Seiji Sawada 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).

  • Publication number: 20030218216
    Abstract: A bare chip is provided with a pad for activation/deactivation control to which a deactivation control signal for converting a bare chip that has been detected as being defective into the deactivated condition is inputted. When a deactivation control signal is inputted to the pad for activation/deactivation control, internal circuit prevent a signal that has been inputted from the pad for data input/output control from being inputted to an internal circuit located further inside than the input buffer circuit. Thereby, the bare chip that has been detected as being defective can be converted to the deactivated condition. As a result, a semiconductor memory module can be obtained that can be repaired by newly mounting a good function chip without allowing the bare chip that has been detected as being defective to interfere with the functions of the semiconductor memory module.
    Type: Application
    Filed: November 4, 2002
    Publication date: November 27, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasuhiro Matsumoto, Shinji Tanaka, Seiji Sawada, Susumu Tanida, Takahiko Fukiage
  • Patent number: 6636455
    Abstract: This DDR SDRAM, in the normal operation mode, performs a writing operation having a writing latency and, in the testing mode, performs a writing operation without having a writing latency by receiving a data strobe signal and a data signal one clock cycle before a writing command. Therefore, the testing time is short even if the test is carried out at a low frequency.
    Type: Grant
    Filed: May 1, 2002
    Date of Patent: October 21, 2003
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yukiko Maruyama, Seiji Sawada
  • Publication number: 20030189263
    Abstract: A semiconductor module is provided with a module substrate, a plurality of semiconductor chips formed on the module substrate, and a mold resin formed so as to integrally cover the plurality of semiconductor chips. Then, a plurality of trenches is formed on the main surface of the module substrate, so as to be parallel to one side forming the main surface, on the side on which the bare chips are formed. Thereby, a semiconductor module can be obtained wherein it is possible to restrict separation of the mold resin from the module substrate.
    Type: Application
    Filed: September 18, 2002
    Publication date: October 9, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha; Mitsubishi Electric Engineering Company Limited
    Inventors: Seiji Sawada, Hiroyuki Nakao, Tatsuji Kobayashi
  • Publication number: 20030048691
    Abstract: This DDR SDRAM, in the normal operation mode, performs a writing operation having a writing latency and, in the testing mode, performs a writing operation without having a writing latency by receiving a data strobe signal and a data signal one clock cycle before a writing command. Therefore, the testing time is short even if the test is carried out at a low frequency.
    Type: Application
    Filed: May 1, 2002
    Publication date: March 13, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yukiko Maruyama, Seiji Sawada
  • Publication number: 20030031082
    Abstract: An internal clock generating circuit generates internal clock signals at a double speed of an external clock signal in a test mode. An input/output circuit inputs/outputs data in a DDR mode in accordance with the double-speed internal clock signal. Particularly, an output drive signal CLKO has a frequency twice as high as that of the internal clock signal, and a data strobe signal DQS is generated as a signal having a frequency twice as high as that of an external data strobe signal. In such a manner, a semiconductor memory device which inputs and outputs data in a DDR mode at a speed twice as fast as that of an external clock signal can be achieved.
    Type: Application
    Filed: July 8, 2002
    Publication date: February 13, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Seiji Sawada
  • Publication number: 20030012321
    Abstract: A delay locked loop (DLL) circuit comprising: a fundamental phase comparator for detecting a fundamental phase difference of two input signals; a delay circuit; a delay control circuit for adjusting a delay time of the delay circuit in response to an output signal of the fundamental phase comparator; and at least one further phase comparator for detecting a phase difference other than the fundamental phase difference such that an amount of change of the delay time is changed in accordance with the fundamental phase difference.
    Type: Application
    Filed: June 11, 2002
    Publication date: January 16, 2003
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroto Tokutome, Seiji Sawada
  • Publication number: 20020105838
    Abstract: A DLL circuit generates a control clock specifying an operating timing of a data output buffer according to an external clock. The DLL circuit includes a replica delay time adjusting section and a phase control section. The phase control section controls such that a feedback clock and the external clock becomes in phase. The replica delay time adjusting section adjusts a delay time of the feedback clock behind the control clock according to an operating condition serving as a factor for changing a processing time of the data output buffer.
    Type: Application
    Filed: July 19, 2001
    Publication date: August 8, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yukiko Maruyama, Seiji Sawada
  • Patent number: 6426900
    Abstract: A DLL circuit generates a control clock specifying an operating timing of a data output buffer according to an external clock. The DLL circuit includes a replica delay time adjusting section and a phase control section. The phase control section controls such that a feedback clock and the external clock becomes in phase. The replica delay time adjusting section adjusts a delay time of the feedback clock behind the control clock according to an operating condition serving as a factor for changing a processing time of the data output buffer.
    Type: Grant
    Filed: July 19, 2001
    Date of Patent: July 30, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yukiko Maruyama, Seiji Sawada
  • Patent number: 6341089
    Abstract: An internal signal RAS generated in accordance with command input and indicating activation of a row is delayed in accordance with a dock signal int.CLKI, and thereby a sense amplifier activating signal is issued. A time from activation of a word line by a signal WLT to activation of a sense amplifier can be longer than that in a normal case so that a minute leak from a bit line can be detected.
    Type: Grant
    Filed: January 4, 2001
    Date of Patent: January 22, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Seiji Sawada, Kiyohiro Furutani, Mikio Asakura
  • Publication number: 20020003730
    Abstract: The semiconductor memory device has a word configuration determination signal generating circuit including a plurality of generating circuits, each of which is formed of two clocked inverters and two inverters. In a normal operation mode, a test mode signal TX4 is inactivated and a word configuration determination signal [×16E] of an H level is output. In a test mode, the test mode signal TX4 is activated and a word configuration determination signal [×4E] of an H level is output. Thus, in the test mode, the word configuration is switched to the one that is smaller than in the normal operation mode. This allows simultaneous testing of a larger number of semiconductor memory devices.
    Type: Application
    Filed: December 4, 2000
    Publication date: January 10, 2002
    Inventors: Shigekazu Aoki, Seiji Sawada, Mikio Asakura, Takeshi Hamamoto, Masakazu Hirose
  • Publication number: 20020001235
    Abstract: An internal signal RAS generated in accordance with command input and indicating activation of a row is delayed in accordance with a clock signal int.CLKI, and thereby a sense amplifier activating signal is issued. A time from activation of a word line by a signal WLT to activation of a sense amplifier can be longer than that in a normal case so that a minute leak from a bit line can be detected.
    Type: Application
    Filed: January 4, 2001
    Publication date: January 3, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Seiji Sawada, Kiyohiro Furutani, Mikio Asakura
  • Patent number: 6335887
    Abstract: The semiconductor memory device has a word configuration determination signal generating circuit including a plurality of generating circuits, each of which is formed of two clocked inverters and two inverters. In a normal operation mode, a test mode signal TX4 is inactivated and a word configuration determination signal [x16E] of an H level is output. In a test mode, the test mode signal TX4 is activated and a word configuration determination signal [x4E] of an H level is output. Thus, in the test mode, the word configuration is switched to the one that is smaller than in the normal operation mode. This allows simultaneous testing of a larger number of semiconductor memory devices.
    Type: Grant
    Filed: December 4, 2000
    Date of Patent: January 1, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigekazu Aoki, Seiji Sawada, Mikio Asakura, Takeshi Hamamoto, Masakazu Hirose
  • Patent number: 6288965
    Abstract: A reference voltage generating circuit having a fuse for controlling resistance includes a burn-in circuit for supplying burn-in voltage between opposite terminals of the fuse when a control signal is inputted to the burn-in circuit.
    Type: Grant
    Filed: June 13, 2000
    Date of Patent: September 11, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Motoko Hara, Seiji Sawada
  • Patent number: 6235099
    Abstract: A water-dispersed inkjet recording liquid excellent in water resistance and transparency and also excellent in the property of ejection from a nozzle, containing, as a colorant, a water-based dispersion of an organic pigment (A) which is at least one member selected from the group consisting of a quinacridone pigment, a benzimidazolone pigment, an insoluble azo pigment, a fuzed azo pigment, a quinophthalone pigment, a naphthol pigment, a perylene pigment and an isoindolinone pigment and has an average particle diameter of 10 to 150 nm (measured by laser scattering), the water-based dispersion of the organic pigment (A) being obtained by mechanically kneading a mixture containing at least three components of the organic pigment (A), a water-soluble inorganic salt (B) in an amount by weight at least three times as large as the amount of the organic pigment (A) and a water-soluble solvent (C) to finely mill the organic pigment (A), and then removing the water-soluble inorganic salt (B) and the water-soluble solv
    Type: Grant
    Filed: July 28, 1997
    Date of Patent: May 22, 2001
    Assignee: Toyo Ink Manufacturing Co., Ltd.
    Inventors: Seiji Aida, Tsutomu Fujigamori, Hisashi Uraki, Ichiro Toyoda, Sunao Satake, Seiji Sawada, Yasuharu Iida
  • Patent number: 6157992
    Abstract: A read enable signal OEMF activated in response to an input command is applied to an N minus 2 clock shift circuit included in an output control circuit for implementation of ZCAS latency. An output signal of the N minus 2 clock shift circuit and an internal mask instructing signal activated in response to an external mask instructing signal are logically processed and applied to a one-clock shift circuit. According to an output signal OEMQM of one-clock shift circuit, a data output enable signal OEM controlling activation/inactivation of an output buffer circuit is activated/inactivated. Data output controlling portion occupying area of a synchronous dynamic random access memory is reduced and timings of activation/inactivation of data output by different commands are made the same.
    Type: Grant
    Filed: December 16, 1996
    Date of Patent: December 5, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Seiji Sawada, Yasuhiro Konishi
  • Patent number: 6049488
    Abstract: A gate circuit is turned on in synchronization with an internal clock signal at a timing faster than activation of an output buffer circuit, and internal data is transmitted from the gate circuit to an output buffer circuit externally outputting data. Generation of an internal clock signal is stopped at a timing faster than deactivation of the output buffer circuit, and the gate circuit is set to the latching state. According such arrangement, output of invalid data is prevented.
    Type: Grant
    Filed: July 27, 1998
    Date of Patent: April 11, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Seiji Sawada
  • Patent number: 6031024
    Abstract: An inkjet recording ink having excellent water resistance and having excellent ejection stability through a nozzle, which ink is obtained by dispersing colorant particles in a water-based liquid, the colorant particles being a product formed by coating each of resin particles having an average particle diameter of 50 to 300 nm with an organic pigment.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: February 29, 2000
    Assignee: Toyo Ink Manufacturing Co., Ltd.
    Inventors: Hisashi Uraki, Seiji Sawada, Yasuharu Iida, Sunao Satake, Tsutomu Fujigamori, Seiji Aida
  • Patent number: 6014340
    Abstract: In a synchronous semiconductor memory device in which contents of an internal operation is designated by commands applied in synchronization with a clock signal, operations of decoding read, write and precharge commands different from an active command for activating the internal operation are enabled only when the active command is active. Even if a command such as read command other than the active command is applied during an inactive state of internal circuits, other command decoder cannot perform the decoding, so that unnecessary circuit operation can be prevented.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: January 11, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Seiji Sawada
  • Patent number: 6002615
    Abstract: A mask control circuit for generating an internal mask designation signal for masking read data includes a shift circuit incorporating and shifting an applied signal in accordance with an internal column related clock signal CLKD for transmission and a reset means responsive to inactivation of a clock activation signal defining a generation period of the internal column clock signal for resetting the shift circuit in an initial state. An output from the shift circuit is changed from the initial state to another upon clock reapplication, so that the influence by an internal output signal from the shift circuit in the previous application is eliminated, thereby generating a correct internal mask designation signal. A clock shift circuit capable of reducing current consumption without accompanying any malfunction and a synchronous semiconductor memory device using the same is provided.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: December 14, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Seiji Sawada
  • Patent number: 5972087
    Abstract: By use of recording liquid for water based inkjet with pigment and colloidal silica, it is possible to obtain prints print recorded on plain paper with good clearness and high quality and image of the print recorded material with sufficient water resistance and light resistance.
    Type: Grant
    Filed: October 24, 1997
    Date of Patent: October 26, 1999
    Assignee: Toyo Ink Manufacturing Co., Ltd.
    Inventors: Hisashi Uraki, Ichiro Toyoda, Shigeyuki Ehashi, Seiji Aida, Yasuharu Iida, Seiji Sawada, Akio Sato