Patents by Inventor Takayuki Tsukizawa

Takayuki Tsukizawa 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: 8885312
    Abstract: An ESD protection device includes a ceramic base material, a pair of opposed electrodes provided on a surface of or in the ceramic base material, and a discharge auxiliary electrode film arranged to connect the pair of opposed electrodes, wherein the discharge auxiliary electrode film is composed of a material containing, as its main constituents, metallic particles and glass covering the metallic particles. The discharge auxiliary electrode film is formed by providing an electrode paste containing glass-coated metallic particles that have an approximately 15% rate of increase in weight at about 400° C. for about 2 hours in air, a resin binder, and a solvent so as to connect the pair of opposed electrodes to each other, and then firing at a temperature of about 600° C. or more, higher than a softening point of glass of the glass-coated metallic particles, and not +200° C. higher than the softening point.
    Type: Grant
    Filed: February 7, 2012
    Date of Patent: November 11, 2014
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takahiro Sumi, Takahiro Kitadume, Jun Adachi, Takayuki Tsukizawa, Masanori Okamoto
  • Publication number: 20140327993
    Abstract: Provided is an ESD protection device having excellent discharge characteristics at a low applied voltage. An ESD protection device includes a first discharge electrode and a second discharge electrode that are disposed so as to face each other, a discharge auxiliary electrode formed so as to span between the first discharge electrode and the second discharge electrode, and an insulator base that holds the first discharge electrode, the second discharge electrode, and the discharge auxiliary electrode. The discharge auxiliary electrode includes a plurality of metal particles (22) containing a first metal as a main component. Fine irregularities are formed on the surfaces of the metal particles (22). More specifically, the metal particles (22) has a fractal dimension D of 1.03 or more. Since electric charges are concentrated on the fine irregularities, discharge can be generated in the discharge auxiliary electrode by applying a relatively low voltage.
    Type: Application
    Filed: July 16, 2014
    Publication date: November 6, 2014
    Inventors: Takahiro Sumi, Kumiko Ishikawa, Jun Adachi, Takayuki Tsukizawa
  • Patent number: 8847726
    Abstract: In a method for manufacturing an ESD protection device and an ESD protection device, on sheets defining insulating layers, portions defining a first connection conductor and a second connection conductor and a portion defining a mixed portion are formed, then the sheets are laminated and heated. The mixed portion is formed using a mixed portion formation material containing a cavity formation material and a solid component containing at least one of (i) a metal and a semiconductor, (ii) a metal and ceramic, (iii) a metal, a semiconductor, and ceramic, (iv) a semiconductor and ceramic, (v) a semiconductor, (vi) a metal coated with an inorganic material, (vii) a metal coated with an inorganic material and a semiconductor, (viii) a metal coated with an inorganic material and ceramic, and (ix) a metal coated with an inorganic material, a semiconductor, and ceramic. The cavity formation material disappears during heating.
    Type: Grant
    Filed: August 3, 2012
    Date of Patent: September 30, 2014
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tetsuya Ikeda, Takayuki Tsukizawa
  • Publication number: 20140211441
    Abstract: A wireless apparatus has a board, a power amplifier high-frequency IC chip, and a process variations detector. The process variations detector monitors a circuit characteristic variation amount due to process variations. An underfill having a parameter value calculated using the monitored circuit characteristic variation amount is applied between the board and the high-frequency IC chip and the mounting board. As a result, the wireless apparatus exhibits a desired circuit characteristic even with process variations and influence of the underfill.
    Type: Application
    Filed: October 19, 2012
    Publication date: July 31, 2014
    Inventor: Takayuki Tsukizawa
  • Publication number: 20140191360
    Abstract: An ESD protection device includes a first discharge electrode and a second discharge electrode arranged to oppose each other, a discharge supporting electrode formed so as to span between the first and second discharge electrodes, and an insulator substrate that retains the first and second discharge electrodes and the discharge supporting electrode. The discharge supporting electrode is constituted by a group of a plurality of metal particles each coated with a semiconductor film containing silicon carbide. This discharge supporting electrode is obtained by firing a semiconductor-metal complex powder in which a semiconductor powder composed of silicon carbide is fixed to surfaces of metal particles. Selection is made so that the relationship between a coating amount Q [wt %] of the semiconductor powder in the semiconductor-metal complex powder and a specific surface area S [m2/g] of the metal powder satisfies Q/S?8.
    Type: Application
    Filed: March 13, 2014
    Publication date: July 10, 2014
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Takahiro Sumi, Jun Adachi, Takayuki Tsukizawa
  • Publication number: 20140192447
    Abstract: An ESD protection device having high insulation reliability and good discharge properties is provided. In producing an ESD protection device that includes a first discharge electrode and a second discharge electrode arranged to oppose each other, a discharge supporting electrode formed so as to span between the first and second discharge electrodes, and an insulator substrate that retains the first and second discharge electrodes and the discharge supporting electrode, a paste for forming a discharge supporting electrode is used and this paste contains, in addition to a powder of an alkali metal compound and/or an alkaline earth metal compound, a metal powder with a network-forming oxide adhered to particle surfaces, a metal powder and a semiconductor powder with a network-forming oxide adhered to particle surfaces, or a metal powder with a network-forming oxide adhered to particle surfaces and a semiconductor powder with a network-forming oxide adhered to particle surfaces.
    Type: Application
    Filed: March 12, 2014
    Publication date: July 10, 2014
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Takahiro Sumi, Jun Adachi, Takayuki Tsukizawa
  • Publication number: 20140126102
    Abstract: An ESD protection device providing highly reliable insulation and having good discharge characteristics is provided. An ESD protection device has opposing first and second discharge electrodes, an auxiliary discharge electrode (18) astride between the first and second discharge electrodes, and an insulating substrate (12) supporting the first and second discharge electrodes and the auxiliary discharge electrode (18). The auxiliary discharge electrode (18) is composed of an assembly of core-shell metal particles (24) that have a core portion (22) mainly composed of a first metal and a shell portion (23) mainly composed of a metal oxide that contains a second metal. The metal particles (24) are substantially completely covered with the shell portion (23) mainly composed of the metal oxide, and this improves the insulation reliability of the device against discharge. Preferably, the metal particles (24) have a bond with each other with a vitreous substance (27) therebetween.
    Type: Application
    Filed: January 14, 2014
    Publication date: May 8, 2014
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Takahiro Sumi, Jun Adachi, Takayuki Tsukizawa, Kumiko Hiehata
  • Patent number: 8704602
    Abstract: A modulation section including a feedback circuit configured to conduct feedback control of an output signal from a voltage controlled oscillator based on an inputted modulation signal, and a feed-forward circuit configured to calibrate the modulation signal and outputting the calibrated modulation signal to the voltage controlled oscillator; a signal output section configured to output, to the modulation section, a predetermined reference signal instead of the modulation signal when a calibration is conducted; and a gain correction section configured to, in a state where the feedback circuit is forming an open loop, calculate a frequency transition amount of the reference signal outputted by the voltage controlled oscillator, and correct a gain used for calibrating the modulation signal at the feed-forward circuit based on the calculated frequency transition amount.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: April 22, 2014
    Assignee: Panasonic Corporation
    Inventors: Kenji Miyanaga, Takayuki Tsukizawa
  • Patent number: 8618904
    Abstract: An ESD protection device includes a ceramic multilayer substrate in which a plurality of ceramic insulating layers are laminated; a first connecting conductor extending through the main surfaces of the insulating layer; a mixture portion extending along a main surface of the insulating layer including the first connecting conductor and connected to the first connecting conductor, the mixture portion including a material dispersed therein, the material including at least one selected from a metal and a semiconductor, a metal and a ceramic, a semiconductor and a ceramic, a semiconductor, and a metal coated with an inorganic material; and a second connecting conductor that has electrical conductivity and is connected to the mixture portion and extends along the main surface of the insulating layer on which the mixture portion is provided.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: December 31, 2013
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takayuki Tsukizawa, Tetsuya Ikeda
  • Publication number: 20130201585
    Abstract: In a method for manufacturing an ESD protection device and an ESD protection device, on sheets defining insulating layers, portions defining a first connection conductor and a second connection conductor and a portion defining a mixed portion are formed, then the sheets are laminated and heated. The mixed portion is formed using a mixed portion formation material containing a cavity formation material and a solid component containing at least one of (i) a metal and a semiconductor, (ii) a metal and ceramic, (iii) a metal, a semiconductor, and ceramic, (iv) a semiconductor and ceramic, (v) a semiconductor, (vi) a metal coated with an inorganic material, (vii) a metal coated with an inorganic material and a semiconductor, (viii) a metal coated with an inorganic material and ceramic, and (ix) a metal coated with an inorganic material, a semiconductor, and ceramic. The cavity formation material disappears during heating.
    Type: Application
    Filed: August 3, 2012
    Publication date: August 8, 2013
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Tetsuya IKEDA, Takayuki TSUKIZAWA
  • Patent number: 8503147
    Abstract: An ESD protection device includes a ceramic multilayer substrate including a plurality of laminated insulating layers, an external electrode, at least one of an in-plane connecting conductor and an interlayer connecting conductor, and a mixture portion. The mixture portion is provided along a principal surface of one of the insulating layers and includes a dispersed material including at least one of metal and semiconductor; metal and ceramic; metal, semiconductor, and ceramic; semiconductor and ceramic; semiconductor; metal coated with an inorganic material; metal coated with an inorganic material and semiconductor; metal coated with an inorganic material and ceramic; and metal coated with an inorganic material, semiconductor, and ceramic. The mixture portion is connected to the external electrode and at least one of the in-plane connecting conductor and the interlayer connecting conductor.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: August 6, 2013
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takayuki Tsukizawa, Tetsuya Ikeda
  • Patent number: 8421582
    Abstract: An ESD protection device includes opposed electrodes in a ceramic base material and a discharge auxiliary electrode in contact with each of the opposed electrodes which is arranged so as to provide a bridge from the opposed electrode on one side to the opposed electrode on the other side, the discharge auxiliary electrode includes metallic particles, semiconductor particles, and a vitreous material, and bonding is provided through the vitreous material between the metallic particles, between the semiconductor particles, and between the metallic particles and the semiconductor particles. The metallic particles have an average particle diameter X of about 1.0 ?m or more, and the relationship between the thickness Y of the discharge auxiliary electrode and the average particle diameter X of the metallic particles satisfies about 0.5?Y/X? about 3.
    Type: Grant
    Filed: February 29, 2012
    Date of Patent: April 16, 2013
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Kumiko Hiehata, Takahiro Sumi, Jun Adachi, Jun Urakawa, Takayuki Tsukizawa
  • Publication number: 20120299693
    Abstract: An ESD protection device includes a ceramic multilayer substrate in which a plurality of ceramic insulating layers are laminated; a first connecting conductor extending through the main surfaces of the insulating layer; a mixture portion extending along a main surface of the insulating layer including the first connecting conductor and connected to the first connecting conductor, the mixture portion including a material dispersed therein, the material including at least one selected from a metal and a semiconductor, a metal and a ceramic, a semiconductor and a ceramic, a semiconductor, and a metal coated with an inorganic material; and a second connecting conductor that has electrical conductivity and is connected to the mixture portion and extends along the main surface of the insulating layer on which the mixture portion is provided.
    Type: Application
    Filed: August 9, 2012
    Publication date: November 29, 2012
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Takayuki TSUKIZAWA, Tetsuya IKEDA
  • Publication number: 20120169452
    Abstract: An ESD protection device includes opposed electrodes in a ceramic base material and a discharge auxiliary electrode in contact with each of the opposed electrodes which is arranged so as to provide a bridge from the opposed electrode on one side to the opposed electrode on the other side, the discharge auxiliary electrode includes metallic particles, semiconductor particles, and a vitreous material, and bonding is provided through the vitreous material between the metallic particles, between the semiconductor particles, and between the metallic particles and the semiconductor particles. The metallic particles have an average particle diameter X of about 1.0 ?m or more, and the relationship between the thickness Y of the discharge auxiliary electrode and the average particle diameter X of the metallic particles satisfies about 0.5?Y/X? about 3.
    Type: Application
    Filed: February 29, 2012
    Publication date: July 5, 2012
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Kumiko HIEHATA, Takahiro SUMI, Jun ADACHI, Jun URAKAWA, Takayuki TSUKIZAWA
  • Publication number: 20120133403
    Abstract: Included are: a modulation section including a feedback circuit configured to conduct feedback control of an output signal from a voltage controlled oscillator based on an inputted modulation signal, and a feed-forward circuit configured to calibrate the modulation signal and outputting the calibrated modulation signal to the voltage controlled oscillator; a signal output section configured to output, to the modulation section, a predetermined reference signal instead of the modulation signal when a calibration is conducted; and a gain correction section configured to, in a state where the feedback circuit is forming an open loop, calculate a frequency transition amount of the reference signal outputted by the voltage controlled oscillator, and correct a gain used for calibrating the modulation signal at the feed-forward circuit based on the calculated frequency transition amount.
    Type: Application
    Filed: June 16, 2010
    Publication date: May 31, 2012
    Inventors: Kenji Miyanaga, Takayuki Tsukizawa
  • Publication number: 20120134059
    Abstract: An ESD protection device includes a ceramic base material, a pair of opposed electrodes provided on a surface of or in the ceramic base material, and a discharge auxiliary electrode film arranged to connect the pair of opposed electrodes, wherein the discharge auxiliary electrode film is composed of a material containing, as its main constituents, metallic particles and glass covering the metallic particles. The discharge auxiliary electrode film is formed by providing an electrode paste containing glass-coated metallic particles that have an approximately 15% rate of increase in weight at about 400° C. for about 2 hours in air, a resin binder, and a solvent so as to connect the pair of opposed electrodes to each other, and then firing at a temperature of about 600° C. or more, higher than a softening point of glass of the glass-coated metallic particles, and not +200° C. higher than the softening point.
    Type: Application
    Filed: February 7, 2012
    Publication date: May 31, 2012
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Takahiro SUMI, Takahiro KITADUME, Jun ADACHI, Takayuki TSUKIZAWA, Masanori OKAMOTO
  • Patent number: 8105453
    Abstract: In a method for producing a multilayer ceramic substrate, a green ceramic laminate includes green conductive patterns arranged on a plurality of ceramic green sheets and portions to be formed into a plurality of multilayer ceramic substrates. Boundary-defining conductive patterns are arranged on the ceramic green sheets and along boundaries of the multilayer ceramic substrates. The boundary-defining conductive patterns have firing shrinkage characteristics that are different from those of the ceramic green sheets. During firing of the green ceramic laminate, cavities adjacent to edges of the boundary-defining conductive patterns are formed. A sintered ceramic laminate is divided at edges passing through the cavities.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: January 31, 2012
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Akiyoshi Kawamura, Takayuki Tsukizawa, Tetsuya Ikeda
  • Patent number: 8076985
    Abstract: Provided is a voltage-controlled oscillator that can hold an oscillation frequency at a desired value when an oscillation frequency changes due to the temperature, without narrowing a variable range of the oscillation frequency, and a PLL circuit, an FLL circuit, and a wireless communication device, which use the voltage-controlled oscillator. A control voltage Vt is applied to a connection point Y between variable capacitors 121 and 122 included in a variable capacitance circuit 120. A control signal Fse1 is applied to a switching element 132 included in a capacitance switching circuit 130. A power-supply voltage Vdd is applied by a control section 170 to a connection point X between inductors 111 and 112 included in an inductor circuit 110. A voltage value of the power-supply voltage Vdd is controlled such that the oscillation frequency of the local oscillation signal is held at a constant regardless of a temperature change.
    Type: Grant
    Filed: March 19, 2010
    Date of Patent: December 13, 2011
    Assignee: Panasonic Corporation
    Inventor: Takayuki Tsukizawa
  • Patent number: 8067995
    Abstract: A voltage controlled oscillator includes first and second variable capacitance circuits 120 and 130, and first and second capacitance switch circuits 140 and 150. A control voltage Vt is fixedly applied to the first variable capacitance circuit 120, and control signals Fsel2 and Fsel3 are fixedly applied to the first and second capacitance switch circuits 140 and 150, respectively. When both of the control signals Fsel2 and Fsel3 are at a low level, the control signal Fsel1 is applied to the second variable capacitance circuit 130. When the control signals Fsel2 and Fsel3 are both not at the low level, the control voltage Vt is applied to the second variable capacitance circuit 130. As a result of this control, a high-frequency variable range is divided into two variable ranges, one based on upper frequencies and the other based on lower frequencies. This enables suppression of a frequency sensitivity without narrowing the high-frequency variable range.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: November 29, 2011
    Assignee: Panasonic Corporation
    Inventor: Takayuki Tsukizawa
  • Publication number: 20110279945
    Abstract: An ESD protection device includes a ceramic multilayer substrate including a plurality of laminated insulating layers, an external electrode, at least one of an in-plane connecting conductor and an interlayer connecting conductor, and a mixture portion. The mixture portion is provided along a principal surface of one of the insulating layers and includes a dispersed material including at least one of metal and semiconductor; metal and ceramic; metal, semiconductor, and ceramic; semiconductor and ceramic; semiconductor; metal coated with an inorganic material; metal coated with an inorganic material and semiconductor; metal coated with an inorganic material and ceramic; and metal coated with an inorganic material, semiconductor, and ceramic. The mixture portion is connected to the external electrode and at least one of the in-plane connecting conductor and the interlayer connecting conductor.
    Type: Application
    Filed: May 13, 2011
    Publication date: November 17, 2011
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventors: Takayuki TSUKIZAWA, Tetsuya IKEDA