Patents by Inventor Kazuhiro Tsumura

Kazuhiro Tsumura 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: 20150214836
    Abstract: Provided is a voltage divider circuit having a small area and good accuracy of a division ratio. Among a plurality of resistors of the voltage divider circuit, each of resistors having a large resistance value, that is, resistors (1/4R, 1/2R, 1R, 9R, 10R) having high required accuracy of ratio includes first unit resistors (5A) that have a first resistance value and are connected in series or connected in parallel to each other, and each of resistors having a small resistance value, that is, resistors (1/16R, 1/8R) having low required accuracy of ratio includes second unit resistors (5B) that have a second resistance value smaller than the first resistance value and are connected in parallel to each other.
    Type: Application
    Filed: August 13, 2013
    Publication date: July 30, 2015
    Inventor: Kazuhiro Tsumura
  • Patent number: 9053798
    Abstract: A non-volatile memory circuit is formed of a P-channel MOS transistor and includes a P-channel non-volatile memory element having a floating gate and a control gate capacitively coupled together. A resistor divider has a first resistor and a second resistor for dividing a voltage difference between a power supply voltage and a ground voltage. A divided voltage output of the resistor divider is connected to the control gate. First and second switches are connected in parallel to the respective first and second resistors. The first and second switches are controlled so that a voltage of the control gate is set to a voltage of the divided voltage output which maximizes an electric field between a pinch-off point and a drain point of the P-channel MOS transistor in a writing mode.
    Type: Grant
    Filed: December 5, 2013
    Date of Patent: June 9, 2015
    Assignee: SEIKO INSTRUMENTS INC.
    Inventors: Ayako Kawakami, Kazuhiro Tsumura
  • Patent number: 8963224
    Abstract: Provided is a semiconductor device including, on the same semiconductor substrate, a transistor element, a capacitor, and a resistor. The capacitor is formed on an active region, and the resistor is formed on an element isolation region, both formed of the same polysilicon film. By CMP or etch-back, the surface is ground down while planarizing the surface until a resistor has a desired thickness. Owing to a difference in height between the active region and the element isolation region, a thin resistor and a thick upper electrode of the capacitor are formed to prevent passing through of a contact.
    Type: Grant
    Filed: October 8, 2013
    Date of Patent: February 24, 2015
    Assignee: Seiko Instruments Inc.
    Inventors: Ayako Inoue, Kazuhiro Tsumura
  • Patent number: 8902645
    Abstract: Provided is a semiconductor memory circuit excellent in long-term reliability and reading characteristics and having low current consumption. The semiconductor memory circuit includes: a first inverter; a first non-volatile memory, which is electrically writable; a second inverter; and a second non-volatile memory, the first inverter having an output connected to a source of the first non-volatile memory, the first non-volatile memory having a drain connected to an input of the second inverter, the second inverter having an output connected to a source of the second non-volatile memory, the second non-volatile memory having a drain connected to an input of the first inverter, the drain of the second non-volatile memory serving as an output of the semiconductor memory circuit.
    Type: Grant
    Filed: September 23, 2013
    Date of Patent: December 2, 2014
    Assignee: Seiko Instruments Inc.
    Inventor: Kazuhiro Tsumura
  • Patent number: 8823073
    Abstract: A semiconductor memory element has MOS transistor for writing by a drain-avalanche hot electron. The MOS transistor has a semiconductor substrate, a first semiconductor layer formed on the semiconductor substrate, a floating gate provided on the first semiconductor layer through intermediation of a first insulating film, a channel region formed in a surface of the first semiconductor layer under the floating gate, and source region and a drain region provided on the first semiconductor layer so as to be in contact with the channel region. The channel region has a distribution of at least two kinds of carrier densities provided in at least two portions thereof disposed in parallel along a direction connecting the source region and the drain region.
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: September 2, 2014
    Assignee: Seiko Instruments Inc.
    Inventors: Naoto Kobayashi, Kazuhiro Tsumura
  • Patent number: 8760926
    Abstract: Provided is a memory circuit in which erroneous writing is less likely to occur at the time of power-on. A memory circuit (10) includes: a P-channel non-volatile memory element (15) for writing, to which a voltage is applied between a source and a drain thereof only during writing so as to write data; and an N-channel non-volatile memory element (16) for reading, which has a control gate and a floating gate provided in common to a control gate and a floating gate of the P-channel non-volatile memory element (15) and to which a voltage is applied to a source and a drain thereof only during reading so as to read the data.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: June 24, 2014
    Assignee: Seiko Instruments Inc.
    Inventors: Jun Osanai, Yoshitsugu Hirose, Kazuhiro Tsumura, Ayako Inoue
  • Publication number: 20140160860
    Abstract: A resistor divider including two resistors, which is connected to a control gate of a P-channel non-volatile memory element, and two switch transistors connected in parallel to the two resistors are used to adjust the potential of the control gate so that a potential of a floating gate is set in the vicinity of a threshold of the memory element in writing. In the P-channel non-volatile memory element, because the potential of the floating gate is set in the vicinity of the threshold of the memory element, the electric field between a pinch-off point and a drain becomes stronger so that hot carriers are more likely to be generated. Consequently, the write characteristics are improved, and writing can be performed at a low voltage.
    Type: Application
    Filed: December 5, 2013
    Publication date: June 12, 2014
    Applicant: SEIKO INSTRUMENTS INC.
    Inventors: Ayako KAWAKAMI, Kazuhiro TSUMURA
  • Publication number: 20140085987
    Abstract: Provided is a semiconductor memory circuit excellent in long-term reliability and reading characteristics and having low current consumption. The semiconductor memory circuit includes: a first inverter; a first non-volatile memory, which is electrically writable; a second inverter; and a second non-volatile memory, the first inverter having an output connected to a source of the first non-volatile memory, the first non-volatile memory having a drain connected to an input of the second inverter, the second inverter having an output connected to a source of the second non-volatile memory, the second non-volatile memory having a drain connected to an input of the first inverter, the drain of the second non-volatile memory serving as an output of the semiconductor memory circuit.
    Type: Application
    Filed: September 23, 2013
    Publication date: March 27, 2014
    Applicant: SEIKO INSTRUMENTS INC.
    Inventor: Kazuhiro TSUMURA
  • Patent number: 8669156
    Abstract: Provided is a method of manufacturing a semiconductor circuit device including a MOS transistor and a capacitor element in which a gate electrode of a MOS transistor is formed of a first polysilicon film, a capacitor is formed of the first polysilicon film, a capacitor film, and a second polysilicon film, reduction in resistance of a normally-off transistor and reduction in resistance of a lower electrode of the capacitor are simultaneously performed, and reduction in resistance of an N-type MOS transistor and reduction in resistance of an upper electrode of the capacitor are simultaneously performed.
    Type: Grant
    Filed: March 11, 2011
    Date of Patent: March 11, 2014
    Assignee: Seiko Instruments Inc.
    Inventor: Kazuhiro Tsumura
  • Publication number: 20140035016
    Abstract: Provided is a semiconductor device including, on the same semiconductor substrate, a transistor element, a capacitor, and a resistor. The capacitor is formed on an active region, and the resistor is formed on an element isolation region, both formed of the same polysilicon film. By CMP or etch-back, the surface is ground down while planarizing the surface until a resistor has a desired thickness. Owing to a difference in height between the active region and the element isolation region, a thin resistor and a thick upper electrode of the capacitor are formed to prevent passing through of a contact.
    Type: Application
    Filed: October 8, 2013
    Publication date: February 6, 2014
    Applicant: SEIKO INSTRUMENTS INC.
    Inventors: Ayako INOUE, Kazuhiro TSUMURA
  • Patent number: 8581316
    Abstract: Provided is a semiconductor device including, on the same semiconductor substrate, a transistor element, a capacitor, and a resistor. The capacitor is formed on an active region, and the resistor is formed on an element isolation region, both formed of the same polysilicon film. By CMP or etch-back, the surface is ground down while planarizing the surface until a resistor has a desired thickness. Owing to a difference in height between the active region and the element isolation region, a thin resistor and a thick upper electrode of the capacitor are formed to prevent passing through of a contact.
    Type: Grant
    Filed: March 1, 2012
    Date of Patent: November 12, 2013
    Assignee: Seiko Instruments Inc.
    Inventors: Ayako Inoue, Kazuhiro Tsumura
  • Publication number: 20130082317
    Abstract: A semiconductor memory element for writing by a drain-avalanche hot electron includes a MOS transistor having a first semiconductor layer of a second conductivity type formed on a semiconductor substrate of a first conductivity type; a floating gate provided on the first semiconductor layer through intermediation of an insulating film; a channel region formed in a surface of the first semiconductor layer under the floating gate; and a source region and a drain region of the first conductivity type provided on the first semiconductor layer so as to be in contact with the channel region in which the channel region has a distribution of at least two kinds of carrier densities.
    Type: Application
    Filed: September 27, 2012
    Publication date: April 4, 2013
    Inventors: Naoto KOBAYASHI, Kazuhiro TSUMURA
  • Publication number: 20130016563
    Abstract: Provided is a memory circuit in which erroneous writing is less likely to occur at the time of power-on. A memory circuit (10) includes: a P-channel non-volatile memory element (15) for writing, to which a voltage is applied between a source and a drain thereof only during writing so as to write data; and an N-channel non-volatile memory element (16) for reading, which has a control gate and a floating gate provided in common to a control gate and a floating gate of the P-channel non-volatile memory element (15) and to which a voltage is applied to a source and a drain thereof only during reading so as to read the data.
    Type: Application
    Filed: June 27, 2012
    Publication date: January 17, 2013
    Inventors: Jun OSANAI, Yoshitsugu Hirose, Kazuhiro Tsumura, Ayake Inoue
  • Patent number: 8294422
    Abstract: A protection circuit device for a battery having secondary batteries connected in series. A reference voltage circuit generates a reference voltage and a voltage detection circuit for detecting a voltage of one of the secondary batteries and comparing the detected voltage with the reference voltage generated by the reference voltage circuit to thereby detect an over-charge state and an over-discharge state of the one of the secondary batteries. Each of the reference voltage circuit and the voltage detection circuit has a power supply terminal connected to a positive electrode of the one of the secondary batteries and has a ground terminal connected to a negative electrode of the one of the secondary batteries. A withstand voltage of elements forming the reference voltage circuit and the voltage detection circuit is set to be lower than an overall voltage of the secondary batteries.
    Type: Grant
    Filed: February 12, 2010
    Date of Patent: October 23, 2012
    Assignee: Seiko Instruments Inc.
    Inventor: Kazuhiro Tsumura
  • Patent number: 8274830
    Abstract: A non-volatile semiconductor memory circuit capable of improving data retention characteristics and decreasing an area thereof comprises a constant current circuit and a non-volatile memory cell connected in series. A connection point between the constant current source and the non-volatile memory cell is selected to be an output to thereby enable writing, in a reading mode or a retention mode, in the non-volatile memory cell which is in a write state. The non-volatile semiconductor memory circuit includes a power supply for data reading and retaining and a power supply for data rewriting which are provided independently, and a transistor connected between the output and the power supply for data rewriting, in which the transistor is brought into conduction state when data is rewritten.
    Type: Grant
    Filed: August 11, 2009
    Date of Patent: September 25, 2012
    Assignee: Seiko Instruments Inc.
    Inventor: Kazuhiro Tsumura
  • Publication number: 20120228686
    Abstract: Provided is a semiconductor device including, on the same semiconductor substrate, a transistor element, a capacitor, and a resistor. The capacitor is formed on an active region, and the resistor is formed on an element isolation region, both formed of the same polysilicon film. By CMP or etch-back, the surface is ground down while planarizing the surface until a resistor has a desired thickness. Owing to a difference in height between the active region and the element isolation region, a thin resistor and a thick upper electrode of the capacitor are formed to prevent passing through of a contact.
    Type: Application
    Filed: March 1, 2012
    Publication date: September 13, 2012
    Inventors: Ayako INOUE, Kazuhiro Tsumura
  • Patent number: 8259516
    Abstract: Provided is a memory circuit including: memory cells (A) arranged in columns and rows; memory cells (B) each provided for each of the rows for storing information indicative of whether writing into the memory cells (A) of the each of the rows has been completed or not; and a circuit for selecting one of the rows by utilizing the information stored in the memory cells (B). The memory circuit writes information into the memory cell (B) upon completion of writing into the memory cells (A) of a given one of the rows. By utilizing a change in the information stored in the memory cell (B), the given one of the rows is switched from a selected state to a non-selected state, and a next row is switched from the non-selected state to the selected state so that writing is enabled. The operation is repeated to thereby sequentially select a row to be written.
    Type: Grant
    Filed: February 5, 2010
    Date of Patent: September 4, 2012
    Assignee: Seiko Instruments Inc.
    Inventor: Kazuhiro Tsumura
  • Patent number: 8021951
    Abstract: Provided is a semiconductor device including: a silicon substrate; at least two trenches spaced apart from each other, being in parallel with each other, and being formed by vertically etching the silicon substrate from a surface thereof; an electrically insulating film for burying therein at least bottom surfaces of the trenches; a base region formed in a region of the silicon substrate located between the two trenches; and an emitter region and a collector region formed on portions of side surfaces of the trenches, respectively, the portions of the sides located above the insulating film and formed in the base region.
    Type: Grant
    Filed: August 25, 2010
    Date of Patent: September 20, 2011
    Assignee: Seiko Instruments Inc.
    Inventor: Kazuhiro Tsumura
  • Publication number: 20110223730
    Abstract: Provided is a method of manufacturing a semiconductor circuit device including a MOS transistor and a capacitor element in which a gate electrode of a MOS transistor is formed of a first polysilicon film, a capacitor is formed of the first polysilicon film, a capacitor film, and a second polysilicon film, reduction in resistance of a normally-off transistor and reduction in resistance of a lower electrode of the capacitor are simultaneously performed, and reduction in resistance of an N-type MOS transistor and reduction in resistance of an upper electrode of the capacitor are simultaneously performed.
    Type: Application
    Filed: March 11, 2011
    Publication date: September 15, 2011
    Inventor: Kazuhiro Tsumura
  • Patent number: 7902633
    Abstract: Provided is a semiconductor device including: a silicon substrate; at least two trenches spaced apart from each other, being in parallel with each other, and being formed by vertically etching the silicon substrate from a surface thereof; an electrically insulating film for burying therein at least bottom surfaces of the trenches; a base region formed in a region of the silicon substrate located between the two trenches; and an emitter region and a collector region formed on portions of side surfaces of the trenches, respectively, the portions of the sides located above the insulating film and formed in the base region.
    Type: Grant
    Filed: May 21, 2007
    Date of Patent: March 8, 2011
    Assignee: Seiko Instruments Inc.
    Inventor: Kazuhiro Tsumura