Patents by Inventor Yasuto Igarashi

Yasuto Igarashi 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: 20150220095
    Abstract: A semiconductor integrated circuit includes a plurality of output transistors each controlling the magnitude of an output voltage relative to the magnitude of a load current according to a control value indicated by an impedance control signal applied to a control terminal, a voltage monitor circuit outputting an output voltage monitor value indicating a voltage value of the output voltage, and a control circuit controlling the magnitude of the control value according to the magnitude of an error value between a reference voltage indicating a target value of the output voltage and the output voltage monitor value, and controls based on the control value whether any of such transistors be brought to a conducting state. The control circuit increases a change step of the control value relative to the error value during a predetermined period according to prenotification signals for notifying a change of the load current in advance.
    Type: Application
    Filed: April 13, 2015
    Publication date: August 6, 2015
    Inventors: Masafumi ONOUCHI, Kazuo OTSUGA, Yasuto IGARASHI, Sadayuki MORITA, Koichiro ISHIBASHI, Kazumasa YANAGISAWA
  • Patent number: 9030176
    Abstract: A semiconductor integrated circuit includes a plurality of output transistors each controlling the magnitude of an output voltage relative to the magnitude of a load current according to a control value indicated by an impedance control signal applied to a control terminal, a voltage monitor circuit outputting an output voltage monitor value indicating a voltage value of the output voltage, and a control circuit controlling the magnitude of the control value according to the magnitude of an error value between a reference voltage indicating a target value of the output voltage and the output voltage monitor value, and controls based on the control value whether any of such transistors be brought to a conducting state. The control circuit increases a change step of the control value relative to the error value during a predetermined period according to prenotification signals for notifying a change of the load current in advance.
    Type: Grant
    Filed: November 12, 2012
    Date of Patent: May 12, 2015
    Assignee: Renesas Electronics Corporation
    Inventors: Masafumi Onouchi, Kazuo Otsuga, Yasuto Igarashi, Sadayuki Morita, Koichiro Ishibashi, Kazumasa Yanagisawa
  • Patent number: 8730703
    Abstract: Efficient reduction in power consumption is achieved by combinational implementation of a power cutoff circuit technique using power supply switch control and a DVFS technique for low power consumption. A power supply switch section fed with power supply voltage, a circuit block in which a power cutoff is performed by the power supply switch section, and a level shifter are formed in a DEEP-NWELL region formed over a semiconductor substrate. Another power supply switch section fed with another power supply voltage, a circuit block in which a power cutoff is performed by the power supply switch section, and a level shifter are formed in another DEEP-NWELL region formed over the semiconductor substrate. In this arrangement, there arises no possibility of short-circuiting between different power supplies via each DEEP-NWELL region formed over the semiconductor substrate.
    Type: Grant
    Filed: January 24, 2013
    Date of Patent: May 20, 2014
    Assignee: Renesas Electronics Corporation
    Inventors: Kazuki Fukuoka, Yasuto Igarashi, Ryo Mori, Yoshihiko Yasu, Toshio Sasaki
  • Patent number: 8482038
    Abstract: A technique which reduces the influence of external noise such as crosstalk noise in a semiconductor device to prevent a circuit from malfunctioning. A true signal wire and a bar signal wire which are susceptible to noise and part of an input signal line to a level shifter circuit, and shield wires for shielding these signal wires are laid on an I/O cell. Such I/O cells are placed side by side to complete a true signal wire connection and a bar signal wire connection. These wires are arranged in a way to pass over a plurality of I/O cells and are parallel to each other or multilayered.
    Type: Grant
    Filed: July 10, 2012
    Date of Patent: July 9, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Takayuki Sasaki, Yasuto Igarashi, Naozumi Morino
  • Patent number: 8379425
    Abstract: Efficient reduction in power consumption is achieved by combinational implementation of a power cutoff circuit technique using power supply switch control and a DVFS technique for low power consumption. A power supply switch section fed with power supply voltage, a circuit block in which a power cutoff is performed by the power supply switch section, and a level shifter are formed in a DEEP-NWELL region formed over a semiconductor substrate. Another power supply switch section fed with another power supply voltage, a circuit block in which a power cutoff is performed by the power supply switch section, and a level shifter are formed in another DEEP-NWELL region formed over the semiconductor substrate. In this arrangement, there arises no possibility of short-circuiting between different power supplies via each DEEP-NWELL region formed over the semiconductor substrate.
    Type: Grant
    Filed: February 26, 2010
    Date of Patent: February 19, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Kazuki Fukuoka, Yasuto Igarashi, Ryo Mori, Yoshihiko Yasu, Toshio Sasaki
  • Publication number: 20120280741
    Abstract: A technique which reduces the influence of external noise such as crosstalk noise in a semiconductor device to prevent a circuit from malfunctioning. A true signal wire and a bar signal wire which are susceptible to noise and part of an input signal line to a level shifter circuit, and shield wires for shielding these signal wires are laid on an I/O cell. Such I/O cells are placed side by side to complete a true signal wire connection and a bar signal wire connection. These wires are arranged in a way to pass over a plurality of I/O cells and are parallel to each other or multilayered.
    Type: Application
    Filed: July 10, 2012
    Publication date: November 8, 2012
    Inventors: Takayuki SASAKI, Yasuto Igarashi, Naozumi Morino
  • Patent number: 8242541
    Abstract: A technique which reduces the influence of external noise such as crosstalk noise in a semiconductor device to prevent a circuit from malfunctioning. A true signal wire and a bar signal wire which are susceptible to noise and part of an input signal line to a level shifter circuit, and shield wires for shielding these signal wires are laid on an I/O cell. Such I/O cells are placed side by side to complete a true signal wire connection and a bar signal wire connection. These wires are arranged in a way to pass over a plurality of I/O cells and are parallel to each other or multilayered.
    Type: Grant
    Filed: January 9, 2007
    Date of Patent: August 14, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Takayuki Sasaki, Yasuto Igarashi, Naozumi Morino
  • Publication number: 20110068826
    Abstract: A semiconductor integrated circuit device enhanced in design efficiency while achieving multi-functionalization and power saving is to be provided. The semiconductor integrated circuit device has first through third circuit blocks, and is placed in a first power supply state in which the operation of internal circuits in the first circuit block is guaranteed in accordance with an instruction from the third circuit block or a second power supply state in which the operation of the internal circuits is not guaranteed.
    Type: Application
    Filed: December 1, 2010
    Publication date: March 24, 2011
    Inventors: Yuri AZUMA, Yoshihiko Yasu, Yasuto Igarashi, Takashi Kuraishi, Kazumasa Yanagisawa
  • Patent number: 7855593
    Abstract: A semiconductor integrated circuit device enhanced in design efficiency while achieving multi-functionalization and power saving is to be provided. The semiconductor integrated circuit device has first through third circuit blocks, and is placed in a first power supply state in which the operation of internal circuits in the first circuit block is guaranteed in accordance with an instruction from the third circuit block or a second power supply state in which the operation of the internal circuits is not guaranteed.
    Type: Grant
    Filed: July 6, 2009
    Date of Patent: December 21, 2010
    Assignee: Renesas Electronics Corporation
    Inventors: Yuri Azuma, Yoshihiko Yasu, Yasuto Igarashi, Takashi Kuraishi, Kazumasa Yanagisawa
  • Publication number: 20100219800
    Abstract: Efficient reduction in power consumption is achieved by combinational implementation of a power cutoff circuit technique using power supply switch control and a DVFS technique for low power consumption. A power supply switch section fed with power supply voltage, a circuit block in which a power cutoff is performed by the power supply switch section, and a level shifter are formed in a DEEP-NWELL region formed over a semiconductor substrate. Another power supply switch section fed with another power supply voltage, a circuit block in which a power cutoff is performed by the power supply switch section, and a level shifter are formed in another DEEP-NWELL region formed over the semiconductor substrate. In this arrangement, there arises no possibility of short-circuiting between different power supplies via each DEEP-NWELL region formed over the semiconductor substrate.
    Type: Application
    Filed: February 26, 2010
    Publication date: September 2, 2010
    Inventors: Kazuki FUKUOKA, Yasuto Igarashi, Ryo Mori, Yoshihiko Yasu, Toshio Sasaki
  • Publication number: 20090267686
    Abstract: A semiconductor integrated circuit device enhanced in design efficiency while achieving multi-functionalization and power saving is to be provided. The semiconductor integrated circuit device has first through third circuit blocks, and is placed in a first power supply state in which the operation of internal circuits in the first circuit block is guaranteed in accordance with an instruction from the third circuit block or a second power supply state in which the operation of the internal circuits is not guaranteed.
    Type: Application
    Filed: July 6, 2009
    Publication date: October 29, 2009
    Inventors: Yuri Azuma, Yoshihiko Yasu, Yasuto Igarashi, Takashi Kuraishi, Kazumasa Yanagisawa
  • Publication number: 20080218224
    Abstract: The present invention is directed to assure an initial state of a circuit until a power supply voltage is stabilized at the time of power-on and to prevent an output circuit of an external input/output buffer circuit from performing erroneous operation at the time of setting a predetermined register value or the like to an initial value. A power supply detecting circuit outputs a power supply voltage detection signal indicating that a power supply voltage supplied from the outside enters a predetermined state. A power on reset circuit receives the power supply voltage detection signal, instructs an initial setting operation of the internal circuit at a predetermined timing and, in response to completion of the initial setting operation of the internal circuit, changes an external input/output buffer circuit from a high impedance state to an operable state. Consequently, when the external input/output buffer circuit becomes operable, the initial setting of the internal circuit has already completed.
    Type: Application
    Filed: May 13, 2008
    Publication date: September 11, 2008
    Inventors: Naozumi Morino, Takahiro Irita, Yasuto Igarashi
  • Patent number: 7411267
    Abstract: The invention provides a semiconductor integrated circuit device with improved designing efficiency while achieving higher functions. An inner circuit is surrounded by a plurality of cells in which a first switch element for connecting a power supply voltage line or a ground voltage supply line to a power supply line of an internal circuit is disposed below power supply lines extending in a first and second directions, and the power lines are connected together.
    Type: Grant
    Filed: February 3, 2005
    Date of Patent: August 12, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Kentaro Yamawaki, Yoshihiko Yasu, Yasuto Igarashi, Takashi Kuraishi, Kazumasa Yanagisawa
  • Patent number: 7378887
    Abstract: The present invention is directed to assure an initial state of a circuit until a power supply voltage is stabilized at the time of power-on and to prevent an output circuit of an external input/output buffer circuit from performing erroneous operation at the time of setting a predetermined register value or the like to an initial value. A power supply detecting circuit outputs a power supply voltage detection signal indicating that a power supply voltage supplied from the outside enters a predetermined state. A power on reset circuit receives the power supply voltage detection signal, instructs an initial setting operation of the internal circuit at a predetermined timing and, in response to completion of the initial setting operation of the internal circuit, changes an external input/output buffer circuit from a high impedance state to an operable state. Consequently, when the external input/output buffer circuit becomes operable, the initial setting of the internal circuit has already completed.
    Type: Grant
    Filed: July 31, 2006
    Date of Patent: May 27, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Naozumi Morino, Takahiro Irita, Yasuto Igarashi
  • Publication number: 20070206781
    Abstract: A technique which reduces the influence of external noise such as crosstalk noise in a semiconductor device to prevent a circuit from malfunctioning. A true signal wire and a bar signal wire which are susceptible to noise and part of an input signal line to a level shifter circuit, and shield wires for shielding these signal wires are laid on an I/O cell. Such I/O cells are placed side by side to complete a true signal wire connection and a bar signal wire connection. These wires are arranged in a way to pass over a plurality of I/O cells and are parallel to each other or multilayered.
    Type: Application
    Filed: January 9, 2007
    Publication date: September 6, 2007
    Inventors: Takayuki Sasaki, Yasuto Igarashi, Naozumi Morino
  • Publication number: 20070046342
    Abstract: The present invention is directed to assure an initial state of a circuit until a power supply voltage is stabilized at the time of power-on and to prevent an output circuit of an external input/output buffer circuit from performing erroneous operation at the time of setting a predetermined register value or the like to an initial value. A power supply detecting circuit outputs a power supply voltage detection signal indicating that a power supply voltage supplied from the outside enters a predetermined state. A power on reset circuit receives the power supply voltage detection signal, instructs an initial setting operation of the internal circuit at a predetermined timing and, in response to completion of the initial setting operation of the internal circuit, changes an external input/output buffer circuit from a high impedance state to an operable state. Consequently, when the external input/output buffer circuit becomes operable, the initial setting of the internal circuit has already completed.
    Type: Application
    Filed: July 31, 2006
    Publication date: March 1, 2007
    Inventors: Naozumi Morino, Takahiro Irita, Yasuto Igarashi
  • Publication number: 20050232053
    Abstract: A semiconductor integrated circuit device enhanced in design efficiency while achieving multi-functionalization and power saving is to be provided.
    Type: Application
    Filed: April 20, 2005
    Publication date: October 20, 2005
    Inventors: Yuri Azuma, Yoshihiko Yasu, Yasuto Igarashi, Takashi Kuraishi, Kazumasa Yanagisawa
  • Publication number: 20050218959
    Abstract: The invention provides a semiconductor integrated circuit device with improved designing efficiency while achieving higher functions.
    Type: Application
    Filed: February 3, 2005
    Publication date: October 6, 2005
    Inventors: Kentaro Yamawaki, Yoshihiko Yasu, Yasuto Igarashi, Takashi Kuraishi, Kazumasa Yanagisawa
  • Patent number: 6301184
    Abstract: A DRAM module is applied to the system LSI which is provided with a standby mode for suppressing the whole operation thereof and an operation standby mode which permits at least the DRAM module to operate but suppresses the operation of other circuits. The above-mentioned modes as well as a substrate bias control technology are applied to the CMOS system LSI that operates on a low voltage. The system LSI is controlled to hold or not to hold data, enabling a memory of a large capacity to be mounted and consuming a sufficiently decreased amount of electric power.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: October 9, 2001
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Toshio Sasaki, Yoshihiko Yasu, Kazumasa Yanagisawa, Yuji Tanaka, Toshiaki Takahira, Yasuto Igarashi, Mariko Ohtsuka, Yasunobu Aoki