Patents by Inventor Masanao Yamaoka

Masanao Yamaoka 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: 20120307572
    Abstract: The semiconductor device makes a comparison between a word-line timing signal for determining a word-line activation time and a reference signal, applies a back-gate bias for enlarging a read margin when the result of the comparison represents a low condition of the read margin, and applies a back-gate bias for enlarging a write margin when the comparison result represents a low condition of the write margin. The reference signal is selected depending on whether to compensate an operating margin fluctuating according to the word-line activation time (or word-line pulse width), or to compensate an operating margin fluctuating according to the process fluctuation (or variation in threshold voltage). By controlling the back-gate biases according to the word-line pulse width, an operating margin fluctuating according to the word-line pulse width, and an operating margin fluctuating owing to the variation in threshold voltage during its fabrication are improved.
    Type: Application
    Filed: August 16, 2012
    Publication date: December 6, 2012
    Inventors: Masanao Yamaoka, Kenichi Osada
  • Patent number: 8294510
    Abstract: There is provided an output stage circuit including such MOSTs (M) that when their gates and sources are respectively set to an equal voltage, subthreshold leakage currents substantially flow between their drains and sources, wherein upon its deactivation, a voltage is applied to the gate of each of the MOSTs (M) in such a manner than a reverse bias is applied between the gate and source of the MOST (M). That is, when the MOST (M) is of a p channel type, a voltage higher than that of a p type source is applied to its gate. When the MOST (M) is of an n channel type, a voltage lower than that of an n type source is applied to its gate. Upon activation of the circuit, the MOST is held in a reverse bias state or controlled to a forward bias state according to an input voltage. A CMOS circuit and a semiconductor device can be realized each of which is small in leakage current even though its threshold voltage is low and which is operated at high speed and with a small voltage amplitude.
    Type: Grant
    Filed: December 11, 2007
    Date of Patent: October 23, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Kiyoo Itoh, Masanao Yamaoka
  • Patent number: 8270230
    Abstract: The semiconductor device makes a comparison between a word-line timing signal for determining a word-line activation time and a reference signal, applies a back-gate bias for enlarging a read margin when the result of the comparison represents a low condition of the read margin, and applies a back-gate bias for enlarging a write margin when the comparison result represents a low condition of the write margin. The reference signal is selected depending on whether to compensate an operating margin fluctuating according to the word-line activation time (or word-line pulse width), or to compensate an operating margin fluctuating according to the process fluctuation (or variation in threshold voltage). By controlling the back-gate biases according to the word-line pulse width, an operating margin fluctuating according to the word-line pulse width, and an operating margin fluctuating owing to the variation in threshold voltage during its fabrication are improved.
    Type: Grant
    Filed: January 19, 2012
    Date of Patent: September 18, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Masanao Yamaoka, Kenichi Osada
  • Patent number: 8264870
    Abstract: When threshold voltages of constituent transistors are reduced in order to operate an SRAM circuit at a low voltage, there is a problem in that a leakage current of the transistors is increased and, as a result, electric power consumption when the SRAM circuit is not operated while storing data is increased. Therefore, there is provided a technique for reducing the leakage current of MOS transistors in SRAM memory cells MC by controlling a potential of a source line ssl of the driver MOS transistors in the memory cells.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: September 11, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Masanao Yamaoka, Kenichi Osada, Kazumasa Yanagisawa
  • Publication number: 20120217620
    Abstract: The need for mediation operation is eliminated by adoption of a connection topology in which a circuit for executing one transmission (TR—00T), and a circuit for executing a plurality of receptions (TR—10R, TR—20R, TR—30R) are connected to one penetration-electrode group (for example, TSVGL—0). In order to implement the connection topology even in the case of piling up a plurality of LSIs one after another, in particular, a programmable memory element for designating respective penetration-electrode ports for use in transmit, or for us in receive, and address allocation of the respective penetration-electrode ports is mounted in stacked LSIs.
    Type: Application
    Filed: May 2, 2012
    Publication date: August 30, 2012
    Inventors: Makoto SAEN, Kenichi Osada, Masanao Yamaoka, Tomonori Sekiguchi
  • Publication number: 20120195110
    Abstract: When threshold voltages of constituent transistors are reduced in order to operate an SRAM circuit at a low voltage, there is a problem in that a leakage current of the transistors is increased and, as a result, electric power consumption when the SRAM circuit is not operated while storing data is increased. Therefore, there is provided a technique for reducing the leakage current of MOS transistors in SRAM memory cells MC by controlling a potential of a source line ssl of the driver MOS transistors in the memory cells.
    Type: Application
    Filed: April 10, 2012
    Publication date: August 2, 2012
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventors: Masanao YAMAOKA, Kenichi OSADA, Kazumasa YANAGISAWA
  • Patent number: 8203868
    Abstract: An object of the present invention is to provide a technique of reducing the power consumption of an entire low power consumption SRAM LSI circuit employing scaled-down transistors and of increasing the stability of read and write operations on the memory cells by reducing the subthreshold leakage current and the leakage current flowing from the drain electrode to the substrate electrode. Another object of the present invention is to provide a technique of preventing an increase in the number of transistors in a memory cell and thereby preventing an increase in the cell area. Still another object of the present invention is to provide a technique of ensuring stable operation of an SRAM memory cell made up of SOI or FD-SOI transistors having a BOX layer by controlling the potentials of the wells under the BOX layers of the drive transistors.
    Type: Grant
    Filed: February 4, 2011
    Date of Patent: June 19, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Masanao Yamaoka, Takayuki Kawahara
  • Publication number: 20120147662
    Abstract: High manufacturing yield is realized and variation in threshold voltage of each MOS transistor in a CMOS·SRAM is compensated. Body bias voltages are applied to wells for MOS transistors of each SRAM memory cell in any active mode of an information holding operation, a write operation and a read operation of an SRAM. Threshold voltages of PMOS and NMOS transistors of the SRAM are first measured. Control information is programmed into control memories according to results of determination. Levels of the body bias voltages are adjusted based on the programs so that variations in the threshold voltages of the MOS transistors of the CMOS·SRAM are controlled to a predetermined error span. Body bias voltage corresponding to a reverse body bias or an extremely shallow forward body bias is applied to a substrate for the MOS transistors with an operating voltage applied to the source of each MOS transistor.
    Type: Application
    Filed: January 13, 2012
    Publication date: June 14, 2012
    Inventors: Masanao YAMAOKA, Kenichi OSADA, Shigenobu KOMATSU
  • Publication number: 20120136596
    Abstract: An object of the present invention is to sufficiently supply power to three-dimensionally stacked LSI chips and to dispose common through vias in chips of different types. Also, another object is to propose a new test method for power-supply through silicon vias.
    Type: Application
    Filed: September 14, 2009
    Publication date: May 31, 2012
    Inventors: Masanao Yamaoka, Kenichi Osada
  • Patent number: 8184463
    Abstract: The need for mediation operation is eliminated by adoption of a connection topology in which a circuit for executing one transmission (TR—00T), and a circuit for executing a plurality of receptions (TR—10R, TR—20R, TR—30R) are connected to one penetration-electrode group (for example, TSVGL—0). In order to implement the connection topology even in the case of piling up a plurality of LSIs one after another, in particular, a programmable memory element for designating respective penetration-electrode ports for use in transmit, or for us in receive, and address allocation of the respective penetration-electrode ports is mounted in stacked LSIs.
    Type: Grant
    Filed: December 13, 2009
    Date of Patent: May 22, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Makoto Saen, Kenichi Osada, Masanao Yamaoka, Tomonori Sekiguchi
  • Publication number: 20120120738
    Abstract: The semiconductor device makes a comparison between a word-line timing signal for determining a word-line activation time and a reference signal, applies a back-gate bias for enlarging a read margin when the result of the comparison represents a low condition of the read margin, and applies a back-gate bias for enlarging a write margin when the comparison result represents a low condition of the write margin. The reference signal is selected depending on whether to compensate an operating margin fluctuating according to the word-line activation time (or word-line pulse width), or to compensate an operating margin fluctuating according to the process fluctuation (or variation in threshold voltage). By controlling the back-gate biases according to the word-line pulse width, an operating margin fluctuating according to the word-line pulse width, and an operating margin fluctuating owing to the variation in threshold voltage during its fabrication are improved.
    Type: Application
    Filed: January 19, 2012
    Publication date: May 17, 2012
    Inventors: Masanao YAMAOKA, Kenichi OSADA
  • Patent number: 8125845
    Abstract: Even when memory capacity of a memory that uses a replica bit-line is made higher, fluctuations of a generating timing of a sense-amplifier enable signal are reduced. A semiconductor integrated circuit device comprises a plurality of word lines, a plurality of bit-lines, a plurality of ordinary memory cells, an access control circuit, a plurality of sense-amplifiers, first and second replica bit-lines, first and second replica memory cells, and first and second logic circuits. The first and second replica memory cells are connected to the first and second replica bit-lines, respectively; inputs of the first and second logic circuits are connected to the first and second replica bit-lines, respectively; a sense-amplifier enable signal is generated from an output of the second logic circuit; and this signal is supplied to a plurality of sense-amplifiers.
    Type: Grant
    Filed: January 14, 2010
    Date of Patent: February 28, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Shigenobu Komatsu, Masanao Yamaoka, Noriaki Maeda, Masao Morimoto, Yasuhisa Shimazaki
  • Patent number: 8125837
    Abstract: The semiconductor device makes a comparison between a word-line timing signal for determining a word-line activation time and a reference signal, applies a back-gate bias for enlarging a read margin when the result of the comparison represents a low condition of the read margin, and applies a back-gate bias for enlarging a write margin when the comparison result represents a low condition of the write margin. The reference signal is selected depending on whether to compensate an operating margin fluctuating according to the word-line activation time (or word-line pulse width), or to compensate an operating margin fluctuating according to the process fluctuation (or variation in threshold voltage). By controlling the back-gate biases according to the word-line pulse width, an operating margin fluctuating according to the word-line pulse width, and an operating margin fluctuating owing to the variation in threshold voltage during its fabrication are improved.
    Type: Grant
    Filed: August 18, 2009
    Date of Patent: February 28, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Masanao Yamaoka, Kenichi Osada
  • Publication number: 20120044775
    Abstract: The invention provides a semiconductor integrated circuit device provided with an SRAM that satisfies the requirements for both the SNM and the write margin with a low supply voltage. The semiconductor integrated circuit device include: multiple static memory cells provided in correspondence with multiple word lines and multiple complimentary bit lines; multiple memory cell power supply lines that each supply an operational voltage to each of the multiple memory cells connected to the multiple complimentary bit lines each; multiple power supply circuits comprised of resistive units that each supply a power supply voltage to the memory cell power supply lines each; and a pre-charge circuit that supplies a pre-charge voltage corresponding to the power supply voltage to the complimentary bit lines, wherein the memory cell power supply lines are made to have coupling capacitances to thereby transmit a write signal on corresponding complimentary bit lines.
    Type: Application
    Filed: October 31, 2011
    Publication date: February 23, 2012
    Inventors: Noriaki Maeda, Yoshihiro Shinozaki, Masanao Yamaoka, Yasuhisa Shimazaki, Masanori Isoda, Koji Nii
  • Patent number: 8107279
    Abstract: High manufacturing yield is realized and variations in threshold voltage of each MOS transistor in a CMOS.SRAM is compensated. Body bias voltages are applied to wells for MOS transistors of each SRAM memory cell in any active mode of an information holding operation, a write operation and a read operation of an SRAM. The threshold voltages of PMOS and NMOS transistors of the SRAM are first measured. Control information is respectively programmed into control memories according to the results of determination. The levels of the body bias voltages are adjusted based on the programs so that variations in the threshold voltages of the MOS transistors of the CMOS.SRAM are controlled to a predetermined error span. A body bias voltage corresponding to a reverse body bias or an extremely shallow forward body bias is applied to a substrate for the MOS transistors with an operating voltage applied to the source of each MOS transistor.
    Type: Grant
    Filed: September 21, 2009
    Date of Patent: January 31, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Masanao Yamaoka, Kenichi Osada, Shigenobu Komatsu
  • Patent number: 8072799
    Abstract: The invention provides a semiconductor integrated circuit device provided with an SRAM that satisfies the requirements for both the SNM and the write margin with a low supply voltage. The semiconductor integrated circuit device include: multiple static memory cells provided in correspondence with multiple word lines and multiple complimentary bit lines; multiple memory cell power supply lines that each supply an operational voltage to each of the multiple memory cells connected to the multiple complimentary bit lines each; multiple power supply circuits comprised of resistive units that each supply a power supply voltage to the memory cell power supply lines each; and a pre-charge circuit that supplies a pre-charge voltage corresponding to the power supply voltage to the complimentary bit lines, wherein the memory cell power supply lines are made to have coupling capacitances to thereby transmit a write signal on corresponding complimentary bit lines.
    Type: Grant
    Filed: March 29, 2010
    Date of Patent: December 6, 2011
    Assignee: Renesas Electronics Corporation
    Inventors: Noriaki Maeda, Yoshihiro Shinozaki, Masanao Yamaoka, Yasuhisa Shimazaki, Masanori Isoda, Koji Nii
  • Publication number: 20110234297
    Abstract: Provided is a control technique of a semiconductor integrated circuit capable by which power on/shut-off of a power shut-off area at an optimum speed in accordance with variations in fabricating devices as suppressing the malfunction of a circuit during operation in the power on/shut-off. A semiconductor integrated circuit includes: an always-on area; a power shut-off area; and a plurality of power-supply switches connected to the power shut-off area for supplying or shutting off the power to the power shut-off area. Further, the semiconductor integrated circuit includes a switch controller for carrying out the power on/shut-off by controlling on/off of the plurality of power-supply switches and changing the transition time of the power on/shut-off in accordance with a performance of each of the semiconductor integrated circuit after fabricating. Further, the semiconductor integrated circuit includes a memory for recording the performance of each of the semiconductor integrated circuit after fabricating.
    Type: Application
    Filed: February 12, 2011
    Publication date: September 29, 2011
    Inventors: Tetsuya FUKUOKA, Yasuhiro Fujimura, Masanao Yamaoka
  • Publication number: 20110221516
    Abstract: Information technology equipment includes a circuit block, a local power source line for supplying a power source to the circuit block, a power source line, and a first transistor which is provided with a source-drain path thereof between the power source line and the local power source line, in which the first transistor is controlled to an OFF state in a first state, and is controlled to an ON state in a second state, and when the first state is shifted to the second state, the first transistor is controlled such that a rate of changing a current flowing in the source-drain path of the first transistor does not exceed a predetermined value.
    Type: Application
    Filed: January 8, 2011
    Publication date: September 15, 2011
    Inventors: Masanao YAMAOKA, Kenichi Osada, Minoru Motoyoshi, Tetsuya Fukuoka
  • Publication number: 20110216579
    Abstract: A logic circuit in a system LSI is provided with a power switch so as to cut off the switch at the time of standby, reducing leakage current. At the same time, an SRAM circuit of the system LSI controls a substrate bias to reduce leakage current.
    Type: Application
    Filed: May 18, 2011
    Publication date: September 8, 2011
    Inventors: MASANAO YAMAOKA, KOICHIRO ISHIBASHI, SHIGEZUMI MATSUI, KENICHI OSADA
  • Patent number: 7995377
    Abstract: An object of the present invention is to provide a technique of reducing the power consumption of an entire low power consumption SRAM LSI circuit employing scaled-down transistors and of increasing the stability of read and write operations on the memory cells by reducing the subthreshold leakage current and the leakage current flowing from the drain electrode to the substrate electrode. Another object of the present invention is to provide a technique of preventing an increase in the number of transistors in a memory cell and thereby preventing an increase in the cell area. Still another object of the present invention is to provide a technique of ensuring stable operation of an SRAM memory cell made up of SOI or FD-SOI transistors having a BOX layer by controlling the potentials of the wells under the BOX layers of the drive transistors.
    Type: Grant
    Filed: November 23, 2009
    Date of Patent: August 9, 2011
    Assignee: Renesas Electronics Corporation
    Inventors: Masanao Yamaoka, Takayuki Kawahara