Patents by Inventor Junichi Niitsuma

Junichi Niitsuma 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: 9021289
    Abstract: In a power estimator, a power coefficient-calculating section acquires an average value of the number of signal changes per unit time in each circuit range to thereby calculate a power coefficient for each circuit range or calculate a power coefficient for each circuit range when the average value of the number of signal changes per unit time is equal to 1, a correction coefficient-calculating section calculates a ratio of an average value of the number of signal changes per unit time at signal lines included in the circuit range to an average value of the number of signal changes per unit time at observing points designated in the circuit range, as a correction coefficient, and a power value-calculating section calculates a power value for each circuit range based on the correction coefficient and the power coefficient calculated for each circuit range.
    Type: Grant
    Filed: October 14, 2011
    Date of Patent: April 28, 2015
    Assignees: Fujitsu Limited, Fujitsu Semiconductor Limited
    Inventors: Takayuki Sasaki, Hirohisa Kotegawa, Takashi Tokue, Shigeru Satoh, Tatsuro Miyakawa, Ryuji Fujita, Junichi Niitsuma
  • Publication number: 20120095737
    Abstract: In a power estimator, a power coefficient-calculating section acquires an average value of the number of signal changes per unit time in each circuit range to thereby calculate a power coefficient for each circuit range or calculate a power coefficient for each circuit range when the average value of the number of signal changes per unit time is equal to 1, a correction coefficient-calculating section calculates a ratio of an average value of the number of signal changes per unit time at signal lines included in the circuit range to an average value of the number of signal changes per unit time at observing points designated in the circuit range, as a correction coefficient, and a power value-calculating section calculates a power value for each circuit range based on the correction coefficient and the power coefficient calculated for each circuit range.
    Type: Application
    Filed: October 14, 2011
    Publication date: April 19, 2012
    Applicants: FUJITSU SEMICONDUCTOR LIMITED, FUJITSU LIMITED
    Inventors: Takayuki SASAKI, Hirohisa KOTEGAWA, Takashi TOKUE, Shigeru SATOH, Tatsuro MIYAKAWA, Ryuji FUJITA, Junichi NIITSUMA
  • Patent number: 8095354
    Abstract: As a program tool of the embodiment estimating the peak of power consumption, primary processing is performed in which logic simulation is executed in a first time period to extract operation data of a gated clock for every predetermined section within the first time period, e.g. operation waveform data or data on the number of operations. Then, a narrowed section, which is composed of one or more sections and in which the switching activity per unit time is higher compared to other sections, is discovered, the switching activity being obtained from the operation data, and this narrowed section is taken as a second time period. Then, secondary processing is performed in which logic simulation is executed in the second time period to extract signal waveform data for every clock cycle and obtain power consumption data corresponding to the clock cycles from the extracted signal waveform data.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: January 10, 2012
    Assignee: Fujitsu Limited
    Inventors: Kazuhide Tamaki, Ryuji Fujita, Junichi Niitsuma, Takayuki Sasaki
  • Patent number: 7900172
    Abstract: Disclosed is a power consumption analysis method capable of reducing an analysis time of power consumption. The method is performed on a design circuit having a characteristic signal for specifying an operating mode of a circuit block and the method comprises the steps of: measuring an operating rate of the characteristic signal in each unit analysis interval for analyzing the power consumption; determining, based on measurement results of the operating rate of the characteristic signal, whether to measure the operating rate of the circuit block whose operating mode is specified by the characteristic signal; and measuring the operating rate of the circuit block only when determined to measure the operating rate of the circuit block.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: March 1, 2011
    Assignee: Fujitsu Limited
    Inventors: Junichi Niitsuma, Ryuji Fujita, Kazuhide Tamaki, Takayuki Sasaki
  • Patent number: 7882458
    Abstract: A power consumption analyzing method, to be implemented by a computer, is for a circuit developing procedure that makes a logic design of the circuit in an RTL design stage and inserts a gated clock with respect to the circuit in a subsequent logic synthesis stage.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: February 1, 2011
    Assignee: Fujitsu Limited
    Inventors: Kazuhide Tamaki, Ryuji Fujita, Junichi Niitsuma, Takayuki Sasaki
  • Publication number: 20080177488
    Abstract: Disclosed is a power consumption analysis method capable of reducing an analysis time of power consumption. The method is performed on a design circuit having a characteristic signal for specifying an operating mode of a circuit block and the method comprises the steps of: measuring an operating rate of the characteristic signal in each unit analysis interval for analyzing the power consumption; determining, based on measurement results of the operating rate of the characteristic signal, whether to measure the operating rate of the circuit block whose operating mode is specified by the characteristic signal; and measuring the operating rate of the circuit block only when determined to measure the operating rate of the circuit block.
    Type: Application
    Filed: March 28, 2008
    Publication date: July 24, 2008
    Inventors: Junichi Niitsuma, Ryuji Fujita, Kazuhide Tamaki, Takayuki Sasaki
  • Publication number: 20080127001
    Abstract: A power consumption analyzing method, to be implemented by a computer, is for a circuit developing procedure that makes a logic design of the circuit in an RTL design stage and inserts a gated clock with respect to the circuit in a subsequent logic synthesis stage.
    Type: Application
    Filed: October 17, 2007
    Publication date: May 29, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Kazuhide Tamaki, Ryuji Fujita, Junichi Niitsuma, Takayuki Sasaki
  • Publication number: 20080059923
    Abstract: A logic simulation is executed for a first netlist, activity rate data is determined for the gated clock buffer, the power consumption is calculated from the activity rate data. Thereafter, given a modified second netlist having at least a portion of the cells of the first netlist, activity rate data for the second netlist is determined from activity rate data for the first netlist, based on the correspondence relation between the gated clock buffers for the first and second netlists. The power consumption is calculated from the activity rate data thus determined. By this means, the power consumption can be estimated for the second netlist without again performing a logic simulation.
    Type: Application
    Filed: September 4, 2007
    Publication date: March 6, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Takayuki Sasaki, Junichi Niitsuma, Kazuhide Tamaki, Ryuji Fujita
  • Publication number: 20070011440
    Abstract: A processor for performing processing based on an instruction code stored in an instruction memory. In the instruction code, a plurality of operations corresponding to a common calculation pattern are represented by a common instruction set designating logical registers. A register-assignment control unit includes a plurality of register-map tables, and determines one or more physical registers assigned to the logical registers designated by the common instruction set, by use of one of the register-map tables which is designated when the common instruction set is called, where each of the register-map tables stores information indicating assignment of one or more physical registers to logical registers.
    Type: Application
    Filed: February 22, 2006
    Publication date: January 11, 2007
    Inventor: Junichi Niitsuma