Patents by Inventor Masahiro Numa

Masahiro Numa 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).

  • Comparator circuit provided with differential amplifier making logical judgment by comparing input voltage with reference voltage
    Patent number: 8330499
    Abstract: In a comparator circuit having a differential amplifier, which makes a logical judgment by comparing an input voltage with a reference voltage, generates and outputs a resulting output voltage thereof, a current source generates and supplies a bias current of a predetermined minute current to the differential amplifier, and a first inverter circuit inverts a differential voltage from the differential amplifier. An adaptive bias current generator circuit detects the bias current of the current source, and a through current of the first inverter circuit. The adaptive bias current generator circuit generates and supplies an adaptive bias current for executing adaptive bias current control to the differential amplifier to allow the differential amplifier to operate with the bias current upon no logical judgment, and to allow the differential amplifier to operate by using the adaptive bias current obtained by increasing the bias current upon logical judgment.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: December 11, 2012
    Assignee: Semiconductor Technology Academic Research Center
    Inventors: Tetsuya Hirose, Keishi Tsubaki, Masahiro Numa
  • COMPARATOR CIRCUIT PROVIDED WITH DIFFERENTIAL AMPLIFIER MAKING LOGICAL JUDGMENT BY COMPARING INPUT VOLTAGE WITH REFERENCE VOLTAGE
    Publication number: 20110210762
    Abstract: In a comparator circuit having a differential amplifier, which makes a logical judgment by comparing an input voltage with a reference voltage, generates and outputs a resulting output voltage thereof, a current source generates and supplies a bias current of a predetermined minute current to the differential amplifier, and a first inverter circuit inverts a differential voltage from the differential amplifier. An adaptive bias current generator circuit detects the bias current of the current source, and a through current of the first inverter circuit. The adaptive bias current generator circuit generates and supplies an adaptive bias current for executing adaptive bias current control to the differential amplifier to allow the differential amplifier to operate with the bias current upon no logical judgment, and to allow the differential amplifier to operate by using the adaptive bias current obtained by increasing the bias current upon logical judgment.
    Type: Application
    Filed: February 28, 2011
    Publication date: September 1, 2011
    Inventors: Tetsuya HIROSE, Keishi TSUBAKI, Masahiro NUMA