Patents by Inventor Spyridon Vlassis

Spyridon Vlassis 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: 7546332
    Abstract: Apparatus and methods for implementation of mathematical functions apparatus providing both speed and accuracy. Disclosed are specific circuits and methods of operation thereof that may be used for the purpose of implementing an exponential function, a squaring function, and a cubic function, using the same basic circuit. By applying a desired weighting function on a current source, an output current provides a value that corresponds exactly to the desired mathematical functions at discrete points, and closely tracks values in between the discrete points. The precision is defined by the selection of a voltage reference for the circuit. Various embodiments are disclosed, as well as embodiments implementing other exemplary functions.
    Type: Grant
    Filed: November 9, 2005
    Date of Patent: June 9, 2009
    Assignee: Theta Microelectronics, Inc.
    Inventor: Spyridon Vlassis
  • Patent number: 7499687
    Abstract: In many circuits, including those operating in radio frequency (RF), there is commonly a need to perform DC offset cancellation. The DC offset is an error in an output signal in respect to the input that may cause a circuit to enter into undesirable or non-tolerable conditions of operation. While in most cases a static solution is provided the use of an analog loop may be inappropriate because of the adverse impact on speed. By adding a fast feedback loop finely impacting the adjustment of an amplifier, both the initial calibration is achieved as well as a recalibration of the system.
    Type: Grant
    Filed: November 9, 2005
    Date of Patent: March 3, 2009
    Assignee: Theta Microelectronics, Inc.
    Inventors: Konstantinos Papathanasiou, Spyridon Vlassis
  • Publication number: 20060106904
    Abstract: Apparatus and methods for implementation of mathematical functions apparatus providing both speed and accuracy. Disclosed are specific circuits and methods of operation thereof that may be used for the purpose of implementing an exponential function, a squaring function, and a cubic function, using the same basic circuit. By applying a desired weighting function on a current source, an output current provides a value that corresponds exactly to the desired mathematical functions at discrete points, and closely tracks values in between the discrete points. The precision is defined by the selection of a voltage reference for the circuit. Various embodiments are disclosed, as well as embodiments implementing other exemplary functions.
    Type: Application
    Filed: November 9, 2005
    Publication date: May 18, 2006
    Inventor: Spyridon Vlassis
  • Publication number: 20060099917
    Abstract: In many circuits, including those operating in radio frequency (RF), there is commonly a need to perform DC offset cancellation. The DC offset is an error in an output signal in respect to the input that may cause a circuit to enter into undesirable or non-tolerable conditions of operation. While in most cases a static solution is provided the use of an analog loop may be inappropriate because of the adverse impact on speed. By adding a fast feedback loop finely impacting the adjustment of an amplifier, both the initial calibration is achieved as well as a recalibration of the system.
    Type: Application
    Filed: November 9, 2005
    Publication date: May 11, 2006
    Inventors: Konstantinos Papathanasiou, Spyridon Vlassis