Patents by Inventor Brian E. Merrigan

Brian E. Merrigan 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).

  • Low voltage variable gain amplifier having constant common mode DC output
    Patent number: 6566951
    Abstract: A variable gain amplifier includes a differential transconductor, a differential gain stage, a DC compensation circuit and first and second load resistors. The differential transconductor has first and second differential voltage signal inputs and first and second differential current outputs. The differential gain stage selectively steers current from the first and second differential current outputs to first and second variable current outputs, respectively, and to first and second compensation current outputs, respectively, based on a differential gain control input. The first and second load resistors are coupled to the first and second variable current outputs, respectively. The DC compensation circuit combines current in the first and second compensation current outputs to form a DC compensation current and couples the DC compensation current to the first and second load resistors.
    Type: Grant
    Filed: October 25, 2001
    Date of Patent: May 20, 2003
    Assignee: LSI Logic Corporation
    Inventors: Brian E. Merrigan, Asad Ali
  • Mixer with stepped gain and constant common mode DC output bias voltage
    Patent number: 6429721
    Abstract: An mixer includes a differential signal input, a differential local oscillator input, a gain control input and a differential signal output. The mixer has a stepped signal gain from the differential signal input to the differential signal output which is variable from a first gain to a second, different gain as a function of the gain control input and has a substantially constant DC common mode output bias voltage at the differential signal output.
    Type: Grant
    Filed: October 25, 2001
    Date of Patent: August 6, 2002
    Assignee: LSI Logic Corporation
    Inventors: Philip J. Armitage, Brian E. Merrigan