Patents by Inventor Wenhai Ni

Wenhai Ni 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).

  • Variable load circuit for reducing quadrature phase error
    Patent number: 7474715
    Abstract: A variable load circuit for adjusting a phase of a differential signal including a first transistor having a first terminal adapted to receive a first component of the differential signal, a second transistor having a first terminal adapted to receive a second component of the differential signal and a second terminal coupled to a second terminal of the first transistor, and a variable current source coupled to a third terminal of both the first and second transistors. The variable current source generates a bias current based on a control signal. For each of the first and second transistors, a first capacitance is created between the first and second terminals, and a second capacitance is created between the first and third terminals. The first and second capacitances are each a function of the bias current and thus the control signal and operate to adjust the phase of the differential signal.
    Type: Grant
    Filed: May 27, 2004
    Date of Patent: January 6, 2009
    Assignee: RF Micro Devices, Inc.
    Inventors: Wenhai Ni, Kelvin Kai Tuan Yan, Mark Alexander John Moffat