Patents by Inventor Chengzhou Wang

Chengzhou Wang 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).

  • CMOS class AB power amplifier with cancellation of nonlinearity due to change in gate capacitance of a NMOS input transistor with switching
    Patent number: 6828858
    Abstract: To an existing class AB amplifier receiving at a gate of one of a NMOS or a PMOS type CMOS transistor an input signal, the gate of this CMOS transistor having a nonlinear gate capacitance with its switched operation, is added another, opposite-type, one of a NMOS or a PMOS type CMOS transistor that also receives at its gate the same input signal. The nonlinear gate capacitance of this other CMOS transistor is essentially opposite to the nonlinear gate capacitance of the existing CMOS transistor that receives the input signal within the class AB amplifier. This other transistor serves to compensate for the nonlinear gate capacitance of the existing CMOS transistor. Any nonlinearity due, in particular, to any nonlinear change in gate capacitance of a CMOS transistor that is used in particular within a class AB amplifier is thus substantially canceled.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: December 7, 2004
    Assignee: The Regents of the University of California
    Inventors: Larry Larson, Chengzhou Wang
  • CMOS class AB power amplifier with cancellation of nonlinearity due to change in gate capacitance of a NMOS input transistor with switching
    Publication number: 20030193371
    Abstract: To an existing class AB amplifier receiving at a gate of one of a NMOS or a PMOS type CMOS transistor an input signal, the gate of this CMOS transistor having a nonlinear gate capacitance with its switched operation, is added another, opposite-type, one of a NMOS or a PMOS type CMOS transistor that also receives at its gate the same input signal. The nonlinear gate capacitance of this other CMOS transistor is essentially opposite to the nonlinear gate capacitance of the existing CMOS transistor that receives the input signal within the class AB amplifier. This other transistor serves to compensate for the nonlinear gate capacitance of the existing CMOS transistor. Any nonlinearity due, in particular, to any nonlinear change in gate capacitance of a CMOS transistor that is used in particular within a class AB amplifier is thus substantially canceled.
    Type: Application
    Filed: April 12, 2002
    Publication date: October 16, 2003
    Inventors: Larry Larson, Chengzhou Wang