Patents by Inventor Runhua Sun

Runhua Sun 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).

  • Publication number: 20070072571
    Abstract: Techniques for cancelling DC offset are described. A DC offset cancellation circuit in a receiver cancels DC offsets caused by leaked LO (local oscillator) signals from a LO signal generator. The receiver first calibrates itself by using the DC offset cancellation circuit during a transmit mode. During the calibration, the DC offset cancellation circuit stores the DC offset voltage signal caused by the leaked LO signals. During a receiving mode when the receiver is receiving a signal, the receiver subtracts the stored DC offset voltage signal from the received signal to cancel the DC offsets caused by leaked LO signals.
    Type: Application
    Filed: January 28, 2006
    Publication date: March 29, 2007
    Inventors: Runhua Sun, Christian Holenstein, James Jaffee
  • Patent number: 6825730
    Abstract: A charge-pump and a method are provided for conditioning the phase detector output in a phase-locked loop (PLL). The method comprises: accepting a pair of differential phase detector (PD) output signals (up/upb and dn/dnb); connecting each pair of differential PD outputs to first and second charge-pump differential sections; supplying differential charge-pump outputs (Vout+/Vout−) in response to the pair of differential PD output signals; and, disconnecting the charge-pump differential section outputs from the loop filter inputs when the PD differential outputs (up/dn and upb/dnb) are equal. In some aspects, supplying differential charge-pump outputs (Vout+/Vout−) in response to the pair of differential PD output signals includes sourcing a first current through the first charge-pump differential section and sourcing a second current through the second charge-pump differential section. Then, the method further comprises maintaining the first current equal to the second current.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: November 30, 2004
    Assignee: Applied Micro Circuits Corporation
    Inventor: Runhua Sun
  • Patent number: 6664853
    Abstract: An impedance element connecting the outputs of two transistors of a wide-bandwidth amplifier forms a zero. The output of transistor is connected to a current source. The wide-bandwidth amplifier has a bandwidth greater than conventional amplifiers utilizing a single current source without an increase in power dissipation.
    Type: Grant
    Filed: January 31, 2002
    Date of Patent: December 16, 2003
    Assignee: Applied Micro Circuits Corporation
    Inventors: Runhua Sun, Thomas Clark Bryan, Zhixiang Jason Liu
  • Patent number: 6538512
    Abstract: A two-stage op-amp circuit including a double-cascode telescopic op-amp circuit in the input stage and a fully-differential op-amp circuit in the output stage and having very high open-loop DC gain, very high unity-gain frequency, and relatively very low power consumption is presented. The input stage op-amp circuit and the output stage op-amp circuit are each comprised of a plurality of electrically connected MOSFET's. The input stage op-amp circuit provides very high gain, high input resistance, and large common mode rejection. The output stage op-amp circuit provides gain, low output resistance, and minimal output loss.
    Type: Grant
    Filed: July 18, 2002
    Date of Patent: March 25, 2003
    Assignee: Globespanvirata, Inc.
    Inventor: Runhua Sun
  • Publication number: 20020175757
    Abstract: A two-stage op-amp circuit including a double-cascode telescopic op-amp circuit in the input stage and a fully-differential op-amp circuit in the output stage and having very high open-loop DC gain, very high unity-gain frequency, and relatively very low power consumption is presented. The input stage op-amp circuit and the output stage op-amp circuit are each comprised of a plurality of electrically connected MOSFET's. The input stage op-amp circuit provides very high gain, high input resistance, and large common mode rejection. The output stage op-amp circuit provides gain, low output resistance, and minimal output loss.
    Type: Application
    Filed: July 18, 2002
    Publication date: November 28, 2002
    Inventor: Runhua Sun
  • Patent number: 6476675
    Abstract: A two-stage op-amp circuit including a double-cascode telescopic op-amp circuit in the input stage and a fully-differential op-amp circuit in the output stage and having very high open-loop DC gain, very high unity-gain frequency, and relatively very low power consumption is presented. The input stage op-amp circuit and the output stage op-amp circuit are each comprised of a plurality of electrically connected MOSFET's. The input stage op-amp circuit provides very high gain, high input resistance, and large common mode rejection. The output stage op-amp circuit provides gain, low output resistance, and minimal output loss.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: November 5, 2002
    Assignee: GlobespanVirata, Inc.
    Inventor: Runhua Sun
  • Patent number: 6353361
    Abstract: A differential, two-stage op-amp circuit comprised of a plurality of electrically connected MOSFET's and including a telescopic op-amp circuit integrated with gain-boost amplifier circuits in the input stage and a fully-differential op-amp circuit in the output stage and having very high open-loop DC gain, very high unity-gain frequency, and considerably low power consumption is presented. The gain-boost amplifiers are configured as fully-differential op-amps, one being configured to be electrically connected to PMOS FET circuitry and the other being configured to be electrically connected to NMOS FET circuitry. The input stage op-amp circuit provides high gain, high input resistance, and large common mode rejection. The gain-boost op-amp circuits and the input stage form a local unity-gain feedback, and the outputs of the gain-boost op-amp circuits are adaptively stabilized. The output stage op-amp circuit provides gain, low output resistance, and minimal output loss.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: March 5, 2002
    Assignee: Globespan, Inc.
    Inventor: Runhua Sun