Patents by Inventor Zhengxin Cao

Zhengxin Cao 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: 8411383
    Abstract: Various embodiments of the present invention provide systems and methods for signal offset cancellation. For example, a method for error cancellation is disclosed. The method includes: receiving an input signal that includes a second order error component; applying a transfer function to the processed input to reduce the second order error component; and providing an output signal that is the result of applying the transfer function to the input signal.
    Type: Grant
    Filed: December 31, 2009
    Date of Patent: April 2, 2013
    Assignee: LSI Corporation
    Inventors: Zhengxin Cao, Hao Qiong Chen, Shu Dong Cheng, De Qun Ma, Donghui Wang, Yan Xu
  • Publication number: 20120223781
    Abstract: Described embodiments provide a voltage controlled oscillator (VCO) that includes an operational amplifier (opamp). The opamp has a positive power supply input coupled to a power supply voltage, a negative power supply input coupled to a ground node, an inverting input coupled to a control voltage of the VCO, a noninverting input that receives a feedback signal, and an output providing a transistor control voltage. A transistor having a gate terminal coupled to the output of the opamp, a source terminal coupled to the power supply voltage, and a drain terminal coupled to a resistor coupled to ground, generates an output current. A current mirror generates a mirror current based on the output current. A current controlled oscillator (ICO) is coupled to the current mirror, and sets the frequency of the VCO output signal based upon the mirror current.
    Type: Application
    Filed: March 1, 2011
    Publication date: September 6, 2012
    Inventors: HaoQiong Chen, Zhengxin Cao, Qi Jian Ge
  • Publication number: 20110019301
    Abstract: Various embodiments of the present invention provide systems and methods for signal offset cancellation. For example, a method for error cancellation is disclosed. The method includes: receiving an input signal that includes a second order error component; applying a transfer function to the processed input to reduce the second order error component; and providing an output signal that is the result of applying the transfer function to the input signal.
    Type: Application
    Filed: December 31, 2009
    Publication date: January 27, 2011
    Inventors: Zhengxin Cao, Hao Qiong Chen, Shu Dong Cheng, De Qun Ma, Donghui Wang, Yan Xu