Patents by Inventor Jinwen Xiao

Jinwen Xiao 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: 20080136391
    Abstract: A DC-DC digital pulse width modulated power supply is disclosed for generating a DC regulated output voltage. A digital control node has a digital control voltage disposed thereon for controlling the operation of the supply, wherein the digital control voltage has a substantially zero voltage when the output voltage of the supply is at a desired regulation, the digital control voltage having a resolution defined by a least significant bit (LSB). An input node receives a DC analog reference voltage defining the output voltage of the supply. A difference device determines the difference between the analog reference voltage and the output voltage to generate said digital control voltage. An LSB variation device varies the size of the LSB without varying the value of the digital control voltage for a substantially zero difference between the analog reference voltage and the output voltage.
    Type: Application
    Filed: January 29, 2008
    Publication date: June 12, 2008
    Applicant: SILICON LABORATORIES INC.
    Inventors: JINWEN XIAO, KA Y. LEUNG, DOUGLAS R. HOLBERG
  • Patent number: 7323855
    Abstract: A DC-DC digital pulse width modulated power supply is disclosed for generating a DC regulated output voltage. A digital control node has a digital control voltage disposed thereon for controlling the operation of the supply, wherein the digital control voltage has a substantially zero voltage when the output voltage of the supply is at a desired regulation, the digital control voltage having a resolution defined by a least significant bit (LSB). An input node receives a DC analog reference voltage defining the output voltage of the supply. A difference device determines the difference between the analog reference voltage and the output voltage to generate said digital control voltage. An LSB variation device varies the size of the LSB without varying the value of the digital control voltage for a substantially zero difference between the analog reference voltage and the output voltage.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: January 29, 2008
    Assignee: Silicon Laboratories Inc.
    Inventors: Jinwen Xiao, Ka Y. Leung, Douglas R. Holberg
  • Patent number: 7301488
    Abstract: An apparatus and method for minimizing limit cycle oscillations within a switched power supply includes providing a programmable dither signal as an input to the digital control loop connected between an output and a control input of the switched power supply. The dither signal minimizes limit cycle oscillations from the output of the switched power supply.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: November 27, 2007
    Assignee: Silicon Laboratories Inc.
    Inventors: Ka Y. Leung, Jinwen Xiao
  • Patent number: 7245512
    Abstract: A digital PID controller for controlling the operation of a switching power converter is disclosed. A data converter is provided for converting the analog sense voltage to a digital sense voltage. A difference circuit then determines the difference between the digital sense voltage and a reference voltage as a digital error voltage, which reference voltage represents a desired output DC voltage for the power converter. A digital compensator processes the digital error voltage. The digital compensator includes a PID compensation network for compensating the digital error signal with a discrete time PID control law and a postprocessing filter for processing the output of the PID compensation network, comprised of a sinc filter with variable parameters to define the operating characteristics thereof, such that a first notch associated therewith can be placed at a desired frequency.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: July 17, 2007
    Assignee: Silicon Laboratories Inc.
    Inventors: Ka Y. Leung, Kafai Leung, Jinwen Xiao
  • Patent number: 7212061
    Abstract: An apparatus for providing over current protection for a digital pulse width modulator is disclosed. The apparatus includes first logic circuitry for generating a primary interrupt indicating that a detected output current is greater than a threshold current. Second logic circuitry blanks out current spikes in the output current occurring on a leading pulse edge of at least one of a plurality of outputs of the digital pulse-width modulator.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: May 1, 2007
    Assignee: Silicon Laboratories Inc.
    Inventors: Kafai Leung, Ka Y. Leung, Jinwen Xiao
  • Publication number: 20060227860
    Abstract: An apparatus and method for minimizing limit cycle oscillations within a switched power supply includes providing a programmable dither signal as an input to the digital control loop connected between an output and a control input of the switched power supply. The dither signal minimizes limit cycle oscillations from the output of the switched power supply.
    Type: Application
    Filed: March 31, 2005
    Publication date: October 12, 2006
    Inventors: Ka Leung, Jinwen Xiao
  • Publication number: 20060220630
    Abstract: A DC-DC digital pulse width modulated power supply is disclosed for generating a DC regulated output voltage. A digital control node has a digital control voltage disposed thereon for controlling the operation of the supply, wherein the digital control voltage has a substantially zero voltage when the output voltage of the supply is at a desired regulation, the digital control voltage having a resolution defined by a least significant bit (LSB). An input node receives a DC analog reference voltage defining the output voltage of the supply. A difference device determines the difference between the analog reference voltage and the output voltage to generate said digital control voltage. An LSB variation device varies the size of the LSB without varying the value of the digital control voltage for a substantially zero difference between the analog reference voltage and the output voltage.
    Type: Application
    Filed: March 31, 2005
    Publication date: October 5, 2006
    Inventors: Jinwen Xiao, Ka Leung, Douglas Holberg
  • Patent number: 7061421
    Abstract: A differential analog-to-digital data converter (ADC) is disclosed for receiving a positive input signal and a negative input signal. A distributed resistive device is provided having taps associated therewith. A plurality of comparators each having a signal input and a reference input are provided, the signal input connected to one of the positive and negative input signals and the reference input connected to a tap on said distributed resistive device. A driver drives current through the distributed resistive device with one of the taps of the distributed resistive device disposed at substantially the other of the positive and negative input signals. A current varying device varys the current through the distributed resistive device to vary the voltage between taps.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: June 13, 2006
    Assignee: Silicon Laboratories Inc.
    Inventors: Jinwen Xiao, Ka Y. Leung, Douglas R. Holberg
  • Publication number: 20060023479
    Abstract: A digital PID controller for controlling the operation of a switching power converter is disclosed. A data converter is provided for converting the analog sense voltage to a digital sense voltage. A difference circuit then determines the difference between the digital sense voltage and a reference voltage as a digital error voltage, which reference voltage represents a desired output DC voltage for the power converter. A digital compensator processes the digital error voltage. The digital compensator includes a PID compensation network for compensating the digital error signal with a discrete time PID control law and a postprocessing filter for processing the output of the PID compensation network, comprised of a sinc filter with variable parameters to define the operating characteristics thereof, such that a first notch associated therewith can be placed at a desired frequency.
    Type: Application
    Filed: March 31, 2005
    Publication date: February 2, 2006
    Inventors: Ka Leung, Kafai Leung, Jinwen Xiao
  • Publication number: 20060022732
    Abstract: An apparatus for providing over current protection for a digital pulse width modulator is disclosed. The apparatus includes first logic circuitry for generating a primary interrupt indicating that a detected output current is greater than a threshold current. Second logic circuitry blanks out current spikes in the output current occurring on a leading pulse edge of at least one of a plurality of outputs of the digital pulse-width modulator.
    Type: Application
    Filed: March 31, 2005
    Publication date: February 2, 2006
    Inventors: Kafai Leung, Ka Leung, Jinwen Xiao
  • Publication number: 20060025892
    Abstract: A method for controlling the output of a switching power converter to account for high and low current loads is disclosed. A reference voltage is generated with a voltage reference generator representing a desired DC output voltage for the power converter. Then the DC voltage output of the power converter is sensed with a digital control system and generating switching control signals to control the operation thereof to minimize the difference between sensed DC voltage and the reference voltage. The current through the power converter is then determined and the operation of the voltage reference generator controlled to set the value of the reference voltage to a level that is a function of the sensed current so as to anticipate future current loading.
    Type: Application
    Filed: March 31, 2005
    Publication date: February 2, 2006
    Inventors: Ka Leung, Jinwen Xiao