Patents by Inventor Chao-Cheng Lee

Chao-Cheng Lee 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: 9520842
    Abstract: A transmission line driver circuit includes: a transmission line driving amplifier having a first transmission terminal and a second transmission terminal; a first signal node; a second signal node; a first adjustable resistor positioned between the first transmission terminal and the first signal node; a second adjustable resistor positioned between the second transmission terminal and the second signal node; an internal node; a first divider resistor positioned between the first signal node and the internal node; a second divider resistor positioned between the second signal node and the internal node; a comparing circuit for comparing a divided voltage at the internal node with a reference voltage to generate a comparison signal; and an adjusting circuit for adjusting resistance of at least one of the first and second adjustable resistors according to the comparison signal.
    Type: Grant
    Filed: September 1, 2015
    Date of Patent: December 13, 2016
    Assignee: REALTEK SEMICONDUCOR CORP.
    Inventors: Chao-Cheng Lee, Jian-Ru Lin, Chien-Ming Wu, Shih-Wei Wang
  • Patent number: 9391583
    Abstract: A transmission line driver circuit includes: a transmission line driving amplifier having a first transmission terminal and a second transmission terminal; a first signal node; a second signal node; a first adjustable resistor positioned between the first transmission terminal and the first signal node; a second adjustable resistor positioned between the second transmission terminal and the second signal node; a first voltage difference generating circuit coupled with two terminals of the first adjustable resistor to generate a first voltage difference value; a second voltage difference generating circuit coupled with two terminals of the second adjustable resistor to generate a second voltage difference value; sample-and-hold circuits for generating sampled signals according to the first voltage difference value and the second voltage difference value; a comparing circuit for comparing the sampled signals; and an adjusting circuit for adjusting resistance of the first and/or second adjustable resistors accor
    Type: Grant
    Filed: September 1, 2015
    Date of Patent: July 12, 2016
    Assignee: REALTEK SEMICONDUCTOR CORP.
    Inventors: Chao-Cheng Lee, Jian-Ru Lin, Shih-Wei Wang, Guan-Hong Ke
  • Publication number: 20160099689
    Abstract: A transmission line driver circuit includes: a transmission line driving amplifier having a first transmission terminal and a second transmission terminal; a first signal node; a second signal node; a first adjustable resistor positioned between the first transmission terminal and the first signal node; a second adjustable resistor positioned between the second transmission terminal and the second signal node; an internal node; a first divider resistor positioned between the first signal node and the internal node; a second divider resistor positioned between the second signal node and the internal node; a comparing circuit for comparing a divided voltage at the internal node with a reference voltage to generate a comparison signal; and an adjusting circuit for adjusting resistance of at least one of the first and second adjustable resistors according to the comparison signal.
    Type: Application
    Filed: September 1, 2015
    Publication date: April 7, 2016
    Applicant: Realtek Semiconductor Corp.
    Inventors: Chao-Cheng LEE, Jian-Ru LIN, Chien-Ming WU, Shih-Wei WANG
  • Publication number: 20160094196
    Abstract: A transmission line driver circuit includes: a transmission line driving amplifier having a first transmission terminal and a second transmission terminal; a first signal node; a second signal node; a first adjustable resistor positioned between the first transmission terminal and the first signal node; a second adjustable resistor positioned between the second transmission terminal and the second signal node; a first voltage difference generating circuit coupled with two terminals of the first adjustable resistor to generate a first voltage difference value; a second voltage difference generating circuit coupled with two terminals of the second adjustable resistor to generate a second voltage difference value; sample-and-hold circuits for generating sampled signals according to the first voltage difference value and the second voltage difference value; a comparing circuit for comparing the sampled signals; and an adjusting circuit for adjusting resistance of the first and/or second adjustable resistors accor
    Type: Application
    Filed: September 1, 2015
    Publication date: March 31, 2016
    Applicant: Realtek Semiconductor Corp.
    Inventors: Chao-Cheng LEE, Jian-Ru LIN, Shih-Wei WANG, Guan-Hong KE
  • Patent number: 9269674
    Abstract: The present invention discloses an integrated circuit having electromagnetic shielding capability and the manufacturing method thereof. An embodiment of the said integrated circuit comprises: a semiconductor circuit structure including a first surface which covers an electromagnetic radiation area; an electromagnetic shielding layer covering the first surface and including at least one contact; and at least one conducting path operable to electrically connect the at least one contact with a steady voltage and thereby shield off the electromagnetic wave from the electromagnetic radiation area, wherein the current running through the electromagnetic shielding layer is zero or less than the maximum current running through the electromagnetic radiation area.
    Type: Grant
    Filed: June 2, 2015
    Date of Patent: February 23, 2016
    Assignee: REALTEK SEMICONDUCTOR CORPORATION
    Inventors: Chao-Cheng Lee, Wen-Shan Wang
  • Publication number: 20150364429
    Abstract: The present invention discloses an integrated circuit having electromagnetic shielding capability and the manufacturing method thereof. An embodiment of the said integrated circuit comprises: a semiconductor circuit structure including a first surface which covers an electromagnetic radiation area; an electromagnetic shielding layer covering the first surface and including at least one contact; and at least one conducting path operable to electrically connect the at least one contact with a steady voltage and thereby shield off the electromagnetic wave from the electromagnetic radiation area, wherein the current running through the electromagnetic shielding layer is zero or less than the maximum current running through the electromagnetic radiation area.
    Type: Application
    Filed: June 2, 2015
    Publication date: December 17, 2015
    Inventors: CHAO-CHENG LEE, WEN-SHAN WANG
  • Patent number: 9030265
    Abstract: This invention discloses a crystal oscillator, in which by appropriately designing the gain of an amplifier to achieve high trans-conductance and low power consumption. This crystal oscillator includes a first pad, coupled to a first node of a crystal, for receiving a crystal oscillating signal outputted from the crystal; an amplifier, coupled to the first pad, for amplifying the crystal oscillating signal to generate an amplifying signal; an inverter, coupled to the amplifier, for inverting the amplifying signal; and a second pad, coupled to a second node of the crystal, for outputting an oscillating signal to the crystal.
    Type: Grant
    Filed: August 13, 2010
    Date of Patent: May 12, 2015
    Assignee: Realtek Semiconductor Corp.
    Inventor: Chao-Cheng Lee
  • Patent number: 8975971
    Abstract: A digitally controlled LC-tank oscillator is constructed by connecting different tuning circuits to a LC tank. The tuning circuit includes a single bank of tuning cells, a dual bank of tuning cells, or a fractional tuning circuit. Each of said tuning cells in the tuning circuit includes a tuning circuit element and a memory cell.
    Type: Grant
    Filed: July 7, 2010
    Date of Patent: March 10, 2015
    Assignee: Realtek Semiconductor Corporation
    Inventors: Hong-Yean Hsieh, Chao-Cheng Lee
  • Patent number: 8891682
    Abstract: A mixer for the elimination of harmonic mixing in signal transmission is presented. The mixer incorporates a mixing unit and a modulation output unit. The mixing unit receives an input signal and a modulated signal, and outputs an output signal after signal mixing. The modulation output unit is for the generation of modulated signals, which are usually pulse-width modulated. The modulation output unit includes a delta sigma modulator and a digital domain code generator. The delta sigma modulator outputs the modulated signal responding to the received oscillation signal and digital domain code, the digital domain code generator generates the digital domain code in order to provide digital domain sine wave code for the use of the delta sigma modulator. The oscillation signal may be a signal of constant hi-frequency, or a signal that has a frequency larger or equal to that of the input signal by an integer factor.
    Type: Grant
    Filed: November 13, 2006
    Date of Patent: November 18, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chao-Cheng Lee, Ying-Yao Lin
  • Patent number: 8817862
    Abstract: An equalizer and a related equalizing method for equalizing signal reflection caused by a stub at a transmitting end are provided. The equalizer includes a summing device and a delay device. The summing device is utilized for adding a feedback delay signal to the input signal to generate the equalized signal. The delay device is coupled to the summing device, and utilized for delaying the equalized signal to generate the feedback delay signal. Wherein the delay device has a variable delay time and the variable delay time is a non-integer multiple of a bit time of the input signal.
    Type: Grant
    Filed: March 16, 2011
    Date of Patent: August 26, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chao-Cheng Lee, Tzu-Chien Tzeng
  • Patent number: 8723708
    Abstract: A successive approximation analog to digital converter and a conversion method thereof are provided. The successive approximation analog to digital converter includes a sample circuit, a conversion circuit, and a filtering control circuit. The sample circuit is configured to sample an analog voltage from an analog signal. The conversion circuit is configured to convert the analog voltage into a digital voltage. The filtering control circuit is configured to transmit a filtering control signal to the sample circuit according to the digital voltage. The sample circuit further samples a next analog voltage from the analog signal and adjusts the next analog voltage into an adjusted analog voltage according to the filtering control signal. The conversion circuit further converts the adjusted analog voltage into a next digital voltage, wherein the next digital voltage is a filtered digital voltage.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: May 13, 2014
    Assignee: Realtek Semiconductor Corporation
    Inventor: Chao-Cheng Lee
  • Publication number: 20140062550
    Abstract: A phase locked loop comprises a loop filter and a charge pump circuit. The loop filter comprises a parallel capacitor, a serial resistor and a serial capacitor. A first terminal of the serial resistor is electrically connected to a first terminal of the parallel capacitor. A first terminal of the serial capacitor is electrically connected to the second terminal of the serial resistor, and a second terminal of the serial capacitor is electrically connected to a second terminal of the parallel capacitor. The charge pump circuit comprises a first charge pump and a second charge pump. The first charge pump is electrically connected to the first terminal of the serial resistor, and the second charge pump is electrically connected to the second terminal of the serial resistor. The phase lock loop can reduce output jitter and therefore increases the performance of the phase lock loop.
    Type: Application
    Filed: September 3, 2013
    Publication date: March 6, 2014
    Applicant: REALTEK SEMICONDUCTOR CORP.
    Inventors: Chao-Cheng Lee, Hai-Bing Zhao
  • Patent number: 8521105
    Abstract: A transmitter for transmitting a transmission signal is disclosed. The transmitter includes: a gain stage, for receiving an input signal and amplifying the input signal according to a gain to generate an amplified signal; and an output stage, coupled to the gain stage, for receiving a first reference voltage signal and the amplified signal and utilizing the first reference voltage signal to perform a predetermined operation on the amplified signal to generate the output signal.
    Type: Grant
    Filed: March 23, 2007
    Date of Patent: August 27, 2013
    Assignee: Realtek Semiconductor Corp.
    Inventor: Chao-Cheng Lee
  • Patent number: 8482359
    Abstract: This invention provides an equalization apparatus for equalizing an input signal on a cable. The equalization apparatus comprises a cable equalizer for equalizing a cable attenuation effect of the input signal to output a first equalization signal; and a stub equalizer for equalizing a stub effect of the first equalization signal to output an outputting equalization signal.
    Type: Grant
    Filed: September 2, 2010
    Date of Patent: July 9, 2013
    Assignee: Realtek Semiconductor Corp.
    Inventor: Chao-Cheng Lee
  • Patent number: 8416025
    Abstract: A reference assisted control system and method thereof are disclosed. The method comprises: receiving a first input signal and a second control signal; generating a first intermediate signal in accordance with a difference between the first input signal and the first output signal; filtering the second control signal to generate a second intermediate signal; performing a weighted sum of the first intermediate signal and the second intermediate signal to generate the control signal; and outputting the first output signal in accordance with the control signal.
    Type: Grant
    Filed: April 14, 2010
    Date of Patent: April 9, 2013
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chia-Liang Lin, Chao-Cheng Lee
  • Patent number: 8306175
    Abstract: A clock and data recovery circuit includes a voltage controlled oscillator for generating an output clock according to a control voltage signal, a loop filter for outputting the control voltage signal according to a current output, a charge pump unit for outputting the current output according to an error signal, and a controller for determining a run length corresponding to input data based on the output clock from the voltage controlled oscillator. The controller further controls at least one of the voltage controlled oscillator, the loop filter and the charge pump unit according to the run length to dynamically adjust loop bandwidth. A method of adjusting loop bandwidth is also disclosed.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: November 6, 2012
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chao-Cheng Lee, Tzu-Chien Tzeng
  • Publication number: 20120235763
    Abstract: An equalizer and a related equalizing method for equalizing signal reflection caused by a stub at a transmitting end are provided. The equalizer includes a summing device and a delay device. The summing device is utilized for adding a feedback delay signal to the input signal to generate the equalized signal. The delay device is coupled to the summing device, and utilized for delaying the equalized signal to generate the feedback delay signal. Wherein the delay device has a variable delay time and the variable delay time is a non-integer multiple of a bit time of the input signal.
    Type: Application
    Filed: March 16, 2011
    Publication date: September 20, 2012
    Inventors: Chao-Cheng Lee, Tzu-Chien Tzeng
  • Patent number: 8095101
    Abstract: A receiving device includes a mixer, an AC coupling circuit, a post-stage circuit, and a DC offset calibration circuit. The mixer is utilized for mixing an input signal with a local oscillating (LO) signal from an oscillator to generate a converted signal. The AC coupling circuit is coupled to the mixer and utilized for reducing at least one portion of DC offset of the converted signal to generate a filtered signal. The post-stage circuit is coupled to the AC coupling circuit and utilized for processing the filtered signal to generate an output signal. The DC offset calibration circuit is coupled to the post-stage circuit and utilized for providing at least a compensation current for the post-stage circuit to reduce DC offset of the output signal.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: January 10, 2012
    Assignee: Realtek Semiconductor Corp.
    Inventors: Pei-Ju Chiu, Chia-Jun Chang, Chao-Cheng Lee
  • Patent number: 8055233
    Abstract: A high linearity mixer circuit includes a commutation network comprising four switches to provide an electrical coupling between a first pair of circuit nodes and a second pair of circuit nodes, whereas the coupling has two states and is controlled by a pair of complementary logical signals. The mixer circuit further comprises a first pair of current-sourcing devices coupled to the first pair of circuit nodes and a second pair of current-sourcing devices coupled to the second pair of circuit nodes. The mixer circuit further includes a pair of capacitors to provide AC coupling, either between the first pair of circuit nodes and a first external circuit, or between the second pair of circuit nodes and a second external circuit.
    Type: Grant
    Filed: April 24, 2008
    Date of Patent: November 8, 2011
    Assignee: Realtek Semiconductor Corp.
    Inventors: Hong Yean Hsieh, Chao-Cheng Lee, Chia-Liang Lin
  • Publication number: 20110254631
    Abstract: A reference assisted control system and method thereof are disclosed. The method comprises: receiving a first input signal and a second control signal; generating a first intermediate signal in accordance with a difference between the first input signal and the first output signal; filtering the second control signal to generate a second intermediate signal; performing a weighted sum of the first intermediate signal and the second intermediate signal to generate the control signal; and outputting the first output signal in accordance with the control signal.
    Type: Application
    Filed: April 14, 2010
    Publication date: October 20, 2011
    Applicant: REALTEK SEMICONDUCTOR CORP.
    Inventors: Chia-Liang LIN, Chao-Cheng LEE