Patents by Inventor Chi-Hsi Su

Chi-Hsi Su 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: 20230036760
    Abstract: The present invention discloses a DAC method having signal calibration mechanism used in a DAC circuit having thermometer-controlled current sources generating an output analog signal according to a total current thereof and a control circuit. Current offset values of the current sources are retrieved. The current offset values are sorted to generate a turn-on order, in which the current offset values are separated into current offset groups according to the turn-on order, the signs of each neighboring two groups being opposite such that the current offset values cancel each other when the current sources turn on according to the turn-on order to keep an absolute value of a total offset not larger than a half of a largest absolute value of the current offset values. The current sources are turned on based on the turn-on order according to a thermal code included in an input digital signal.
    Type: Application
    Filed: July 11, 2022
    Publication date: February 2, 2023
    Inventors: KAI-YUE LIN, HSUAN-TING HO, LIANG-WEI HUANG, CHI-HSI SU
  • Patent number: 11290306
    Abstract: A signal processing device includes a decision feedback equalizer and a coefficient adjusting circuit. The decision feedback equalizer includes a first equalizer configured to perform filtering on a first signal according to a set of first coefficients to generate a first filtered signal. The set of first coefficients includes multiple first coefficients. The coefficient adjusting circuit is configured to adaptively adjust one or more of the first coefficients according to an error signal. A limit operation of the first coefficients is selectively performed. When the limit operation of the first coefficients is performed, at least one of the first coefficients is set to a first predetermined value to generate a set of limited first coefficients.
    Type: Grant
    Filed: September 15, 2020
    Date of Patent: March 29, 2022
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chi-Hsi Su, Liang-Wei Huang
  • Publication number: 20210351905
    Abstract: A signal processing circuit, which includes: a first clock source, configured to generate a first clock signal; a phase adjusting circuit, configured to receive the first clock signal, and to generate a second clock signal and a third clock signal, wherein the second clock signal and the third clock signal have different phases; an error compensating circuit, configured to compensate an input signal according to an error signal, to generate an compensated input signal; an error calculating circuit, configured to generate the error signal according to the first clock signal, the third clock signal and the compensated input signal; and a receiving end ADC (Analog to Digital Converter), configured to sample the compensated input signal according to the second clock signal.
    Type: Application
    Filed: April 12, 2021
    Publication date: November 11, 2021
    Inventors: Yun-Tse Chen, Liang-Wei Huang, Chi-Hsi Su, Po-Han Lin
  • Patent number: 11171767
    Abstract: A signal processing circuit, which includes: a first clock source, configured to generate a first clock signal; a phase adjusting circuit, configured to receive the first clock signal, and to generate a second clock signal and a third clock signal, wherein the second clock signal and the third clock signal have different phases; an error compensating circuit, configured to compensate an input signal according to an error signal, to generate an compensated input signal; an error calculating circuit, configured to generate the error signal according to the first clock signal, the third clock signal and the compensated input signal; and a receiving end ADC (Analog to Digital Converter), configured to sample the compensated input signal according to the second clock signal.
    Type: Grant
    Filed: April 12, 2021
    Date of Patent: November 9, 2021
    Assignee: Realtek Semiconductor Corp.
    Inventors: Yun-Tse Chen, Liang-Wei Huang, Chi-Hsi Su, Po-Han Lin
  • Publication number: 20210226825
    Abstract: A signal processing device includes a decision feedback equalizer and a coefficient adjusting circuit. The decision feedback equalizer includes a first equalizer configured to perform filtering on a first signal according to a set of first coefficients to generate a first filtered signal. The set of first coefficients includes multiple first coefficients. The coefficient adjusting circuit is configured to adaptively adjust one or more of the first coefficients according to an error signal. A limit operation of the first coefficients is selectively performed. When the limit operation of the first coefficients is performed, at least one of the first coefficients is set to a first predetermined value to generate a set of limited first coefficients.
    Type: Application
    Filed: September 15, 2020
    Publication date: July 22, 2021
    Inventors: Chi-Hsi Su, Liang-Wei Huang
  • Publication number: 20210226654
    Abstract: A Radio Frequency Interference (RFI) estimation device for generating an estimated RFI signal includes a combiner, a first multiplier and a second multiplier. The combiner is configured to combine a first digital signal and a second signal to generate the estimated RFI signal. The first multiplier is configured to generate the first digital signal according to an in-phase signal and a first cosine signal. The second multiplier is configured to generate the second digital signal according to a quadrature-phase signal and a first sine signal. The first cosine signal and the first sine signal are generated based on a frequency and the in-phase signal and the quadrature-phase signal are generated based on the frequency and one or more harmonics of the frequency.
    Type: Application
    Filed: September 16, 2020
    Publication date: July 22, 2021
    Inventors: Chi-Hsi Su, Liang-Wei Huang
  • Patent number: 11057064
    Abstract: A Radio Frequency Interference (RFI) estimation device for generating an estimated RFI signal includes a combiner, a first multiplier and a second multiplier. The combiner is configured to combine a first digital signal and a second signal to generate the estimated RFI signal. The first multiplier is configured to generate the first digital signal according to an in-phase signal and a first cosine signal. The second multiplier is configured to generate the second digital signal according to a quadrature-phase signal and a first sine signal. The first cosine signal and the first sine signal are generated based on a frequency and the in-phase signal and the quadrature-phase signal are generated based on the frequency and one or more harmonics of the frequency.
    Type: Grant
    Filed: September 16, 2020
    Date of Patent: July 6, 2021
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chi-Hsi Su, Liang-Wei Huang
  • Patent number: 8181082
    Abstract: A wireless receiver system with automatic gain control, which includes a receiving path, an analog to digital converter, an automatic gain control (AGC) device and a controller. The controller has an adjacent channel interference off mode, an adjacent channel interference acquisition mode and an adjacent channel interference tracking mode to accordingly set the AGC device for adjusting the gains of a plurality of modules of the receiving path. Namely, the strengths of different adjacent channel interferences are appropriately adjusted to thereby obtain the best received signal quality.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: May 15, 2012
    Assignee: Sunplus Technology Co., Ltd.
    Inventors: Chi-Hsi Su, Wei Sheng Chang
  • Publication number: 20100235707
    Abstract: A wireless receiver system with automatic gain control, which includes a receiving path, an analog to digital converter, an automatic gain control (AGC) device and a controller. The controller has an adjacent channel interference off mode, an adjacent channel interference acquisition mode and an adjacent channel interference tracking mode to accordingly set the AGC device for adjusting the gains of a plurality of modules of the receiving path. Namely, the strengths of different adjacent channel interferences are appropriately adjusted to thereby obtain the best received signal quality.
    Type: Application
    Filed: March 31, 2009
    Publication date: September 16, 2010
    Applicant: Sunplus Technology Co., Ltd.
    Inventors: Chi-Hsi Su, Wei Sheng Chang
  • Patent number: 7733953
    Abstract: An apparatus and method for adaptively correcting I/Q imbalance, which is used in a receiver for correcting a received I/Q imbalanced signal to thus eliminate the I/Q imbalance. First, an interference amount caused by interference from an imbalanced in-phase signal to an imbalanced quadrature-phase signal is computed and accordingly subtracted from the quadrature-phase signal, so that a corrected quadrature-phase signal without phase imbalance is obtained. Next, a power of output in-phase signal, a power of output quadrature-phase signal, and a target are compared to thus determine an in-phase scaling factor and a quadrature-phase scaling factor. Finally, the imbalanced in-phase signal is multiplied by the in-phase scaling factor to thus obtain the output in-phase signal, and the corrected quadrature-phase signal is multiplied by the quadrature-phase scaling factor to thus obtain the output quadrature-phase signal.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: June 8, 2010
    Assignee: Sunplus Technology Co., Ltd.
    Inventor: Chi-Hsi Su
  • Patent number: 7649934
    Abstract: An apparatus and method for adaptively correcting I/Q imbalance, which is used in a receiver for correcting a received I/Q imbalanced signal to thus eliminate the I/Q imbalance. First, an interference amount caused by interference from an imbalanced in-phase signal to an imbalanced quadrature-phase signal is computed and accordingly subtracted from the quadrature-phase signal, so that a corrected quadrature-phase signal without phase imbalance is obtained. Next, a power of output in-phase signal, a power of output quadrature-phase signal, and a target are compared to thus determine an in-phase scaling factor and a quadrature-phase scaling factor. Finally, the imbalanced in-phase signal is multiplied by the in-phase scaling factor to thus obtain the output in-phase signal, and the corrected quadrature-phase signal is multiplied by the quadrature-phase scaling factor to thus obtain the output quadrature-phase signal.
    Type: Grant
    Filed: February 27, 2006
    Date of Patent: January 19, 2010
    Assignee: Sunplus Technology Co., Ltd.
    Inventor: Chi-Hsi Su
  • Publication number: 20090316839
    Abstract: An apparatus and method for adaptively correcting I/Q imbalance, which is used in a receiver for correcting a received I/Q imbalanced signal to thus eliminate the I/Q imbalance. First, an interference amount caused by interference from an imbalanced in-phase signal to an imbalanced quadrature-phase signal is computed and accordingly subtracted from the quadrature-phase signal, so that a corrected quadrature-phase signal without phase imbalance is obtained. Next, a power of output in-phase signal, a power of output quadrature-phase signal, and a target are compared to thus determine an in-phase scaling factor and a quadrature-phase scaling factor. Finally, the imbalanced in-phase signal is multiplied by the in-phase scaling factor to thus obtain the output in-phase signal, and the corrected quadrature-phase signal is multiplied by the quadrature-phase scaling factor to thus obtain the output quadrature-phase signal.
    Type: Application
    Filed: August 21, 2009
    Publication date: December 24, 2009
    Applicant: Sunplus Technology Co., Ltd.
    Inventor: Chi-Hsi Su
  • Publication number: 20070081614
    Abstract: An apparatus and method for adaptively correcting I/Q imbalance, which is used in a receiver for correcting a received I/Q imbalanced signal to thus eliminate the I/Q imbalance. First, an interference amount caused by interference from an imbalanced in-phase signal to an imbalanced quadrature-phase signal is computed and accordingly subtracted from the quadrature-phase signal, so that a corrected quadrature-phase signal without phase imbalance is obtained. Next, a power of output in-phase signal, a power of output quadrature-phase signal, and a target are compared to thus determine an in-phase scaling factor and a quadrature-phase scaling factor. Finally, the imbalanced in-phase signal is multiplied by the in-phase scaling factor to thus obtain the output in-phase signal, and the corrected quadrature-phase signal is multiplied by the quadrature-phase scaling factor to thus obtain the output quadrature-phase signal.
    Type: Application
    Filed: February 27, 2006
    Publication date: April 12, 2007
    Applicant: Sunplus Technology Co., Ltd.
    Inventor: Chi-Hsi Su