Patents by Inventor Kam Hung Chan

Kam Hung Chan 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: 20240039488
    Abstract: The present disclosure provides a receiving circuit for adaptive impedance matching and an operating method thereof. The receiving circuit includes: a first amplification module configured to amplify an input signal input from an input end of the first amplification module to generate a first amplified signal; a frequency mixing module, an input end of which is connected to an output end of the first amplification module, and configured to down-convert the first amplified signal to generate a down-converted signal; and a second amplification module, an input end of which is connected to an output end of the frequency mixing module, and configured to amplify the down-converted signal to generate an output signal, wherein the first amplification module includes an active negative feedback structure for providing adaptive impedance matching in a first bandwidth range.
    Type: Application
    Filed: April 10, 2023
    Publication date: February 1, 2024
    Inventors: Zhongliang Zhou, Yongxue Qian, Xin Huang, Hao Meng, Guangjie Cai, Chun fai Wong, Kam hung Chan, Tai yin Wong
  • Patent number: 9638584
    Abstract: A differential on-chip temperature sensor circuit can be implemented in a standard complementary metal-oxide-semiconductor (CMOS) process using PNP transistors. A pair of transistors have collector currents that are sensitive to voltage, both directly and due to saturation currents. A scaling resistor connects to the emitter of one transistor and its voltage compared to the other transistor's emitter voltage by an error amplifier that generates a bias voltage to current sources that are proportional to absolute temperature since the saturation current sensitivity is subtracted out. The current is mirrored to sink current through a multiplier resistor from an output. An amplifier connected across the multiplier resistor compares a reference voltage to set the DC bias independent of temperature sensitivity. The temperature sensitivity is proportional to the ratio of the multiplier resistor and the scaling resistor, and is multiplied by a mirroring factor. A differential output is provided.
    Type: Grant
    Filed: August 26, 2014
    Date of Patent: May 2, 2017
    Assignee: Hong Kong Applied Science and Technology Research Institute Company Limited
    Inventors: Chun Fai Wong, Leung Ling (Alan) Pun, Kam Hung Chan, Kwok Kuen (David) Kwong
  • Publication number: 20140362887
    Abstract: A differential on-chip temperature sensor circuit can be implemented in a standard complementary metal-oxide-semiconductor (CMOS) process using PNP transistors. A pair of transistors have collector currents that are sensitive to voltage, both directly and due to saturation currents. A scaling resistor connects to the emitter of one transistor and its voltage compared to the other transistor's emitter voltage by an error amplifier that generates a bias voltage to current sources that are proportional to absolute temperature since the saturation current sensitivity is subtracted out. The current is mirrored to sink current through a multiplier resistor from an output. An amplifier connected across the multiplier resistor compares a reference voltage to set the DC bias independent of temperature sensitivity. The temperature sensitivity is proportional to the ratio of the multiplier resistor and the scaling resistor, and is multiplied by a mirroring factor. A differential output is provided.
    Type: Application
    Filed: August 26, 2014
    Publication date: December 11, 2014
    Inventors: Chun Fai WONG, Leung Ling (Alan) PUN, Kam Hung CHAN, Kwok Kuen (David) KWONG
  • Patent number: 8864377
    Abstract: An on-chip temperature sensor circuit can be implemented in a standard complementary metal-oxide-semiconductor (CMOS) process using PNP transistors. A pair of transistors have collector currents that are sensitive to voltage, both directly and due to saturation currents. A scaling resistor connects to the emitter of one transistor and its voltage compared to the other transistor's emitter voltage by an error amplifier that generates a bias voltage to current sources that are proportional to absolute temperature since the saturation current sensitivity is subtracted out. The current is mirrored to sink current through a multiplier resistor from an output. An amplifier connected across the multiplier resistor compares a reference voltage to set the DC bias independent of temperature sensitivity. The temperature sensitivity is proportional to the ratio of the multiplier resistor and the scaling resistor, and is multiplied by a mirroring factor. A differential output may also be provided.
    Type: Grant
    Filed: March 9, 2012
    Date of Patent: October 21, 2014
    Assignee: Hong Kong Applied Science & Technology Research Institute Company Limited
    Inventors: Chun Fai Wong, Leung Ling (Alan) Pun, Kam Hung Chan, Kwok Kuen (David) Kwong
  • Publication number: 20130235903
    Abstract: An on-chip temperature sensor circuit can be implemented in a standard complementary metal-oxide-semiconductor (CMOS) process using PNP transistors. A pair of transistors have collector currents that are sensitive to voltage, both directly and due to saturation currents. A scaling resistor connects to the emitter of one transistor and its voltage compared to the other transistor's emitter voltage by an error amplifier that generates a bias voltage to current sources that are proportional to absolute temperature since the saturation current sensitivity is subtracted out. The current is mirrored to sink current through a multiplier resistor from an output. An amplifier connected across the multiplier resistor compares a reference voltage to set the DC bias independent of temperature sensitivity. The temperature sensitivity is proportional to the ratio of the multiplier resistor and the scaling resistor, and is multiplied by a mirroring factor. A differential output may also be provided.
    Type: Application
    Filed: March 9, 2012
    Publication date: September 12, 2013
    Applicant: Hong Kong Applied Science & Technology Research Institute Company Limited
    Inventors: Chun Fai WONG, Leung Ling (Alan) PUN, Kam Hung CHAN, Kwok Kuen (David) KWONG
  • Patent number: 8258852
    Abstract: A motor driver circuit for driving the gate node of a high-side driver transistor to a boosted voltage from a charge pump draws little or no static current from the charge pump. The gate node is pulled to the boosted voltage by a p-channel pullup-control transistor that is driven by p-channel transistors that are pumped by capacitors that cut off current flow to ground from the charge pump. An n-channel output-shorting transistor shorts the gate node to the output when the high-side driver is turned off. A coupling capacitor initializes the shorting transistor for each output transition. A p-channel output-sensing transistor generates a feedback to a second stage that drives the coupling capacitor. P-channel diode transistors and an n-channel equalizing transistor control the voltage on the coupling capacitor.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: September 4, 2012
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Lap Chi David Leung, Yat Tung Lai, Chun Fai Wong, Kam Hung Chan, Kwok Kuen David Kwong
  • Publication number: 20120126736
    Abstract: A motor driver circuit for driving the gate node of a high-side driver transistor to a boosted voltage from a charge pump draws little or no static current from the charge pump. The gate node is pulled to the boosted voltage by a p-channel pullup-control transistor that is driven by p-channel transistors that are pumped by capacitors that cut off current flow to ground from the charge pump. An n-channel output-shorting transistor shorts the gate node to the output when the high-side driver is turned off. A coupling capacitor initializes the shorting transistor for each output transition. A p-channel output-sensing transistor generates a feedback to a second stage that drives the coupling capacitor. P-channel diode transistors and an n-channel equalizing transistor control the voltage on the coupling capacitor.
    Type: Application
    Filed: November 18, 2010
    Publication date: May 24, 2012
    Applicant: Hong Kong Applied Science & Technology Research Institute Company Limited
    Inventors: Lap Chi (David) LEUNG, Yat Tung LAI, Chun Fai WONG, Kam Hung CHAN, Kwok Kuen KWONG
  • Patent number: 8179455
    Abstract: A Optical Black Pixel (OBP) cancellation circuit corrects offsets in sensors in a CCD/CMOS image sensor when reading dark pixels such at the periphery. A pixel voltage is switched to a sampling capacitor during two phases of the same pixel pulse. Sampling capacitors and feedback capacitors connect to differential inputs of an amplifier. An accumulating capacitor accumulates voltage differences and generates a common-mode voltage that is fed back to another sampling capacitor that stores an amplifier offset. The sampling capacitor and accumulating capacitor and their associated switches form a discrete-time first-order low-pass filter that filters the pixel voltage during the first phase. In the second phase the amplifier acts as a unity-gain amplifier to output an average of the pixel voltage differences generated during an OBP time when blackened or covered pixels are read from the image sensor.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: May 15, 2012
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Lap Chi (David) Leung, Yat Tung Lai, Chun Fai Wong, Kam Hung Chan, Kwok Kuen (David) Kwong
  • Publication number: 20110221938
    Abstract: A Optical Black Pixel (OBP) cancellation circuit corrects offsets in sensors in a CCD/CMOS image sensor when reading dark pixels such at the periphery. A pixel voltage is switched to a sampling capacitor during two phases of the same pixel pulse. Sampling capacitors and feedback capacitors connect to differential inputs of an amplifier. An accumulating capacitor accumulates voltage differences and generates a common-mode voltage that is fed back to another sampling capacitor that stores an amplifier offset. The sampling capacitor and accumulating capacitor and their associated switches form a discrete-time first-order low-pass filter that filters the pixel voltage during the first phase. In the second phase the amplifier acts as a unity-gain amplifier to output an average of the pixel voltage differences generated during an OBP time when blackened or covered pixels are read from the image sensor.
    Type: Application
    Filed: March 11, 2010
    Publication date: September 15, 2011
    Applicant: Hong Kong Applied Science & Technology Research Institute Company Limited
    Inventors: Lap Chi (David) LEUNG, Yat Tung LAI, Chun Fai WONG, Kam Hung CHAN, Kwok Kuen (David) KWONG
  • Publication number: 20110056242
    Abstract: A visible setting comprises a setting base and one or more gemstones or diamonds. The setting base comprises one or more upper fixing portions and a lower connection portion, each fixing portion is fixed to a girdle of a gemstone or diamond at certain fixing points to enable to fix the gemstone or diamond in its setting position. Except for the fixing points, the rest of the girdle, a crown and a table of the gemstone or diamond are exposed, and a pavilion of the gemstone or diamond is suspended, and thereby a culet of the gemstone or diamond and part of the pavilion around the culet are displaced away from the setting base to enable to be exposed, which enables external light to enter into the gemstone or diamond from the crown, the table and the exposed part of the pavilion. The present visible setting could enhance the reflection of light within the gemstones or diamonds, and make the gemstones or diamonds as brilliant as possible.
    Type: Application
    Filed: September 7, 2010
    Publication date: March 10, 2011
    Applicant: UNIVERSAL JEWELLERY DESIGN CENTER LIMITED
    Inventor: Kam Hung CHAN