Patents by Inventor Kah Weng Lee

Kah Weng 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: 10660180
    Abstract: Various embodiments of a light source driver are disclosed. In one embodiment, the light source driver may have a driving transistor coupled directly to at least one light source without having additional switches such that the light source driver may be operated with a low voltage supply. Optionally, the light source drivers may have a bypassing circuit configured to reduce power consumption, and peaking current generator configured to speed up the turn on time of the at least one light source. At least some of the circuits, and block diagrams disclosed herein may be implemented using conventional CMOS design and manufacturing techniques and processes to provide, for example, at least one or more integrated circuits.
    Type: Grant
    Filed: October 23, 2014
    Date of Patent: May 19, 2020
    Assignee: Avago Technologies International Sales Pte. Limited
    Inventor: Kah Weng Lee
  • Patent number: 9960671
    Abstract: A capacitive isolation system, capacitive isolator, and method of operating the same are disclosed. The capacitive isolation system is described to include a first semiconductor die and a second semiconductor die each having capacitive elements established thereon and positioned in a face-to-face configuration. An isolation layer is provided between the first and second semiconductor die so as to establish an isolation boundary therebetween. Capacitive coupling is used to carry information across the isolation boundary.
    Type: Grant
    Filed: December 31, 2014
    Date of Patent: May 1, 2018
    Assignee: AVAGO TECHNOLOGIES GENERAL IP (SINGAPORE) PTE. LTD.
    Inventors: Dominique Ho, Kwee Chong Chang, Kah Weng Lee, Brian J. Misek
  • Publication number: 20160190918
    Abstract: A capacitive isolation system, capacitive isolator, and method of operating the same are disclosed. The capacitive isolation system is described to include a first semiconductor die and a second semiconductor die each having capacitive elements established thereon and positioned in a face-to-face configuration. An isolation layer is provided between the first and second semiconductor die so as to establish an isolation boundary therebetween. Capacitive coupling is used to carry information across the isolation boundary.
    Type: Application
    Filed: December 31, 2014
    Publication date: June 30, 2016
    Inventors: Dominique Ho, Kwee Chong Chang, Kah Weng Lee, Brian J. Misek
  • Publication number: 20160119993
    Abstract: Various embodiments of a light source driver are disclosed. In one embodiment, the light source driver may have a driving transistor coupled directly to at least one light source without having additional switches such that the light source driver may be operated with a low voltage supply. Optionally, the light source drivers may have a bypassing circuit configured to reduce power consumption, and peaking current generator configured to speed up the turn on time of the at least one light source. At least some of the circuits, and block diagrams disclosed herein may be implemented using conventional CMOS design and manufacturing techniques and processes to provide, for example, at least one or more integrated circuits.
    Type: Application
    Filed: October 23, 2014
    Publication date: April 28, 2016
    Inventor: Kah Weng Lee
  • Patent number: 8188814
    Abstract: According to one embodiment, there is provided a high voltage isolation dual capacitor communication system comprising communication drive and sense electrodes and corresponding first and second capacitors that are formed in two separate devices. The two devices are electrically connected in series to provide a single galvanically-isolated communication system that exhibits high breakdown voltage performance in combination with good signal coupling. The system effects communications between drive and receive circuits through the first and second capacitors, and in a preferred embodiment is capable of effecting relatively high-speed digital communications. The system may be formed in a small package using, by way of example, CMOS or other semiconductor fabrication and packaging processes.
    Type: Grant
    Filed: March 3, 2009
    Date of Patent: May 29, 2012
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Gek Yong Ng, Kah Weng Lee, Fun Kok Chow
  • Patent number: 8035317
    Abstract: According to one embodiment, there is provided an optocoupler system configured to generate current signals having high, low and no amplitude portions in response to the receipt of logic high and low input signals. The varying amplitude portions of the current signals are used to drive other portions of the isolation circuitry, and result in reduced power consumption and dissipation, as well as reduced pulse width distortion.
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: October 11, 2011
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Kah Weng Lee, Fun Kok Chow
  • Publication number: 20100213874
    Abstract: According to one embodiment, there is provided an optocoupler system configured to generate current signals having high, low and no amplitude portions in response to the receipt of logic high and low input signals. The varying amplitude portions of the current signals are used to drive other portions of the isolation circuitry, and result in reduced power consumption and dissipation, as well as reduced pulse width distortion.
    Type: Application
    Filed: February 26, 2009
    Publication date: August 26, 2010
    Applicant: Avage Technologies ECBU (Singapore) Pte.Ltd.
    Inventors: Kah Weng Lee, Fun Kok Chow
  • Patent number: 7741935
    Abstract: According to one embodiment, there is provided a semiconductor digital communication device comprising communication drive and sense electrodes formed in a single plane, where the electrodes have relatively high sidewalls. The relatively high sidewalls permit low electrical field densities to be obtained in the sense and drive electrodes during operation, and further permit very high breakdown voltages to be obtained between the electrodes, and between the drive electrode and an underlying ground plane substrate. The device effects communications between drive and receive circuits through the drive and sense electrodes by capacitive means, and in a preferred embodiment is capable of effecting relatively high-speed digital communications. The device may be formed in a small package using, by way of example, CMOS or other semiconductor fabrication and packaging processes.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: June 22, 2010
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Fun Kok Chow, Gek Yong Ng, Kah Weng Lee
  • Publication number: 20090206960
    Abstract: According to one embodiment, there is provided a high voltage isolation dual capacitor communication system comprising communication drive and sense electrodes and corresponding first and second capacitors that are formed in two separate devices. The two devices are electrically connected in series to provide a single galvanicly-isolated communication system that exhibits high breakdown voltage performance in combination with good signal coupling. The system effects communications between drive and receive circuits through the first and second capacitors, and in a preferred embodiment is capable of effecting relatively high-speed digital communications. The system may be formed in a small package using, by way of example, CMOS or other semiconductor fabrication and packaging processes.
    Type: Application
    Filed: March 3, 2009
    Publication date: August 20, 2009
    Applicant: Avago Technologies ECBU (Singapore) Pte Ltd.
    Inventors: Gek Yong Ng, Fun Kok Chow, Kah Weng Lee
  • Patent number: 7554073
    Abstract: A light sensor having first and second photodetectors and a current mirror is disclosed. The first photodetector receives a light signal and generates a light current proportional to the light intensity received by the first photodetector and a dark current that is independent of the light intensity. The second photodetector is connected in series with the first photodetector at a first node. The second photodetector has a covering that prevents light from reaching the second photodetector. The second photodetector generates a current equal to the dark current. The first photodetector is connected to a power source and the second photodetector is connected to an output node. The current mirror is connected to the first node and the output node and generates an output current that is proportional to the light current through the output node when the output node is connected to an external circuit.
    Type: Grant
    Filed: January 22, 2007
    Date of Patent: June 30, 2009
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Kok Keong Richard Lum, Kah Weng Lee, Bin Zhang
  • Patent number: 7548699
    Abstract: A power supply generates a supply voltage that varies from a first voltage level to a second voltage level. A first current source is coupled to the power supply and generates a current that varies due to channel-length modulation. A channel-length modulation (CLM) compensation mechanism is provided to reduce the current variation of the first current source by compensating the channel-length modulation (CLM) of the first current source.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: June 16, 2009
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Kah Weng Lee, Bin Zhang
  • Patent number: 7547902
    Abstract: An optocoupler system includes a buffer, isolation, and a detector. The system includes a current transfer ratio (CTR) with a temperature coefficient. The buffer includes a light source that generates light that passes through the isolation. A detector receives light that passes through the isolation and generates an output signal based on the received light. A current transfer ratio (CTR) temperature coefficient compensation mechanism is provided that generates a base signal with a temperature coefficient that compensates the temperature coefficient of the CTR.
    Type: Grant
    Filed: December 5, 2007
    Date of Patent: June 16, 2009
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Kah Weng Lee, Bin Zhang
  • Publication number: 20080173796
    Abstract: A light sensor having first and second photodetectors and a current mirror is disclosed. The first photodetector receives a light signal and generates a light current proportional to the light intensity received by the first photodetector and a dark current that is independent of the light intensity. The second photodetector is connected in series with the first photodetector at a first node. The second photodetector has a covering that prevents light from reaching the second photodetector. The second photodetector generates a current equal to the dark current. The first photodetector is connected to a power source and the second photodetector is connected to an output node. The current mirror is connected to the first node and the output node and generates an output current that is proportional to the light current through the output node when the output node is connected to an external circuit.
    Type: Application
    Filed: January 22, 2007
    Publication date: July 24, 2008
    Inventors: Kok Keong Richard Lum, Kah Weng Lee, Bin Zhang
  • Patent number: 7326947
    Abstract: An optocoupler system includes a buffer, isolation, and a detector. The system includes a current transfer ratio (CTR) with a temperature coefficient. The buffer includes a light source that generates light that passes through the isolation. A detector receives light that passes through the isolation and generates an output signal based on the received light. A current transfer ratio (CTR) temperature coefficient compensation mechanism is provided that generates a base signal with a temperature coefficient that compensates the temperature coefficient of the CTR.
    Type: Grant
    Filed: November 15, 2005
    Date of Patent: February 5, 2008
    Assignee: Avago Technologies ECBU IP Pte Ltd
    Inventors: Kah Weng Lee, Bin Zhang
  • Patent number: 7221227
    Abstract: In one embodiment, a method is provided for reducing output current oscillations of a driver provided with i) a current sensing circuit that senses excessive current draws of an output stage of the driver, and ii) a feedback control circuit that reduces the excessive current draws. In accordance with the method, an output of the current sensing circuit is coupled to an input of a common source amplifier with source degeneration. The output of the common source amplifier is coupled to a node between an input stage and an amplification stage of the driver. The common source amplifier is configured to be activated when the current sensing circuit senses an excessive current draw of the output stage, at which time the feedback control circuit is also activated. Related apparatus is also disclosed.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: May 22, 2007
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Kah Weng Lee, Bin Zhang