Patents by Inventor Tim Chan

Tim 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: 20170104481
    Abstract: An improved analog switch for use in an ultrasound elastography probe is disclosed. The improved analog switch results in less heat dissipation compared to prior art analog switches.
    Type: Application
    Filed: September 14, 2016
    Publication date: April 13, 2017
    Inventors: Isaac Ko, Ka Wai Ho, Wan Tim Chan
  • Publication number: 20160191036
    Abstract: Described herein are multiple designs for an improved analog switch for use in transmitting high voltage signals without using high voltage power supplies for the switch. The analog switches are able to pass and block input signals in the approximate range of ?100V to +100V. The use of translinear loops and a bootstrap configuration results in a constant on-resistance of the symmetrical switches and matches the conductance of each analog switch to the transconductance of an NMOS transistor, which can be easily stabilized with a constant gm biasing scheme. In certain embodiments, a shunt termination (T-switch) configuration is used for better off-isolation, and each of the symmetrical switches has its own translinear loop and thus flexibility of on-resistance and termination voltage.
    Type: Application
    Filed: October 21, 2015
    Publication date: June 30, 2016
    Inventors: Isaac Ko, Ka Wai Ho, Wan Tim Chan, Jimes Lei
  • Patent number: 8937565
    Abstract: An impedance matching transmission circuit for a transducer has a transmission medium connected to the transducer. A transmitting circuit is connected to the transmission medium with the transmitting circuit terminating in a reference circuit element. The transmitting circuit comprises an analog to digital converter having an analog input connected to the reference circuit element, and having a digital output. A digital to analog converter receives the digital output and generates an analog output signal in response thereto. A driver circuit is connected to the transmission medium and receives the analog output signal and supplies a driver signal to the transmission medium.
    Type: Grant
    Filed: August 22, 2012
    Date of Patent: January 20, 2015
    Assignee: Supertex, Inc.
    Inventors: Isaac Terasuth Ko, Ka Wai Ho, Wan Tim Chan
  • Publication number: 20120313485
    Abstract: An impedance matching transmission circuit for a transducer has a transmission medium connected to the transducer. A transmitting circuit is connected to the transmission medium with the transmitting circuit terminating in a reference circuit element. The transmitting circuit comprises an analog to digital converter having an analog input connected to the reference circuit element, and having a digital output. A digital to analog converter receives the digital output and generates an analog output signal in response thereto. A driver circuit is connected to the transmission medium and receives the analog output signal and supplies a driver signal to the transmission medium.
    Type: Application
    Filed: August 22, 2012
    Publication date: December 13, 2012
    Applicant: Supertex, Inc.
    Inventors: Isaac Terasuth KO, Ka Wai HO, Wan Tim CHAN
  • Patent number: 8269656
    Abstract: An impedance matching transmission circuit for a transducer has a transmission medium connected to the transducer. A transmitting circuit is connected to the transmission medium with the transmitting circuit terminating in a reference circuit element. The transmitting circuit comprises an analog to digital converter having an analog input connected to the reference circuit element, and having a digital output. A digital to analog converter receives the digital output and generates an analog output signal in response thereto. A driver circuit is connected to the transmission medium and receives the analog output signal and supplies a driver signal to the transmission medium.
    Type: Grant
    Filed: May 24, 2010
    Date of Patent: September 18, 2012
    Assignee: Supertex, Inc.
    Inventors: Isaac Terasuth Ko, Ka Wai Ho, Wan Tim Chan
  • Patent number: 8193839
    Abstract: A multi-level transmitter circuit with substantially constant output impedance has a capacitive transducer connected between a voltage input and ground. A first voltage path connects the voltage input to a first positive voltage source. The first voltage path is controlled by a first control signal. A second voltage path connects the voltage input to a second positive voltage source, less than the first positive voltage source. The second voltage path passes through a diode and is controlled by a second control signal. A third voltage path connects the voltage input to a third voltage source, less than ground, and is controlled by the second control signal. The impedance at the voltage input during the first control signal is substantially the same as the impedance at the voltage input during the second control signal.
    Type: Grant
    Filed: May 24, 2010
    Date of Patent: June 5, 2012
    Assignee: SuperTex, Inc.
    Inventors: Isaac Terasuth Ko, Ka Wai Ho, Wan Tim Chan
  • Patent number: 8160109
    Abstract: Aspects of the invention provide a method and system for synchronizing a transceiver and a framer in an optical transmission network. Subsequent to achieving synchronization of an inbound data stream, an internal framer may be adapted to inform a downstream device such as a full framer, that synchronization has already been attained. Accordingly, the downstream device may not need to perform resynchronization of the inbound data and can immediately start processing the inbound data. Advantageously, the internal framer may provide expedited error checking, handling and reporting prior to receipt of the data by the downstream device.
    Type: Grant
    Filed: December 27, 2002
    Date of Patent: April 17, 2012
    Assignee: Broadcom Corporation
    Inventors: Jay Proano, Sheila Oiu, Tim Chan, Hongtao Jiang
  • Publication number: 20110285457
    Abstract: A multi-level transmitter circuit with substantially constant output impedance has a capacitive transducer connected between a voltage input and ground. A first voltage path connects the voltage input to a first positive voltage source. The first voltage path is controlled by a first control signal. A second voltage path connects the voltage input to a second positive voltage source, less than the first positive voltage source. The second voltage path passes through a diode and is controlled by a second control signal. A third voltage path connects the voltage input to a third voltage source, less than ground, and is controlled by the second control signal. The impedance at the voltage input during the first control signal is substantially the same as the impedance at the voltage input during the second control signal.
    Type: Application
    Filed: May 24, 2010
    Publication date: November 24, 2011
    Inventors: Isaac Terasuth Ko, Ka Wai Ho, Wan Tim Chan
  • Publication number: 20110285561
    Abstract: An impedance matching transmission circuit for a transducer has a transmission medium connected to the transducer. A transmitting circuit is connected to the transmission medium with the transmitting circuit terminating in a reference circuit element. The transmitting circuit comprises an analog to digital converter having an analog input connected to the reference circuit element, and having a digital output. A digital to analog converter receives the digital output and generates an analog output signal in response thereto. A driver circuit is connected to the transmission medium and receives the analog output signal and supplies a driver signal to the transmission medium.
    Type: Application
    Filed: May 24, 2010
    Publication date: November 24, 2011
    Inventors: Isaac Terasuth Ko, Ka Wai Ho, Wan Tim Chan
  • Publication number: 20050086393
    Abstract: In general, in one aspect, the disclosure includes a description of a method that includes accessing network traffic metering data and controlling power consumption of individual ones of a set of network processor processing engines based on the metering data.
    Type: Application
    Filed: October 3, 2003
    Publication date: April 21, 2005
    Inventors: David Meng, Jian-Hui Huang, Tim Chan
  • Publication number: 20040086278
    Abstract: Aspects of the invention provide a method and system for synchronizing a transceiver and a framer in an optical transmission network. Subsequent to achieving synchronization of an inbound data stream, an internal framer may be adapted to inform a downstream device such as a full framer, that synchronization has already been attained. Accordingly, the downstream device may not need to perform resynchronization of the inbound data and can immediately start processing the inbound data. Advantageously, the internal framer may provide expedited error checking, handling and reporting prior to receipt of the data by the downstream device.
    Type: Application
    Filed: December 27, 2002
    Publication date: May 6, 2004
    Inventors: Jay Proano, Sheila Oiu, Tim Chan, Hongtao Jing