Patents by Inventor Chi-Mun Ho

Chi-Mun Ho 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: 9077514
    Abstract: An integrated circuit having a clock synchronizing circuit is described. The clock synchronizing circuit includes an input-output buffer and a plurality of sampling buffer circuits. The input-output buffer receives an input signal and generating an output signal. Each sampling buffer circuit receives the output signal and a sampling clock signal. Each sampling buffer circuit generates a first sampled output by sampling the output signal at the rising edge of the corresponding sampling clock signal and a second sampled output by sampling the output signal on the falling edge of the corresponding sampling clock signal. The sampling clock signal has a predetermined phase difference at each of the plurality of sampling buffer circuits.
    Type: Grant
    Filed: January 28, 2014
    Date of Patent: July 7, 2015
    Assignee: Altera Corporation
    Inventors: Chi Mun Ho, Kin Hong Au
  • Patent number: 7889249
    Abstract: A system and method for canceling dark photocurrent in a color sensor circuit is disclosed. A color sensor is described including a color sensor circuit, a dark color sensor circuit, and a differential amplifier circuit. The color sensor circuit receives photocurrent from a color component of a light input. The color sensor circuit outputs a first voltage indicating intensity of the color component. The dark color sensor circuit receives dark photocurrent and outputs a second voltage indicating an offset voltage. The differential amplifier circuit is coupled to the color sensor circuit and to the dark color sensor circuit. The differential amplifier circuit receives the first and second voltages and outputs a final output that cancels contributions of the offset voltage in the first voltage due to the dark photocurrent.
    Type: Grant
    Filed: July 8, 2010
    Date of Patent: February 15, 2011
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Boon Keat Tan, Chi Mun Ho, Kevin Len Lim
  • Publication number: 20100277624
    Abstract: A system and method for canceling dark photocurrent in a color sensor circuit is disclosed. A color sensor is described including a color sensor circuit, a dark color sensor circuit, and a differential amplifier circuit. The color sensor circuit receives photocurrent from a color component of a light input. The color sensor circuit outputs a first voltage indicating intensity of the color component. The dark color sensor circuit receives dark photocurrent and outputs a second voltage indicating an offset voltage. The differential amplifier circuit is coupled to the color sensor circuit and to the dark color sensor circuit. The differential amplifier circuit receives the first and second voltages and outputs a final output that cancels contributions of the offset voltage in the first voltage due to the dark photocurrent.
    Type: Application
    Filed: July 8, 2010
    Publication date: November 4, 2010
    Applicant: Avago Technologies ECBU (Singapore) Pte. Ltd
    Inventors: Boon Keat Tan, Chi Mun Ho, Kevin Len Li Lim
  • Patent number: 7773134
    Abstract: A system and method for canceling dark photocurrent in a color sensor circuit is disclosed. A color sensor is described including a color sensor circuit, a dark color sensor circuit, and a differential amplifier circuit. The color sensor circuit receives photocurrent from a color component of a light input. The color sensor circuit outputs a first voltage indicating intensity of the color component. The dark color sensor circuit receives dark photocurrent and outputs a second voltage indicating an offset voltage. The differential amplifier circuit is coupled to the color sensor circuit and to the dark color sensor circuit. The differential amplifier circuit receives the first and second voltages and outputs a final output that cancels contributions of the offset voltage in the first voltage due to the dark photocurrent.
    Type: Grant
    Filed: March 15, 2004
    Date of Patent: August 10, 2010
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Boon Keat Tan, Chi Mun Ho, Kevin Len Li Lim
  • Patent number: 7638756
    Abstract: An optical encoder includes a coding element having a track with multiple transparent sections, a light source positioned to output light to the track, and a photodetector array, positioned to detect light that passes through the transparent sections of the track. The photodetectors of the photodetector array have larger width dimensions than the width dimensions of the transparent sections of the track. Resolution of the optical encoder may be adjusted by changing the resolution of the coding element.
    Type: Grant
    Filed: June 17, 2008
    Date of Patent: December 29, 2009
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Chee Keong Chong, Kay Keat Khoo, Chi Mun Ho
  • Patent number: 7491927
    Abstract: The color sensing circuit includes a light detector to receive light and to generate a signal that is dependent on the received light. The light detector includes a first electrode coupled to a first node and a second electrode coupled to a second predetermined signal. A storage device is provided that includes a first node and a second node coupled to the second predetermined signal. A first switch is provided that selectively couples the first node with the first electrode of the storage device based on a charge control signal. A signal processing circuit is provided that includes a first electrode and an output to generate an output signal that represents the light received by the light detector. A second switch is also provided that selectively couples the first electrode of the storage device with the first electrode of the signal processing circuit based on an evaluate control signal. The signal processing circuit selectively asserts the charge control signal and evaluate control signal.
    Type: Grant
    Filed: June 24, 2004
    Date of Patent: February 17, 2009
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Boon Keat Tan, Chi Mun Ho, Len Li Kevin Lim
  • Patent number: 7449675
    Abstract: An optical encoder includes a coding element having a track with multiple transparent sections, a light source positioned to output light to the track, and a photodetector array, positioned to detect light that passes through the transparent sections of the track. The photodetectors of the photodetector array have larger width dimensions than the width dimensions of the transparent sections of the track. Resolution of the optical encoder may be adjusted by changing the resolution of the coding element.
    Type: Grant
    Filed: August 2, 2004
    Date of Patent: November 11, 2008
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Chee Keong Chong, Kay Keat Khoo, Chi Mun Ho
  • Publication number: 20080245956
    Abstract: An optical encoder includes a coding element having a track with multiple transparent sections, a light source positioned to output light to the track, and a photodetector array, positioned to detect light that passes through the transparent sections of the track. The photodetectors of the photodetector array have larger width dimensions than the width dimensions of the transparent sections of the track. Resolution of the optical encoder may be adjusted by changing the resolution of the coding element.
    Type: Application
    Filed: June 17, 2008
    Publication date: October 9, 2008
    Inventors: Chee Keong Chong, Kay Keat Khoo, Chi Mun Ho
  • Patent number: 7349017
    Abstract: A color sensor is implemented on a single integrated circuit chip. The color sensor includes a plurality of color sensor circuits and a gain selection control. Each color sensor circuit in the plurality of color sensor circuits includes a light detector, an amplifier and a gain selection circuit. The amplifier is connected to the light detector. The amplifier amplifies a signal from the light detector. The gain selection circuit is connected to the amplifier. The gain selection controls gain of the amplifier. The gain selection circuit includes a variable feedback resistance. The gain selection control selects a separate value of the variable feedback resistance for each color sensor circuit.
    Type: Grant
    Filed: April 21, 2004
    Date of Patent: March 25, 2008
    Assignee: Avago Technologies ECBU IP Pte Ltd
    Inventors: Boon Keat Tan, Chi Mun Ho
  • Patent number: 7310090
    Abstract: A switch panel having a touch plate, image generator, and imaging system. The touch plate includes an optically transparent layer having first and second sides. The optically transparent layer having an index of refraction greater than that of air. A light source generates a light signal that is reflected between the first and second sides of the touch plate within the transparent layer. The imaging system records an image of the first surface. An image generator displays an image that includes a plurality of button positions to a person viewing the touch plate from the first side. A portion of the light signal is reflected toward the second surface at an angle greater than the critical angle in the optically transparent layer when the first surface is touched. The imaging system determines the location of the touch from the location of the reflected light.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: December 18, 2007
    Assignee: Avago Technologies ECBM IP (Singapore) Pte Ltd.
    Inventors: Chi Mun Ho, Chin Hin Oon, Kean Loo Kah
  • Patent number: 6980473
    Abstract: A memory device and a method for compensating for a load current in the memory device. The memory device includes a plurality of I/O buffers where each I/O buffer includes an I/O write-buffer driver circuit. The I/O write-buffer driver circuit is coupled to a load current compensation circuit. Although each I/O buffer includes an I/O write-buffer circuit, a single load current compensation circuit may be coupled to several I/O write-buffer driver circuits. The load current compensation circuit generates a load compensation current for each I/O buffer circuit that is not being programmed. The load compensation current increases the load current so that a drain-side programming voltage (VPROG) drives a substantially constant load current, wherein the drain-side programming voltage is substantially independent of the number of bits being programmed.
    Type: Grant
    Filed: October 1, 2003
    Date of Patent: December 27, 2005
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Edward V. Bautista, Jr., Ken Cheong Cheah, Chi-Mun Ho
  • Publication number: 20050212774
    Abstract: A switch panel having a touch plate, image generator, and imaging system. The touch plate includes an optically transparent layer having first and second sides. The optically transparent layer having an index of refraction greater than that of air. A light source generates a light signal that is reflected between the first and second sides of the touch plate within the transparent layer. The imaging system records an image of the first surface. An image generator displays an image that includes a plurality of button positions to a person viewing the touch plate from the first side. A portion of the light signal is reflected toward the second surface at an angle greater than the critical angle in the optically transparent layer when the first surface is touched. The imaging system determines the location of the touch from the location of the reflected light.
    Type: Application
    Filed: March 25, 2004
    Publication date: September 29, 2005
    Inventors: Chi Mun Ho, Chin Hin Oon, Kean Loo Kah
  • Publication number: 20050200732
    Abstract: A system and method for canceling dark photocurrent in a color sensor circuit is disclosed. A color sensor is described including a color sensor circuit, a dark color sensor circuit, and a differential amplifier circuit. The color sensor circuit receives photocurrent from a color component of a light input. The color sensor circuit outputs a first voltage indicating intensity of the color component. The dark color sensor circuit receives dark photocurrent and outputs a second voltage indicating an offset voltage. The differential amplifier circuit is coupled to the color sensor circuit and to the dark color sensor circuit. The differential amplifier circuit receives the first and second voltages and outputs a final output that cancels contributions of the offset voltage in the first voltage due to the dark photo current.
    Type: Application
    Filed: March 15, 2004
    Publication date: September 15, 2005
    Inventors: Boon Keat Tan, Chi Mun Ho, Kevin Len Li Lim