Patents by Inventor Tom W. Kwan

Tom W. Kwan 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: 7336131
    Abstract: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be improved.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: February 26, 2008
    Assignee: Broadcom Corporation
    Inventors: Arya R. Behzad, Klaas Bult, Ramon A. Gomez, Chi-Hung Lin, Tom W. Kwan, Oscar E. Agazzi, John L. Creigh, Mehdi Hatamian, David E. Kruse, Arthur Abnous, Henry Samueli
  • Patent number: 7305045
    Abstract: Low voltage swing pad driver and receiver. A transmitter portion and a receiver portion are implemented within various devices that communicate using low voltage swing pads communicatively coupled via a trace. The transmitter portion of one device generates a current signal that is pushed/pulled to a low voltage swing pad and is then passed across the trace to another low voltage swing pad. The transmitter portion includes a current driver that outputs the current signal to the low voltage swing pads, and the receiver portion includes a trans-impedance amplifier that transforms the received current signal into a voltage signal. The low voltage swing pad driver and receiver generates a relatively low voltage swing when compared to CMOS full-scale voltage swings thereby significantly reducing the possibility of introducing any noise and/or distortion of data that is communicated via the interface.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: December 4, 2007
    Assignee: Broadcom Corporation
    Inventors: Sumant Ranganathan, Tom W. Kwan
  • Patent number: 7259956
    Abstract: The present invention provides several scalable integrated circuit high density capacitors and their layout techniques. The capacitors are scaled, for example, by varying the number of metal layers and/or the area of the metal layers used to from the capacitors. The capacitors use different metallization patterns to form the metal layers, and different via patterns to couple adjacent metal layers. In embodiments, optional shields are included as the top-most and/or bottom-most layers of the capacitors, and/or as side shields, to reduce unwanted parasitic capacitance.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: August 21, 2007
    Assignee: Broadcom Corporation
    Inventors: Victor Chiu-Kit Fong, Eric Bruce Blecker, Tom W. Kwan, Ning Li, Sumant Ranganathan, Chao Tang, Pieter Vorenkamp
  • Patent number: 7253763
    Abstract: An analog-to-digital converter (ADC) disposed in a data reception path to convert data from an analog format to a digital format is switched between two or more power modes to conserve power when data is not being received. ADC stays in a lower power-lower precision mode until an inbound data is detected, at which time the ADC switches to a higher power-higher precision mode to convert the data. Once data conversion is completed, the ADC switches back to the lower power-lower precision mode to conserve power.
    Type: Grant
    Filed: September 5, 2006
    Date of Patent: August 7, 2007
    Assignee: Broadcom Corporation
    Inventors: Srinivasa H. Garlapati, Paul Anthony Lettieri, Jason A. Trachewsky, Greg H. Efland, Tom W. Kwan
  • Patent number: 7148750
    Abstract: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be improved.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: December 12, 2006
    Assignee: Broadcom Corporation
    Inventors: Arya R. Behzad, Klaas Bult, Ramon A. Gomez, Chi-Hung Lin, Tom W. Kwan, Oscar E. Agazzi, John L. Creigh, Mehdi Hatamian, David E. Kruse, Arthur Abnous, Henry Samueli
  • Patent number: 7116259
    Abstract: An analog-to-digital converter (ADC) disposed in a data reception path to convert data from an analog format to a digital format is switched between two or more power modes to conserve power when data is not being received. ADC stays in a lower power-lower precision mode until an inbound data is detected, at which time the ADC switches to a higher power-higher precision mode to convert the data. Once data conversion is completed, the ADC switches back to the lower power-lower precision mode to conserve power.
    Type: Grant
    Filed: May 18, 2004
    Date of Patent: October 3, 2006
    Assignee: Broadcom Corporation
    Inventors: Srinivasa H. Garlapati, Paul Anthony Lettieri, Jason A. Trachewsky, Gregory H. Efland, Tom W. Kwan
  • Patent number: 7092043
    Abstract: An integrated receiver with channel selection and image rejection substantially implemented on a single CMOS integrated circuit is described. A receiver front end provides programable attenuation and a programable gain low noise amplifier. Frequency conversion circuitry advantageously uses LC filters integrated onto the substrate in conjunction with image reject mixers to provide sufficient image frequency rejection. Filter tuning and inductor Q compensation over temperature are performed on chip. The filters utilize multi track spiral inductors. The filters are tuned using local oscillators to tune a substitute filter, and frequency scaling during filter component values to those of the filter being tuned. In conjunction with filtering, frequency planning provides additional image rejection. The advantageous choice of local oscillator signal generation methods on chip is by PLL out of band local oscillation and by direct synthesis for in band local oscillator.
    Type: Grant
    Filed: November 12, 1999
    Date of Patent: August 15, 2006
    Assignee: Broadcom Corporation
    Inventors: Pieter Vorenkamp, Klaas Bult, Frank Carr, Christopher M. Ward, Ralph Duncan, Tom W. Kwan, James Y. C. Chang, Haideh Khorramabadi
  • Patent number: 7053715
    Abstract: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be improved.
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: May 30, 2006
    Assignee: Broadcom Corporation
    Inventors: Arya R. Behzad, Klaas Bult, Ramon A. Gomez, Chi-Hung Lin, Tom W. Kwan, Oscar E. Agazzi, John L. Creigh, Mehdi Hatamian, David E. Kruse, Arthur Abnous, Henry Samueli
  • Patent number: 7038533
    Abstract: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be improved.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: May 2, 2006
    Assignee: Broadcom Corporation
    Inventors: Arya R. Behzad, Klaas Bult, Ramon A. Gomez, Chi-Hung Lin, Tom W. Kwan, Oscar E. Agazzi, John L. Creigh, Mehdi Hatamian, David E. Kruse, Arthur Abnous, Henry Samueli
  • Patent number: 7038545
    Abstract: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be improved.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: May 2, 2006
    Assignee: Broadcom Corporation
    Inventors: Arya R. Behzad, Klaas Bult, Ramon A. Gomez, Chi-Hung Lin, Tom W. Kwan, Oscar E. Agazzi, John L. Creigh, Mehdi Hatamian, David E. Kruse, Arthur Abnous, Henry Samueli
  • Patent number: 7019598
    Abstract: An integrated VCO having an improved tuning range over process and temperature variations. There is therefore provided in a present embodiment of the invention an integrated VCO. The VCO comprises, a substrate, a VCO tuning control circuit responsive to a VCO state variable that is disposed upon the substrate, and a VCO disposed upon the substrate, having a tuning control voltage input falling within a VCO tuning range for adjusting a VCO frequency output, and having its tuning range adjusted by the tuning control circuit in response to the VCO state variable.
    Type: Grant
    Filed: September 22, 2003
    Date of Patent: March 28, 2006
    Assignee: Broadcom Corporation
    Inventors: Ralph Duncan, Tom W. Kwan
  • Patent number: 6937177
    Abstract: A data shuffler apparatus shuffles input bits to perform dynamic element matching. The shuffler apparatus includes N input shufflers, each input shuffler having N input terminals and N output terminals, each input terminal of each input shuffler receiving a respective one of the input bits. The apparatus also includes N output shufflers, each output shuffler having N input terminals and N output terminals, the input and output shufflers being interconnected such that each of the N output terminals of each input shuffler is connected to a respective input terminal of a different one of the N output shufflers.
    Type: Grant
    Filed: May 18, 2004
    Date of Patent: August 30, 2005
    Assignee: Broadcom Corporation
    Inventor: Tom W. Kwan
  • Patent number: 6930545
    Abstract: Provided is a switched capacitor feedback circuit including two or more input ports configured to receive a corresponding a number of input signals and at least one output port. The output port is configured to output an adjusting signal. The input signals includes a number of primary signals and two or more reference signals that are associated with a first timing phase of operation. The adjusting signal is produced based upon a comparison between the primary signals the reference signals. Also provided is a pair of active devices having gates coupled together and structured to receive the adjusting signal. The active devices are configured to provide a gain to the adjusting signal in accordance with a predetermined gain factor, and facilitate an adjustment to the number of primary signals based upon the gain during a second timing phase of operation.
    Type: Grant
    Filed: August 16, 2004
    Date of Patent: August 16, 2005
    Assignee: Broadcom Corporation
    Inventors: Tom W. Kwan, Ralph Duncan, Frank W. Singor
  • Publication number: 20040252041
    Abstract: A data shuffler apparatus shuffles input bits to perform dynamic element matching. The shuffler apparatus includes N input shufflers, each input shuffler having N input terminals and N output terminals, each input terminal of each input shuffler receiving a respective one of the input bits. The apparatus also includes N output shufflers, each output shuffler having N input terminals and N output terminals, the input and output shufflers being interconnected such that each of the N output terminals of each input shuffler is connected to a respective input terminal of a different one of the N output shufflers.
    Type: Application
    Filed: May 18, 2004
    Publication date: December 16, 2004
    Inventor: Tom W. Kwan
  • Patent number: 6828860
    Abstract: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be improved.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: December 7, 2004
    Assignee: Broadcom Corporation
    Inventors: Arya R. Behzad, Klaas Bult, Ramon A. Gomez, Chi-Hung Lin, Tom W. Kwan, Oscar E. Agazzi, John L. Creigh, Mehdi Hatamian, David E. Kruse, Arthur Abnous, Henry Samueli
  • Patent number: 6803829
    Abstract: An integrated VCO having an improved tuning range over process and temperature variations. There is therefore provided in a present embodiment of the invention an integrated VCO. The VCO comprises, a substrate, a VCO tuning control circuit responsive to a VCO state variable that is disposed upon the substrate, and a VCO disposed upon the substrate, having a tuning control voltage input falling within a VCO tuning range for adjusting a VCO frequency output, and having its tuning range adjusted by the tuning control circuit in response to the VCO state variable.
    Type: Grant
    Filed: June 17, 2002
    Date of Patent: October 12, 2004
    Assignee: Broadcom Corporation
    Inventors: Ralph Duncan, Tom W. Kwan
  • Patent number: 6801577
    Abstract: A transmitter portion and a receiver portion are implemented within various devices that communicate using low voltage swing pads communicatively coupled via a trace. The transmitter portion of one device generates a current signal that is pushed/pulled to a low voltage swing pad and is then passed across the trace to another low voltage swing pad. The transmitter portion includes a current driver that outputs the current signal to the low voltage swing pads, and the receiver portion includes a trans-impedance amplifier that transforms the received current signal into a voltage signal. The low voltage swing pad driver and receiver generates a relatively low voltage swing when compared to CMOS full-scale voltage swings thereby significantly reducing the possibility of introducing any noise and/or distortion of data that is communicated via the interface.
    Type: Grant
    Filed: July 16, 2002
    Date of Patent: October 5, 2004
    Assignee: Broadcom Corporation
    Inventors: Sumant Ranganathan, Tom W. Kwan
  • Patent number: 6798283
    Abstract: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be improved.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: September 28, 2004
    Assignee: Broadcom Corporation
    Inventors: Arya R. Behzad, Klaas Bult, Ramon A. Gomez, Chi-Hung Lin, Tom W. Kwan, Oscar E. Agazzi, John L. Creigh, Mehdi Hatamian, David E. Kruse, Arthur Abnous, Henry Samueli
  • Patent number: 6781451
    Abstract: Provided is a switched capacitor feedback circuit including two or more input ports configured to receive a corresponding a number of input signals and at least one output port. The output port is configured to output an adjusting signal. The input signals includes a number of primary signals and two or more reference signals that are associated with a first timing phase of operation. The adjusting signal is produced based upon a comparison between the primary signals the reference signals. Also provided is a pair of active devices having gates coupled together and structured to receive the adjusting signal. The active devices are configured to provide a gain to the adjusting signal in accordance with a predetermined gain factor, and facilitate an adjustment to the number of primary signals based upon the gain during a second timing phase of operation.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: August 24, 2004
    Assignee: Broadcom Corporation
    Inventors: Tom W. Kwan, Ralph Duncan, Frank W. Singor
  • Patent number: 6762702
    Abstract: A data shuffler apparatus shuffles input bits to perform dynamic element matching. The shuffler apparatus includes N input shufflers, each input shuffler having N input terminals and N output terminals, each input terminal of each input shuffler receiving a respective one of the input bits. The apparatus also includes N output shufflers, each output shuffler having N input terminals and N output terminals, the input and output shufflers being interconnected such that each of the N output terminals of each input shuffler is connected to a respective input terminal of a different one of the N output shufflers.
    Type: Grant
    Filed: August 22, 2002
    Date of Patent: July 13, 2004
    Assignee: Broadcom Corporation
    Inventor: Tom W. Kwan