Patents by Inventor Tom Kwan

Tom 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).

  • Publication number: 20060192614
    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: Application
    Filed: February 2, 2006
    Publication date: August 31, 2006
    Inventors: Arya Behzad, Klaas Bult, Ramon Gomez, Chi-Hung Lin, Tom Kwan, Oscar Agazzi, John Creigh, Mehdi Hatamian, David Kruse, Arthur Abnous, Henry Samueli
  • Publication number: 20060023647
    Abstract: A second output transmission signal (“TX2”) added to a line driver is a scaled version of the main output transmission signal (“TX1”). TX2 is scaled from TX1 by a variable scale factor K. An adaptive hybrid circuit subtracts TX1 and TX2 from a line signal carrying both a line transmission signal and a line received signal (“RX”). A programmable impedance Ztune is coupled between the TX2 output of the line driver and the RX output of the adaptive hybrid circuit. A transmission echo in the output RX signal is measured. K and Ztune are then adaptively tuned to minimize the transmission echo. The hybrid in this case becomes a 4-port network, one port specifically added to adaptively cancel the transmission echo in the RX output of the adaptive hybrid circuit. Alternatively, the hybrid may be a 3-port hybrid including variable impedances to cancel the line transmission signal.
    Type: Application
    Filed: December 3, 2004
    Publication date: February 2, 2006
    Inventors: Tom Kwan, Sumant Ranganathan
  • Publication number: 20050285584
    Abstract: An integrated circuit and method in an integrated circuit for providing electrical power utilizing digital power regulation. Various aspects of the present invention provide an integrated circuit comprising a power supply module that outputs electrical power at an output voltage level. An error determination module may receive a power supply reference signal and a signal indicative of the output voltage level and output a power supply error signal. A digital controller module may receive the power supply error signal, digitally process the power supply error signal, and output a power supply control signal. A power output-monitoring module may monitor the electrical power output from the power supply module and output the signal indicative of the output voltage level. The power supply module may receive the power supply control signal and output the electrical power based, at least in part, on the power supply control signal.
    Type: Application
    Filed: April 20, 2005
    Publication date: December 29, 2005
    Inventor: Tom Kwan
  • Publication number: 20050260965
    Abstract: Provided are a method and system for removing an offset direct current (DC) component from an input waveform. The method includes multiplying the input waveform with a demodulation waveform to produce a first differential current signal. An absolute value representation of the demodulation waveform is multiplied with a reference DC offset value to produce a second differential current signal. The first and second differential current signals are then differenced.
    Type: Application
    Filed: April 27, 2005
    Publication date: November 24, 2005
    Applicant: Broadcom Corporation
    Inventors: Sumant Ranganathan, Tom Kwan, Hung-Sung Li
  • Publication number: 20050258893
    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: Application
    Filed: May 18, 2004
    Publication date: November 24, 2005
    Inventors: Srinivasa Garlapati, Paul Lettieri, Jason Trachewsky, Gregory Efland, Tom Kwan
  • Publication number: 20050243893
    Abstract: Provided are a method and system for demodulating a signal. The method includes receiving the signal along first and second signal paths within a demodulator having a common starting point. Impedance values along each of the paths are changed alternately in synchronism.
    Type: Application
    Filed: April 27, 2005
    Publication date: November 3, 2005
    Applicant: Broadcom Corporation
    Inventors: Sumant Ranganathan, Tom Kwan, Hung-Sung Li
  • Publication number: 20050238123
    Abstract: Provided are a method and system for digitizing a sensor model output signal. The system includes a filter, a demodulator coupled to the filter, a DC offset cancellation mechanism coupled to the demodulator, and an analog to digital converter (ADC). The ADC is directly coupled to the demodulator and the DC offset cancellation mechanism.
    Type: Application
    Filed: April 27, 2005
    Publication date: October 27, 2005
    Applicant: Broadcom Corporation
    Inventors: Sumant Ranganathan, Tom Kwan, Hung-Sung Li
  • Publication number: 20050189993
    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: Application
    Filed: December 6, 2004
    Publication date: September 1, 2005
    Inventors: Arya Behzad, Klaas Bult, Ramon Gomez, Chi-Hung Lin, Tom Kwan, Oscar Agazzi, John Creigh, Mehdi Hatamian, David Kruse, Arthur Abnous, Henry Samueli
  • Publication number: 20050135042
    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: Application
    Filed: December 17, 2004
    Publication date: June 23, 2005
    Inventors: Victor Chiu-Kit Fong, Eric Blecker, Tom Kwan, Ning Li, Sumant Ranganthan, Chao Tang, Pieter Vorenkamp
  • Publication number: 20050089158
    Abstract: A hybrid circuit that decouples gains for a transmit signal and a receive signal of a broadband modem that is coupled to a telephone line is provided. The hybrid circuit includes a multi-port transformer, a pair of line matching resistors, and a bridge circuit. The multi-port transformer includes a line coil electrically coupled to a telephone line, a linedriver coil magnetically coupled to the line coil and a receive coil that is also magnetically coupled to the line coil. In an alternate embodiment, a hybrid circuit is provided that includes a multi-port transformer in which the line coil, linedriver coil and receive coil include two coil segments. A broadband modem incorporating a hybrid circuit of the present invention is also provided.
    Type: Application
    Filed: October 27, 2003
    Publication date: April 28, 2005
    Inventors: Augustine Kuo, Tom Kwan, Sumant Ranganathan
  • Publication number: 20050036562
    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: Application
    Filed: August 25, 2004
    Publication date: February 17, 2005
    Inventors: Sumant Ranganathan, Tom Kwan
  • Publication number: 20050030108
    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: Application
    Filed: September 22, 2003
    Publication date: February 10, 2005
    Inventors: Ralph Duncan, Tom Kwan
  • Publication number: 20050017797
    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: Application
    Filed: August 16, 2004
    Publication date: January 27, 2005
    Inventors: Tom Kwan, Ralph Duncan, Frank Singor