Patents by Inventor David S. P. Ho

David S. P. 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: 7783275
    Abstract: A direct conversion satellite tuner is fully integrated on a common substrate. The integrated tuner receives an RF signal having a plurality of channels and down-converts a selected channel directly to baseband for further processing. The integrated tuner includes on-chip local oscillator generation, tunable baseband filters, and DC Offset cancellation. The integrated tuner can be implemented in a completely differential I/Q configuration for improved electrical performance. The entire direct conversion satellite tuner can be fabricated on a single semiconductor substrate using standard CMOS processing, with minimal off-chip components. The tuner configuration described herein is not limited to processing TV signals, and can be utilized to down-convert other RF signals to an IF frequency or baseband.
    Type: Grant
    Filed: October 13, 2006
    Date of Patent: August 24, 2010
    Assignee: Broadcom Corporation
    Inventors: Myles Wakayama, Dana Vincent Laub, Frank Carr, Afshin Mellati, David S. P. Ho, Hsiang-Bin Lee, Chun-Ying Chen, James Y. C. Chang, Lawrence M. Burns, Young Joon Shin, Patrick Pai, Iconomos A. Koullias, Ron Lipka, Luke Thomas Steigerwald, Alexandre Kral
  • Patent number: 7139547
    Abstract: A direct conversion satellite tuner is fully integrated on a common substrate. The integrated tuner receives an RF signal having a plurality of channels and down-converts a selected channel directly to baseband for further processing. The integrated tuner includes on-chip local oscillator generation, tunable baseband filters, and DC Offset cancellation. The integrated tuner can be implemented in a completely differential I/Q configuration for improved electrical performance. The entire direct conversion satellite tuner can be fabricated on a single semiconductor substrate using standard CMOS processing, with minimal off-chip components. The tuner configuration described herein is not limited to processing TV signals, and can be utilized to down-convert other RF signals to an IF frequency or baseband.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: November 21, 2006
    Assignee: Broadcom Corporation
    Inventors: Myles Wakayama, Dana Vincent Laub, Frank Carr, Afshin Mellati, David S. P. Ho, Hsiang-Bin Lee, Chun-Ying Chen, James Y. C. Chang, Lawrence M. Burns, Young Joon Shin, Patrick Pai, Iconomos A. Koullias, Ron Lipka, Luke Thomas Steigerwald, Alexandre Kral
  • Patent number: 6950049
    Abstract: The present invention is directed to a sigma-delta digital to analog converted (DAC) including a digital-sigma delta modulator, a decimation filter, and a multi-bit DAC. The digital sigma-delta modulator receives a digital input signal and produces a quantized digital signal therefrom. The decimation filter receives the quantized digital signal and produces a decimated digital signal therefrom. The multi-bit DAC receives the decimated digital signal and produces an analog output signal therefrom. The analog output signal is representative of the digital input signal.
    Type: Grant
    Filed: October 4, 2004
    Date of Patent: September 27, 2005
    Assignee: Broadcom Corporation
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller
  • Patent number: 6930626
    Abstract: Methods and apparatuses for spectrally shaping mismatch errors in a multi-bit digital to analog converter (DAC). In an embodiment, the multi-bit DAC is constructed from K separate multi-element sub-DACs, where K and the number of elements in each sub-DAC are each preferably greater than two. A received digital input code is split into a set of K sub-codes corresponding to the digital input code. The set of K sub-codes can have one of at least N different sub-code orders that specify an order of each of the K sub-codes with respect to one another, where N>2. A sum of the K sub-codes equals the digital input code. One of the at least N different sub-code orders is selected using a shuffling algorithm. Then, each sub-code in the set of K sub-codes is output in accordance with the selected sub-code order.
    Type: Grant
    Filed: July 20, 2004
    Date of Patent: August 16, 2005
    Assignee: Broadcom Corporation
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller, Eric Fogleman
  • Publication number: 20040252042
    Abstract: Methods and apparatuses for spectrally shaping mismatch errors in a multi-bit digital to analog converter (DAC). In an embodiment, the multi-bit DAC is constructed from K separate multi-element sub-DACs, where K and the number of elements in each sub-DAC are each preferably greater than two. A received digital input code is split into a set of K sub-codes corresponding to the digital input code. The set of K sub-codes can have one of at least N different sub-code orders that specify an order of each of the K sub-codes with respect to one another, where N>2. A sum of the K sub-codes equals the digital input code. One of the at least N different sub-code orders is selected using a shuffling algorithm. Then, each sub-code in the set of K sub-codes is output in accordance with the selected sub-code order.
    Type: Application
    Filed: July 20, 2004
    Publication date: December 16, 2004
    Inventors: Todd L. Brooks, David S.P. Ho, Kevin L. Miller, Eric Fogleman
  • Patent number: 6816097
    Abstract: The present invention is directed to a sigma-delta digital to analog converted (DAC) including a digital-sigma delta modulator, a decimation filter, and a multi-bit DAC. The digital sigma-delta modulator receives a digital input signal and produces a quantized digital signal therefrom. The decimation filter receives the quantized digital signal and produces a decimated digital signal therefrom. The multi-bit DAC receives the decimated digital signal and produces an analog output signal therefrom. The analog output signal is representative of the digital input signal.
    Type: Grant
    Filed: March 6, 2003
    Date of Patent: November 9, 2004
    Assignee: Broadcom Corporation
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller
  • Patent number: 6771199
    Abstract: Methods and apparatuses for spectrally shaping mismatch errors in a multi-bit digital to analog converter (DAC). In an embodiment, the multi-bit DAC is constructed from K separate multi-element sub-DACs, where K and the number of elements in each sub-DAC are each preferably greater than two. A received digital input code is split into a set of K sub-codes corresponding to the digital input code. The set of K sub-codes can have one of at least N different sub-code orders that specify an order of each of the K sub-codes with respect to one another, where N>2. A sum of the K sub-codes equals the digital input code. One of the at least N different sub-code orders is selected using a shuffling algorithm. Then, each sub-code in the set of K sub-codes is output in accordance with the selected sub-code order.
    Type: Grant
    Filed: April 8, 2003
    Date of Patent: August 3, 2004
    Assignee: Broadcom Corporation
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller, Eric Fogleman
  • Publication number: 20040021596
    Abstract: Methods and apparatuses for spectrally shaping mismatch errors in a multi-bit digital to analog converter (DAC). In an embodiment, the multi-bit DAC is constructed from K separate multi-element sub-DACs, where K and the number of elements in each sub-DAC are each preferably greater than two. A received digital input code is split into a set of K sub-codes corresponding to the digital input code. The set of K sub-codes can have one of at least N different sub-code orders that specify an order of each of the K sub-codes with respect to one another, where N>2. A sum of the K sub-codes equals the digital input code. One of the at least N different sub-code orders is selected using a shuffling algorithm. Then, each sub-code in the set of K sub-codes is output in accordance with the selected sub-code order.
    Type: Application
    Filed: April 8, 2003
    Publication date: February 5, 2004
    Applicant: Broadcom Corporation
    Inventors: Todd L. Brooks, David S.P Ho, Kevin L. Miller, Eric Fogleman
  • Patent number: 6628218
    Abstract: Methods and apparatuses for spectrally shaping mismatch errors in a multi-bit digital to analog converter (DAC). In an embodiment, the multi-bit DAC is constructed from K separate multi-element sub-DACs, where K and the number of elements in each sub-DAC are each preferably greater than two. A received digital input code is split into a set of K sub-codes corresponding to the digital input code. The set of K sub-codes can have one of at least N different sub-code orders that specify an order of each of the K sub-codes with respect to one another, where N>2. A sum of the K sub-codes equals the digital input code. One of the at least N different sub-code orders is selected using a shuffling algorithm. Then, each sub-code in the set of K sub-codes is output in accordance with the selected sub-code order.
    Type: Grant
    Filed: September 12, 2001
    Date of Patent: September 30, 2003
    Assignee: Broadcom Corporation
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller, Eric Fogleman
  • Publication number: 20030156051
    Abstract: The present invention is directed to a sigma-delta digital to analog converted (DAC) including a digital-sigma delta modulator, a decimation filter, and a multi-bit DAC. The digital sigma-delta modulator receives a digital input signal and produces a quantized digital signal therefrom. The decimation filter receives the quantized digital signal and produces a decimated digital signal therefrom. The multi-bit DAC receives the decimated digital signal and produces an analog output signal therefrom. The analog output signal is representative of the digital input signal.
    Type: Application
    Filed: March 6, 2003
    Publication date: August 21, 2003
    Applicant: Broadcom Corporation
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller
  • Patent number: 6577261
    Abstract: Methods and apparatuses for spectrally shaping mismatch errors in a multi-bit digital to analog converter (DAC). In an embodiment, a range signal is produced based on the digital input code. The range signal specifies which one of a plurality of ranges the digital input code is within. A density code is also produced, preferably, using a shuffling algorithm. The density code specifies a level within the range expressed by the range signal. The range signal and the density code are then combined to produce a plurality of sub-codes, a sum of the plurality of sub-codes equaling the digital input code.
    Type: Grant
    Filed: September 12, 2001
    Date of Patent: June 10, 2003
    Assignee: Broadcom Corporation
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller, Eric Fogleman
  • Patent number: 6531973
    Abstract: The present invention is directed to a sigma-delta digital to analog converted (DAC) including a digital-sigma delta modulator, a decimation filter, and a multi-bit DAC. The digital sigma-delta modulator receives a digital input signal and produces a quantized digital signal therefrom. The decimation filter receives the quantized digital signal and produces a decimated digital signal therefrom. The multi-bit DAC receives the decimated digital signal and produces an analog output signal therefrom. The analog output signal is representative of the digital input signal.
    Type: Grant
    Filed: September 12, 2001
    Date of Patent: March 11, 2003
    Assignee: Broadcom Corporation
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller
  • Publication number: 20020080053
    Abstract: The present invention is directed to a sigma-delta digital to analog converted (DAC) including a digital-sigma delta modulator, a decimation filter, and a multi-bit DAC. The digital sigma-delta modulator receives a digital input signal and produces a quantized digital signal therefrom. The decimation filter receives the quantized digital signal and produces a decimated digital signal therefrom. The multi-bit DAC receives the decimated digital signal and produces an analog output signal therefrom. The analog output signal is representative of the digital input signal.
    Type: Application
    Filed: September 12, 2001
    Publication date: June 27, 2002
    Inventors: Todd L. Brooks, David S.P. Ho, Kevin L. Miller
  • Publication number: 20020070887
    Abstract: Methods and apparatuses for spectrally shaping mismatch errors in a multi-bit digital to analog converter (DAC). In an embodiment, a range signal is produced based on the digital input code. The range signal specifies which one of a plurality of ranges the digital input code is within. A density code is also produced, preferably, using a shuffling algorithm. The density code specifies a level within the range expressed by the range signal. The range signal and the density code are then combined to produce a plurality of sub-codes, a sum of the plurality of sub-codes equaling the digital input code.
    Type: Application
    Filed: September 12, 2001
    Publication date: June 13, 2002
    Inventors: Todd L. Brooks, David S. P. Ho, Kevin L. Miller, Eric Fogleman
  • Publication number: 20020063647
    Abstract: Methods and apparatuses for spectrally shaping mismatch errors in a multi-bit digital to analog converter (DAC). In an embodiment, the multi-bit DAC is constructed from K separate multi-element sub-DACs, where K and the number of elements in each sub-DAC are each preferably greater than two. A received digital input code is split into a set of K sub-codes corresponding to the digital input code. The set of K sub-codes can have one of at least N different sub-code orders that specify an order of each of the K sub-codes with respect to one another, where N>2. A sum of the K sub-codes equals the digital input code. One of the at least N different sub-code orders is selected using a shuffling algorithm. Then, each sub-code in the set of K sub-codes is output in accordance with the selected sub-code order.
    Type: Application
    Filed: September 12, 2001
    Publication date: May 30, 2002
    Inventors: Todd L. Brooks, David S.P Ho, Kevin L. Miller, Eric Fogleman