Patents by Inventor David R. Welland

David R. Welland 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: 10488269
    Abstract: A method includes alternately coupling a selected one of a plurality of current sources and two or more of the plurality of current sources to a first terminal of a bipolar device during first and second phases of a modulator cycle of a plurality of modulator cycles. The method further includes providing sampled voltages from the first terminal of the bipolar device to a modulator to produce a modulator output signal, filtering the modulator output signal to produce a filtered output signal using a back-end filter having an impulse response, and determining a temperature in response to the filtered output signal.
    Type: Grant
    Filed: December 29, 2015
    Date of Patent: November 26, 2019
    Assignee: Silicon Laboratories Inc.
    Inventor: David R Welland
  • Patent number: 9870103
    Abstract: A controller for a capacitive touch screen or the like includes a touch resolve subsystem and a processor. The touch resolve subsystem, when activated, measures a plurality of capacitance values using a plurality of input pins. The processor uses the plurality of capacitance values at each of a plurality of values of a parameter to create an interference map.
    Type: Grant
    Filed: January 3, 2012
    Date of Patent: January 16, 2018
    Assignee: Silicon Laboratories Inc.
    Inventors: Vadim Konradi, Parker Dorris, Michael Franklin, David R. Welland
  • Patent number: 9726696
    Abstract: In one form, a reference circuit includes a measurement circuit and a determination circuit. The measurement circuit has an output for providing a ratio of a difference in base-to-emitter voltage (VBE) of a bipolar device at different current densities to a VBE of the bipolar device at a first current density. The determination circuit has an input coupled to the measurement circuit, and an output for providing a digital value of a parameter in response to the ratio. In another form, the reference circuit further includes a voltage generation circuit having an input coupled to the determination circuit, and an output, for modulating an analog voltage using the digital value to provide a reference voltage to the output, wherein the reference voltage is temperature compensated over a temperature range.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: August 8, 2017
    Inventors: Matthew Powell, David R. Welland
  • Patent number: 9727159
    Abstract: A controller for a capacitive touch screen includes a touch resolve subsystem and a processor. The touch resolve subsystem, in response to a trigger input, measures a plurality of capacitance values using a plurality of input pins. The processor controls the touch resolve subsystem to acquire a baseline capacitance in a calibration mode, to acquire a frame comprising the plurality of capacitance values in a normal operation mode, and to update the baseline capacitance to a new baseline capacitance in the normal operation mode in response to the frame without entering the calibration mode.
    Type: Grant
    Filed: January 3, 2012
    Date of Patent: August 8, 2017
    Inventors: Vadim Konradi, Parker Dorris, Michael Franklin, David R. Welland
  • Publication number: 20160131536
    Abstract: A method includes alternately coupling a selected one of a plurality of current sources and two or more of the plurality of current sources to a first terminal of a bipolar device during first and second phases of a modulator cycle of a plurality of modulator cycles. The method further includes providing sampled voltages from the first terminal of the bipolar device to a modulator to produce a modulator output signal, filtering the modulator output signal to produce a filtered output signal using a back-end filter having an impulse response, and determining a temperature in response to the filtered output signal.
    Type: Application
    Filed: December 29, 2015
    Publication date: May 12, 2016
    Applicant: Silicon Laboratories Inc.
    Inventor: David R. Welland
  • Patent number: 9250137
    Abstract: A method includes alternately coupling a selected one of a plurality of current sources and two or more of the plurality of current sources to a first terminal of a bipolar device during first and second phases of a modulator cycle of a plurality of modulator cycles. The method further includes providing sampled voltages from the first terminal of the bipolar device to a modulator to produce a modulator output signal, filtering the modulator output signal to produce a filtered output signal using a back-end filter having an impulse response, and determining a temperature in response to the filtered output signal.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: February 2, 2016
    Assignee: Silicon Laboratories Inc.
    Inventor: David R. Welland
  • Patent number: 9095041
    Abstract: A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: July 28, 2015
    Assignee: Silicon Laboratories Inc.
    Inventors: David R. Welland, Donald A. Kerth, Caiyi Wang
  • Publication number: 20140086278
    Abstract: A method includes alternately coupling a selected one of a plurality of current sources and two or more of the plurality of current sources to a first terminal of a bipolar device during first and second phases of a modulator cycle of a plurality of modulator cycles. The method further includes providing sampled voltages from the first terminal of the bipolar device to a modulator to produce a modulator output signal, filtering the modulator output signal to produce a filtered output signal using a back-end filter having an impulse response, and determining a temperature in response to the filtered output signal.
    Type: Application
    Filed: September 21, 2012
    Publication date: March 27, 2014
    Inventor: David R. Welland
  • Publication number: 20140084899
    Abstract: In one form, a reference circuit includes a measurement circuit and a determination circuit. The measurement circuit has an output for providing a ratio of a difference in base-to-emitter voltage (VBE) of a bipolar device at different current densities to a VBE of the bipolar device at a first current density. The determination circuit has an input coupled to the measurement circuit, and an output for providing a digital value of a parameter in response to the ratio. In another form, the reference circuit further includes a voltage generation circuit having an input coupled to the determination circuit, and an output, for modulating an analog voltage using the digital value to provide a reference voltage to the output, wherein the reference voltage is temperature compensated over a temperature range.
    Type: Application
    Filed: December 21, 2012
    Publication date: March 27, 2014
    Inventors: Matthew Powell, David R. Welland
  • Patent number: 8648653
    Abstract: A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another.
    Type: Grant
    Filed: December 31, 2009
    Date of Patent: February 11, 2014
    Assignee: Silicon Laboratories Inc.
    Inventors: David R. Welland, Donald A. Kerth, Caiyi Wang
  • Publication number: 20130169583
    Abstract: A controller for a capacitive touch screen or the like includes a touch resolve subsystem and a processor. The touch resolve subsystem, when activated, measures a plurality of capacitance values using a plurality of input pins. The processor uses the plurality of capacitance values at each of a plurality of values of a parameter to create an interference map.
    Type: Application
    Filed: January 3, 2012
    Publication date: July 4, 2013
    Inventors: Vadim Konradi, Parker Dorris, Michael Franklin, David R. Welland
  • Publication number: 20130169584
    Abstract: A controller for a capacitive touch screen includes a touch resolve subsystem and a processor. The touch resolve subsystem, in response to a trigger input, measures a plurality of capacitance values using a plurality of input pins. The processor controls the touch resolve subsystem to acquire a baseline capacitance in a calibration mode, to acquire a frame comprising the plurality of capacitance values in a normal operation mode, and to update the baseline capacitance to a new baseline capacitance in the normal operation mode in response to the frame without entering the calibration mode.
    Type: Application
    Filed: January 3, 2012
    Publication date: July 4, 2013
    Inventors: Vadim Konradi, Parker Dorris, Michael Franklin, David R. Welland
  • Patent number: 8421529
    Abstract: A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another.
    Type: Grant
    Filed: December 31, 2009
    Date of Patent: April 16, 2013
    Assignee: Silicon Laboratories Inc.
    Inventors: David R. Welland, Donald A. Kerth, Caiyi Wang
  • Publication number: 20120169659
    Abstract: A method for interfacing with a capacitive touch screen is disclosed. The method includes charging an internal capacitor in the touch screen, which internal capacitor is disposed proximate a fixed location on the touch screen and is capable of changing in response to a touch at that location on the touch screen. After charging, value of the charge on the internal capacitor is determined in a manner to reduce effects of interference.
    Type: Application
    Filed: December 22, 2011
    Publication date: July 5, 2012
    Inventor: David R. Welland
  • Patent number: 8154336
    Abstract: A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: April 10, 2012
    Assignee: Silicon Laboratories Inc.
    Inventors: David R. Welland, Donald A. Kerth, Caiyi Wang
  • Patent number: 7884666
    Abstract: A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: February 8, 2011
    Assignee: Silicon Laboratories Inc.
    Inventors: David R. Welland, Donald A. Kerth, Caiyi Wang
  • Patent number: 7835706
    Abstract: An RF transmitter (104) includes a shared local oscillator circuit (126), transmit path circuitry (120, 122, 124), a divider (134), and a lowpass filter (322). The shared local oscillator circuit (126) generates a shared LO signal (116). The transmit path circuitry (120, 122, 124) mixes a baseband signal (107) and an IF mixing signal (116) to provide an IF signal (112), and converts the IF signal (112) to an RF transmit signal (105) at a desired frequency using an RF mixing signal received at a mixing input thereof. The divider (134) divides the shared LO signal (116) to provide an unfiltered RF mixing signal. The lowpass filter (322) has an input for receiving the unfiltered RF mixing signal, and an output coupled to the mixing input of the transmit path circuitry (120, 122, 124) for providing the RF mixing signal.
    Type: Grant
    Filed: September 12, 2005
    Date of Patent: November 16, 2010
    Assignee: Silicon Laboratories, Inc.
    Inventors: David R. Welland, Ramkishore Ganti, CaiYi Wang
  • Patent number: 7804364
    Abstract: A method and apparatus is provided for detecting the output power of a power amplifier. The output power is detected by detecting the absolute values of the voltage and current at the output of the amplifier and mixing the detected voltage and current to generate a signal related to the output power.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: September 28, 2010
    Assignee: Black Sand Technologies, Inc.
    Inventors: Timothy J. Dupuis, David R. Welland, Susanne A. Paul, Ali M. Niknejad
  • Publication number: 20100102876
    Abstract: A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another.
    Type: Application
    Filed: December 31, 2009
    Publication date: April 29, 2010
    Inventors: David R. Welland, Donald A. Kerth, Caiyi Wang
  • Publication number: 20100102858
    Abstract: A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another.
    Type: Application
    Filed: December 31, 2009
    Publication date: April 29, 2010
    Inventors: David R. Welland, Donald A. Kerth, Caiyi Wang