Patents by Inventor Lawrence M. Burns

Lawrence M. Burns 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: 20040104771
    Abstract: A Variable Gain Amplifier (VGA) amplifies an input signal according to a gain, to produce an amplified signal. A detector module detects a power indicative of a power of the amplified signal. A comparator module compares the detected power to a high threshold, a low threshold and a target threshold intermediate the high and low thresholds. A controller module changes the gain of the VGA so as to drive the detected power in a direction toward the middle threshold when the comparator module indicates the detected power is not between the high and low thresholds.
    Type: Application
    Filed: January 30, 2003
    Publication date: June 3, 2004
    Applicant: Broadcom Corporation
    Inventors: Leonard Dauphinee, Lawrence M. Burns
  • Publication number: 20040105033
    Abstract: An amplifier assembly receives an input signal including multiple frequency channels. A first stage amplifier amplifies the input signal, to produce at an output thereof an amplified first signal including the multiple frequency channels. A plurality of second stage amplifiers have their respective inputs coupled to an output of the first stage amplifier. Each second stage amplifier amplifies the amplified first signal, to produce at its respective output a respective second amplified signal including the multiple frequency channels. The first stage amplifier and the second stage amplifiers are variable gain amplifiers, and are constructed on a common Integrated Circuit (IC) substrate.
    Type: Application
    Filed: January 30, 2003
    Publication date: June 3, 2004
    Applicant: Broadcom Corporation
    Inventors: Leonard Dauphinee, Lawrence M. Burns
  • Publication number: 20040066235
    Abstract: A low voltage current mirror circuit (also referred to as a bias circuit) for establishing a plurality of bias voltages from an input current supplied to an input terminal of the circuit includes an input stage, a current stage connected to the input stage, a feedback stage connected to the current stage, a reference bias stage connected to the feedback stage and the current stage. The circuit establishes first and second bias voltages suitable for biasing current sources of a first type, and third and fourth bias voltages suitable for biasing current sources of a second type complementary to the first type. The bias voltages track the input current over variations in at least one of process, temperature and power supply voltage.
    Type: Application
    Filed: October 7, 2003
    Publication date: April 8, 2004
    Applicant: Broadcom Corporation
    Inventor: Lawrence M. Burns
  • Patent number: 6714080
    Abstract: A low voltage current mirror circuit (also referred to as a bias circuit) for establishing a plurality of bias voltages from an input current supplied to an input terminal of the circuit includes an input stage, a current stage connected to the input stage, a feedback stage connected to the current stage, a reference bias stage connected to the feedback stage and the current stage. The circuit establishes first and second bias voltages suitable for biasing current sources of a first type, and third and fourth bias voltages suitable for biasing current sources of a second type complementary to the first type. The bias voltages track the input current over variations in at least one of process, temperature and power supply voltage.
    Type: Grant
    Filed: November 6, 2002
    Date of Patent: March 30, 2004
    Assignee: Broadcom Corporation
    Inventor: Lawrence M. Burns
  • Patent number: 6710704
    Abstract: Power supply current, sufficient to power a remote network device, is transmitted concurrently with a network data signal over a transmission line. A power-sourcing network device that can include a coupling circuit provides power and data to the remote network device. The coupling circuit can also be included in a stand-alone device. The remote network device (which can be a wireless access point) can separate the power signal from the data signal and use the power supply current to further process or retransmit the data signal. The power signal may be a low frequency relative to the frequency of the data signal, or it may be DC.
    Type: Grant
    Filed: October 28, 2002
    Date of Patent: March 23, 2004
    Assignee: 3Com Corporation
    Inventors: David A. Fisher, Lawrence M. Burns, Stephen E. Muther
  • Patent number: 6696893
    Abstract: An extended range variable gain amplifier is described. The variable gain capability is achieved by replacing differential pair amplifiers having an input signal with less attenuation with one having an input signal that is more attenuated. This replacement continues until only ten differential pair amplifiers are remaining. At this point, if less gain is desired, differential pair amplifiers are turned off, but are not replaced. A minimum number of amplifiers will remain on.
    Type: Grant
    Filed: December 16, 2002
    Date of Patent: February 24, 2004
    Assignee: Broadcom Corporation
    Inventors: Lawrence M. Burns, Leonard Dauphinee
  • Publication number: 20040021508
    Abstract: A system is provided for activating gain stages in an amplification module. The system includes an amplification module including a first group of amplifiers. Inverting output ports of each of the first group of amplifiers are coupled to a module inverting output terminal, and non-inverting output ports are coupled to a module non-inverting output terminal. A divider network is provided and is coupled to the input ports of the first group of amplifiers. A second group of amplifiers is also provided. Each amplifier of the second group corresponds to one of the amplifiers in the first group, has an inverting input port coupled to the second module inverting input terminal and to output ports of the divider network, and a non-inverting input port coupled to the second non-inverting input terminal.
    Type: Application
    Filed: July 31, 2003
    Publication date: February 5, 2004
    Applicant: Broadcom Corporation
    Inventors: Adel Fanous, Leonard Dauphinee, Lawrence M. Burns, Donald McMullin
  • Patent number: 6683498
    Abstract: A protection circuit for extending the dynamic range of an amplifier circuit is described. Off-chip impedances, such as inductors, cause the output of the circuit to swing above and below the bias voltage. A protection circuit is included, either on-chip or off-chip, to protect the integrated circuit components if there is a fault condition in either of the off-chip impedances.
    Type: Grant
    Filed: July 26, 2001
    Date of Patent: January 27, 2004
    Assignee: Broadcom Corporation
    Inventors: Lawrence M. Burns, Leonard Dauphinee
  • Patent number: 6670848
    Abstract: Provided is a system for implementing gain control in an amplification module comprising a first stage amplifier having a number of first stage input and output ports. The first stage amplifier is configured to provide first stage amplification to a received input signal and produce from the amplified input signal a number of output signals. Also included are a number of second stage amplifiers, each having second stage input and output ports, the second stage input ports being respectively coupled to the first stage output ports and being configured to receive the number of output signals. A gain control device is coupled to at least one from the group including the first stage input ports, the first stage output ports, and the second stage output ports. The gain control device is also configured to control a gain of at least one of the first stage amplifier and one or more of the number of second stage amplifiers.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: December 30, 2003
    Assignee: Broadcom Corporation
    Inventors: Adel Fanous, Leonard Dauphinee, Lawrence M. Burns, Donald McMullin
  • Patent number: 6662135
    Abstract: A method and apparatus for performing an operability test on a communications system device such as a cable modem is provided. The testing method comprises the steps of providing a set of output test data to the communications system device being tested, and generating an output signal with the device in a manner that is responsive to the output test data. In the case of a cable modem, the output signal is generated by the modem's modulator. The output signal is then provided as an input to a reflective mixer which generates a reflected signal in response to the output signal and directs it back into the communications system device being tested. The communications device can then use the reflected signal to generate a set of input test data that can be compared to the output test data to check the accuracy of the device's operation.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: December 9, 2003
    Assignee: 3Com Corporation
    Inventors: Lawrence M. Burns, Ravi Ramachandran
  • Patent number: 6657491
    Abstract: A system is provided for activating gain stages in an amplification module. The system includes an amplification module including a first group of amplifiers. Inverting output ports of each of the first group of amplifiers are coupled to a module inverting output terminal, and non-inverting output ports are coupled to a module non-inverting output terminal. A divider network is provided and is coupled to the input ports of the first group of amplifiers. A second group of amplifiers is also provided. Each amplifier of the second group corresponds to one of the amplifiers in the first group, has an inverting input port coupled to the second module inverting input terminal and to output ports of the divider network, and a non-inverting input port coupled to the second non-inverting input terminal.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: December 2, 2003
    Assignee: Broadcom Corporation
    Inventors: Adel Fanous, Leonard Dauphinee, Lawrence M. Burns, Donald McMullin
  • Publication number: 20030206063
    Abstract: Provided is a method and system for producing a drive signal for a current steering amplifier. An exemplary method comprises receiving a supply voltage signal and a differential input signal as a circuit input. A differential amplifier drive signal is produced in response to the received supply voltage signal, the received differential input signal, and the received differential control signal. The received differential input signal is adjusted to a value where magnitudes of negative and positive components of the differential control signal become equal to one another and are within a predetermined amount of a magnitude of the supply voltage signal.
    Type: Application
    Filed: May 6, 2003
    Publication date: November 6, 2003
    Inventors: Adel Fanous, Leonard Dauphinee, Lawrence M. Burns, Donald McMullin
  • Publication number: 20030164743
    Abstract: A varactor folding technique reduces noise in controllable electronic oscillators through the use of a series of varactors having relatively small capacitance. A folding circuit provides control signals to the varactors in a sequential manner to provide a relatively smooth change in the total capacitance of the oscillator. Consequently, effective control of the oscillator is achieved with accompanying reductions in oscillator noise such as flicker noise.
    Type: Application
    Filed: March 25, 2003
    Publication date: September 4, 2003
    Applicant: Broadcom Corporation
    Inventors: Ramon Alejandro Gomez, Lawrence M. Burns, Alexandre Kral
  • Publication number: 20030128085
    Abstract: A printed bandpass filter is mounted on a precision substrate to eliminate the need for post-fabrication tuning. The filter input is capacitively coupled to a series of quarter wavelength resonators and the filter output. The quarter wavelength resonators are printed as spirals to reduce filter size. The resonators define the bandpass characteristics of the filter. The filter also weakly couples the input signal to the filter output in a manner to cancel the signal image. Mechanical clips mitigate thermal stress on solder connections when the precision substrate mounted on a second printed circuit board.
    Type: Application
    Filed: January 9, 2002
    Publication date: July 10, 2003
    Applicant: Broadcom Corporation
    Inventors: Ramon A. Gomez, Lawrence M. Burns, Sung-Hsien Chang, Carl W. Pobanz
  • Publication number: 20030128084
    Abstract: A bandpass filter includes a plurality of resonators on a printed circuit board. An input pin is connected to a first resonator of the plurality of resonators. An output pin is connected to a second resonator of the plurality of resonators. The first and second resonators are magnetically coupled to each other. The first and second resonators are coupled to other resonators using mixed coupling. The other resonators are coupled to each other using electric coupling.
    Type: Application
    Filed: November 18, 2002
    Publication date: July 10, 2003
    Applicant: Broadcom Corporation
    Inventors: Sung-Hsien Chang, Ramon A. Gomez, Lawrence M. Burns, Carl W. Pobanz
  • Publication number: 20030122620
    Abstract: An extended range variable gain amplifier is described. The variable gain capability is achieved by replacing differential pair amplifiers having an input signal with less attenuation with one having an input signal that is more attenuated. This replacement continues until only ten differential pair amplifiers are remaining. At this point, if less gain is desired, differential pair amplifiers are turned off, but are not replaced. A minimum number of amplifiers will remain on.
    Type: Application
    Filed: December 16, 2002
    Publication date: July 3, 2003
    Applicant: Broadcom Corporation
    Inventors: Lawrence M. Burns, Leonard Dauphinee
  • Patent number: 6586996
    Abstract: Provided is a method and system for producing a drive signal for a current steering amplifier. An exemplary method comprises receiving a supply voltage signal and a differential input signal as a circuit input. A differential amplifier drive signal is produced in response to the received supply voltage signal, the received differential input signal, and the received differential control signal. The received differential input signal is adjusted to a value where magnitudes of negative and positive components of the differential control signal become equal to one another and are within a predetermined amount of a magnitude of the supply voltage signal.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: July 1, 2003
    Assignee: Broadcom Corporation
    Inventors: Adel Fanous, Leonard Dauphinee, Lawrence M. Burns, Donald McMullin
  • Patent number: 6563392
    Abstract: A varactor folding technique reduces noise in controllable electronic oscillators through the use of a series of varactors having relatively small capacitance. A folding circuit provides control signals to the varactors in a sequential manner to provide a relatively smooth change in the total capacitance of the oscillator. Consequently, effective control of the oscillator is achieved with accompanying reductions in oscillator noise such as flicker noise.
    Type: Grant
    Filed: December 14, 2000
    Date of Patent: May 13, 2003
    Assignee: Broadcom Corporation
    Inventors: Ramon Alejandro Gomez, Lawrence M. Burns, Alexandre Kral
  • Publication number: 20030076210
    Abstract: A multiple layer inductor has a first spiral conductive pattern disposed on a first surface; a second spiral conductive pattern disposed on a second surface; a continuing interconnection coupled to the first and second spiral conductive patterns; an interface coupled to the first and second spiral conductive patterns; and a conductive shield pattern disposed on a third surface that is adjacent to the second surface. The interface includes a first terminal disposed on the first surface that is coupled to the first spiral conductive pattern. The interface also includes a second terminal that is disposed on the first surface and coupled to said second spiral conductive pattern.
    Type: Application
    Filed: October 19, 2001
    Publication date: April 24, 2003
    Applicant: Broadcom Corporation
    Inventors: Ramon A. Gomez, Lawrence M. Burns
  • Publication number: 20030067353
    Abstract: A low voltage current mirror circuit (also referred to as a bias circuit) for establishing a plurality of bias voltages from an input current supplied to an input terminal of the circuit includes an input stage, a current stage connected to the input stage, a feedback stage connected to the current stage, a reference bias stage connected to the feedback stage and the current stage. The circuit establishes first and second bias voltages suitable for biasing current sources of a first type, and third and fourth bias voltages suitable for biasing current sources of a second type complementary to the first type. The bias voltages track the input current over variations in at least one of process, temperature and power supply voltage.
    Type: Application
    Filed: November 6, 2002
    Publication date: April 10, 2003
    Inventor: Lawrence M. Burns