Patents by Inventor John R. Francis

John R. Francis 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: 20230040489
    Abstract: An amplifier with temperature compensation where the amplifier has transistors configured to amplify a received signal to create an amplified signal. The amplifier gain changes over temperature. A gain control circuit, connected to the amplifier, that adjusts the amplifier gain responsive to a gain control signal. A temperature compensation circuit includes numerous elements. A constant current source that generates a constant current which is used to create a constant voltage. A temperature dependent current source that generates a temperature dependent current which is used to create a temperature dependent voltage, such that the temperature dependent current source has an inverse temperature dependance as compared to the amplifier. An operational amplifier compares the constant voltage to the temperature dependent voltage and generates an offset signal which varies over temperature. A gated buffer is configured to receive the offset signal and responsive thereto, selectively modify the gain control signal.
    Type: Application
    Filed: August 9, 2021
    Publication date: February 9, 2023
    Inventor: John R. Francis
  • Patent number: 6034554
    Abstract: An improved phase detector for detecting the difference between an information signal and a clock signal is provided. The information signal is divided into a plurality of N divided signals, the data rate of each divided signal being the data rate of the information signal divided by N. A plurality of N variable width difference pulse signals are generated each being responsive to the phase difference between a divided signal and the clock signal. One or more fixed width reference pulse signals having a width proportional to one-half clock period are also generated. A phase error signal is then provided in response to the N difference pulse signals and the one or more reference pulse signals. Preferably, N is equal to 2.sup.M, where M is a positive integer greater than or equal to one.
    Type: Grant
    Filed: April 2, 1998
    Date of Patent: March 7, 2000
    Assignee: Gennum Corporation
    Inventors: John R. Francis, Atul Gupta
  • Patent number: 5541556
    Abstract: A control circuit for use with a phase locked loop in a digital video receiver. The digital receiver accepts a serial digital input signal which can comprise composite or component video signals. The phase locked loop comprises a phase detector, a loop filter, and a voltage controlled oscillator (VCO) and includes a divide-by-two modulus divider coupled to the output of the VCO. The VCO has an oscillation frequency control port and the divider has a frequency select port. The control circuit includes an automatic fine tuning and frequency sweeping stage which is coupled to the output of the loop filter and the oscillation frequency control port. The tuning and frequency stage provides temperature drift correction for the VCO. In addition, the tuning and frequency stage "sweeps" the oscillation frequency of the VCO to aid in "locking" the phase locked loop to the phase or frequency of the input signal. Once locked, timing signals and digital data can be extracted from the input signal.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: July 30, 1996
    Assignee: Gennum Corporation
    Inventor: John R. Francis
  • Patent number: 5357220
    Abstract: An emitter-coupled oscillator circuit suitable for monolithic integration.
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: October 18, 1994
    Assignee: Gennum Corporation
    Inventor: John R. Francis
  • Patent number: 5212414
    Abstract: The switch has a cross-point. The cross-point has an input buffer, a level shift and an output buffer. The input and output buffers are BJT's, the level shift is two diode connected BJT's. The voltage drops across the buffers are designed to match the voltage drops across the diodes. The cross-point is enabled by a current source forcing current through the diodes. The matching of the voltage drops is effected by the Early voltage of the BJT's as they are operated at different V.sub.ce 's. An Early voltage determinator determines the effect of the Early voltage and adjusts the current flowing from the current source to force differing bias currents through the input buffer and the diodes to make the sum of the V.sub.be 's of each more independent of Early voltage. The output impedance of the current source and the impedance of the cross-point form a resistor-capacitor network. Where the f.sub..tau.
    Type: Grant
    Filed: September 26, 1990
    Date of Patent: May 18, 1993
    Assignee: Gennum Corporation
    Inventor: John R. Francis
  • Patent number: 5169653
    Abstract: A label transfer assembly providing for in-mold labeling of blow molded articles in blow molding machinery. A label carrier is utilized which includes means for individually receiving labels from a label storage magazine. Once loaded with labels, the label carrier is moved to a position adjacent a placement assembly. The labels are removed from the carrier by the placement assembly which includes arms that transfer the labels to positions in mold cavities in the machinery. During molding, the labels will become fused to the surfaces of the blow molded articles.
    Type: Grant
    Filed: July 22, 1991
    Date of Patent: December 8, 1992
    Assignee: Hoover Universal, Inc.
    Inventors: Dennis J. Tate, John R. Francis
  • Patent number: 4065722
    Abstract: Demodulation of an ac signal that has been modulated by discrete changes in its amplitude, frequency or phase, is effected by first feeding the modulated ac signal through an amplitude limiter and hence through a bandpass filter tuned to a preselected frequency of the ac signal. The resulting bandpass-filtered ac signal defines a variable amplitude envelope which varies in response to amplitude, frequency or phase modulations of the input ac signal. Amplitude variations of the envelope of the bandpass-filtered ac signal are detected by a switching circuit whose operation has been termed "self-synchronous," because it is synchronized to the frequency of the ac signal prior to the passage of the ac signal through the bandpass filter. More particularly, the switching circuit is opened and closed in response to the ac signal appearing at the input to the bandpass filter, to cause alternate, like-polarity half cycles of the bandpass-filtered ac signal to be selectively conducted to a low-pass filter.
    Type: Grant
    Filed: December 27, 1976
    Date of Patent: December 27, 1977
    Assignee: Glenayre Electronics, Ltd.
    Inventor: John R. Francis