Patents by Inventor Stacy J. Garvin

Stacy J. Garvin 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: 7539473
    Abstract: A circuit design, method, and system for tracking VCO calibration without requiring an over-designed divider as in conventional implementation. A filter reset component is added to the inputs of the VCO. A process step is added to the calibration mechanism/process that shorts the filter nodes and thus centers the frequency of the VCO before stepping from one frequency band to the next.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: May 26, 2009
    Assignee: International Business Machines Corporation
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin, Vernon R. Norman
  • Patent number: 7486127
    Abstract: A circuit device having a transistor-based switch topology that substantially eliminates the possibility of latchup of the device. A series-connected low voltage threshold (LVT) N-channel transistor and a pull-up resistor are coupled across a switching (P-channel) transistor so that an integral body connection is provided for the switching transistor, which connects the body of the switching transistor to a node between the pull-up resistor and source terminal of the LVT transistor. The LVT transistor is connected with its gate and drain terminal connected to the output terminal of the switching transistor. The resistor is connected at its other end to the power supply side terminal of the switching transistor. The addition of these components in the particular configuration allows the body connection of the switching transistor to be automatically switched to the highest potential diffusion node.
    Type: Grant
    Filed: August 7, 2007
    Date of Patent: February 3, 2009
    Assignee: International Business Machines Corporation
    Inventors: Hayden C. Cranford, Stacy J. Garvin, Todd M. Rasmus
  • Patent number: 7279950
    Abstract: A differential clock signal gating method and system is provided, wherein a clock buffer circuit control path develops a clock gating signal with a timing relationship to a clock signal. The clock gating signal gates a buffer on the clock buffer circuit controlled path in communication with the clock signal responsive to a first clock signal pulse negative half. The buffer provides second and successive clock signal pulses occurring immediately and sequentially after the first clock signal pulse as a buffer clock signal output to a second buffer stage in a second stage clock path, each having the nominal clock amplitude and the nominal clock pulse width of the clock signal without jitter.
    Type: Grant
    Filed: September 27, 2005
    Date of Patent: October 9, 2007
    Assignee: International Business Machines Corporation
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin, Vernon R. Norman, Samuel T. Ray, Wayne A. Utter
  • Patent number: 7268613
    Abstract: A circuit device having a transistor-based switch topology that substantially eliminates the possibility of latchup of the device. A series-connected low voltage threshold (LVT) N-channel transistor and a pull-up resistor are coupled across a switching (P-channel) transistor so that an integral body connection is provided for the switching transistor, which connects the body of the switching transistor to a node between the pull-up resistor and source terminal of the LVT transistor. The LVT transistor is connected with its gate and drain terminal connected to the output terminal of the switching transistor. The resistor is connected at its other end to the power supply side terminal of the switching transistor. The addition of these components in the particular configuration allows the body connection of the switching transistor to be automatically switched to the highest potential diffusion node.
    Type: Grant
    Filed: October 31, 2005
    Date of Patent: September 11, 2007
    Assignee: International Business Machines Corporation
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin, Todd M. Rasmus
  • Patent number: 7042277
    Abstract: Aspects for reducing jitter in a PLL of a high speed serial link include examining at least one parameter related to performance of a voltage controlled oscillator (VCO) in the PLL, and controlling adjustment of a supply voltage to the VCO based on the examining. A regulator control circuit performs the examining and controlling.
    Type: Grant
    Filed: October 14, 2003
    Date of Patent: May 9, 2006
    Assignee: International Business Machines Corporation
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin, Vernon R. Norman, Todd M. Rasmus
  • Patent number: 6977558
    Abstract: A self-adaptive voltage regulator for a phase-locked loop is disclosed. The phase-locked loop includes a phase detector, a charge pump, a low pass filter, and a voltage control oscillator, wherein the low pass filter inputs a control voltage to a voltage controlled oscillator for generation of an output clock. According to the method and system disclosed herein, the self-adaptive voltage regulator is coupled to an output of the low pass filter for sensing the control voltage during normal operation of the phase-locked loop, and for dynamically adjusting the supply voltage, which is input to the voltage controlled oscillator in response to the control voltage, such that the phase-locked loop maintains the control voltage within a predefined range of a reference voltage.
    Type: Grant
    Filed: August 28, 2003
    Date of Patent: December 20, 2005
    Assignee: International Busines Machines Corporation
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin, Vernon R. Norman, Todd M. Rasmus, Peter R. Seidel
  • Patent number: 6900703
    Abstract: The present invention describes aspects of adjusting a frequency range of a delay cell of a VCO. The aspects include providing a CMOS latch of predetermined gain, and altering transconductance in the CMOS latch to alter a frequency range of the CMOS latch without altering the predetermined gain. The alteration of transconductance includes coupling at least one pair of series connected transistors in parallel with each switching device of the CMOS latch.
    Type: Grant
    Filed: August 20, 2003
    Date of Patent: May 31, 2005
    Assignee: International Business Machines Corporation
    Inventor: Stacy J. Garvin
  • Patent number: 6031394
    Abstract: A low voltage CMOS circuit and method provide output current ability meeting multimode requirements of high voltage off-chip drivers while protecting the CMOS devices from various breakdown mechanisms. The circuit and method utilize intermediate voltages between two power rails and voltage division techniques to limit the voltages to acceptable limits for drain-to-source, gate-to-drain, and gate-to-source of CMOS devices in any chosen technology. The circuit comprises first and second CMOS cascode chains connected between a high voltage power rail, e.g 5 volt and a reference potential power rail, e.g. ground. Each CMOS cascode chain comprises first and second p-type MOS devices in series with first and second n-type MOS devices. An input circuit is coupled to a node at the midpoint of the first CMOS cascode chain. A bias voltage, typically 3.3 volts is connected to the NMOS devices in the first and CMOS cascode chains.
    Type: Grant
    Filed: January 8, 1998
    Date of Patent: February 29, 2000
    Assignee: International Business Machines Corporation
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin, Geoffrey B. Stephens
  • Patent number: 5396449
    Abstract: A content addressable memory in accordance with the present invention includes a number of bistable memory cells having as inputs thereto first and second bit lines and an address line, and a COMPARE circuit connected to each of the memory cells so as to provide the COMPARE function without loading the first and second bit lines and including means for inhibiting current flow when a miscompare occurs.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: March 7, 1995
    Assignee: International Business Machines Corporation
    Inventors: Francois I. Atallah, Stacy J. Garvin, David W. Nuechterlein
  • Patent number: 4752699
    Abstract: A level selectable FET voltage generation system is described. The system includes a single charge pump controlled by multiple feedback paths and a powerdown circuit. Each feedback path contains a capacitor divider network, a sense amplifier with a compensating voltage reference and a timer which periodically resets the capacitor divider network to insure sensing accuracy. The powerdown circuit and a selected feedback path provides a desired voltage level at the output of the charge pump.
    Type: Grant
    Filed: December 19, 1986
    Date of Patent: June 21, 1988
    Assignee: International Business Machines Corp.
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin, Wendy K. Hodgin, John M. Mullen
  • Patent number: 4638464
    Abstract: A voltage generating system provides a plurality of different voltages for powering a dynamic nonvolatile random access memory (NVRAM) chip. The voltage generating system includes a pair of charge pumps. Each charge pump is coupled to a controller that senses the voltage level at the output of the charge pump and generates an enabling signal when said voltage is at a predetermined value. The signal activates a power down circuit which adjusts the charge pump output to a desired voltage level. A programmable oscillator provides the clocking signals for the controller. The charge pumps and programmable oscillators are periodically deactivated. As a result, the overall power consumption of the chip is reduced.
    Type: Grant
    Filed: November 14, 1983
    Date of Patent: January 20, 1987
    Assignee: International Business Machines Corp.
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin
  • Patent number: 4536720
    Abstract: A programmable oscillator is provided for use on an integrated circuit chip. The oscillator includes a plurality of inverter delay stages connected in tandem between an input and an output node. A single FET device couples a node common to all of the inverter delay stages to a ground potential. Another FET device controls the input node. When a logic enabling signal is appropriately applied to the FET devices, the oscillator is controlled so that internal nodes of the oscillator float high when it is off and no energy is dissipated. In addition, the amount of delays between the delay stages and the input stage of the load is such that the load supplies the greater ratio of delays. This ensures that the oscillator's frequency of oscillation tracks the switching speed of the load.
    Type: Grant
    Filed: November 14, 1983
    Date of Patent: August 20, 1985
    Assignee: International Business Machines Corporation
    Inventors: Hayden C. Cranford, Jr., Stacy J. Garvin