Patents by Inventor Samuel D. Naffziger

Samuel D. Naffziger 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: 6466057
    Abstract: A new family of pseudo-NMOS static logic gates is provided that use feedback from a shared output node to enhance the response of and applicability of such static logic gates. In architecture, the feedback-induced pseudo-NMOS static (FIPNS) logic gate comprises (a) a pulldown network having one or more pulldown NMOS transistors for receiving one or more inputs, (b) a primary pullup network having one or more primary pullup PMOS transistors connected to the NMOS transistor network at a shared output node, which produces a gate output, and (c) a secondary pullup network having one or more secondary pullup PMOS transistors connected to the NMOS transistor network by way of an actuation mechanism, which causes actuation of the secondary pullup PMOS transistor(s) based upon feedback from the shared output node to thereby increase pullup drive strength relative to pulldown drive strength.
    Type: Grant
    Filed: January 21, 2000
    Date of Patent: October 15, 2002
    Assignee: Hewlett-Packard Company
    Inventor: Samuel D Naffziger
  • Publication number: 20020140467
    Abstract: A system and method are disclosed which utilize an on-chip oscillator to provide the appropriate clock frequency for components of the chip to manage power consumption by the chip. More specifically, in a preferred embodiment of the present invention, an on-chip oscillator is utilized to provide the clock frequency for the chip's core circuitry, and such oscillator can dynamically adjust such clock frequency to manage the chip's power consumption. Thus, such on-chip oscillator generates the processor clock instead of the usual synchronous, externally controlled clock generator. A preferred embodiment of the present invention utilizes a voltage controlled frequency oscillator to control the chip's clock frequency in order to dynamically manage power consumption by the chip. Such oscillator is preferably operable to adjust its output frequency based on the voltage supplied to such oscillator to effectively manage the chip's power consumption.
    Type: Application
    Filed: March 16, 2001
    Publication date: October 3, 2002
    Inventors: Samuel D. Naffziger, Don D. Josephson
  • Patent number: 6459304
    Abstract: The present invention provides a precharge circuit that has a first precharged node, a second precharged node, and a latch device. The first precharged node is charged to a high value during a precharge state. In response to a transition from the precharge state to an evaluate state, it either discharges to a low value or remains charged at its high value. The second precharged node has a value in the evaluate state that is based on the value of the first precharged node upon the circuit transitioning to the evaluate state. The latch device is connected to the second precharged node for latching this value in the evaluate state. With the latching device, this value is not affected by the first precharged node once the circuit has sufficiently transitioned to the evaluate state.
    Type: Grant
    Filed: February 21, 2000
    Date of Patent: October 1, 2002
    Assignee: Hewlett-Packard Company
    Inventors: Samuel D Naffziger, Jayen J Desai, Reid James Riedlinger
  • Publication number: 20020130712
    Abstract: A system and method are disclosed that utilize analog detection of an integrated circuit's (“chip's”) power consumption to enable power consumption management. On-chip circuitry may be utilized to detect analog electrical characteristics of the chip, such as its voltage, from which the chip's power consumption is determined. One embodiment utilizes on-chip circuitry to manage long-term, sustained power consumption of the chip, which encompasses power consumption for approximately a microsecond, as well as more extended time frames. Another embodiment utilizes on-chip circuitry to manage short-term power consumption of the chip, which encompasses power consumption for less than a microsecond (e.g., nanosecond time frame). A preferred embodiment implements both the circuitry for managing long-term power consumption and the circuitry for managing short-term power consumption.
    Type: Application
    Filed: March 16, 2001
    Publication date: September 19, 2002
    Inventors: Samuel D. Naffziger, Don D. Josephson
  • Publication number: 20020130695
    Abstract: A system and method are disclosed which provide an integrated circuit having a clock signal that is dynamically manipulated in response to detected events within the integrated circuit. In one embodiment, the chip includes event detection circuitry that monitors the operation of the chip and detects events that lead to a power disturbance therein. Circuitry may be included for detecting anticipated operation known to trigger an event, as well as for detecting unanticipated events. Additionally, clock manipulator circuitry is included to manipulate the chip's clock signal responsive detection of an event to enable the chip to cope with such event. In response to an event being detected, the clock manipulator circuitry may dynamically manipulate the clock signal in various manners, such as by altering the clock signal's duty cycle, delaying the occurrence of a transition of the clock signal, or altering the clock signal's frequency, as examples.
    Type: Application
    Filed: March 16, 2001
    Publication date: September 19, 2002
    Inventors: Don D. Jesephson, Samuel D. Naffziger
  • Patent number: 6448837
    Abstract: A shunt and shunt control circuit are connected to the wires of an on-chip terminated I/O bus. Each instance monitors the wire that it is connected to. If the wire has been pulled low by any device on the bus, the circuit does nothing. If, however, the wire was not pulled low, then current is shunted from the termination voltage supply to ground. The turn on and turn off rates for this shunt are matched to the ramps of current through the termination impedance of the bus. This makes the variability in current drawn from the termination voltage supply less data dependent.
    Type: Grant
    Filed: January 4, 2001
    Date of Patent: September 10, 2002
    Assignee: Hewlett-Packard Company
    Inventor: Samuel D. Naffziger
  • Patent number: 6446187
    Abstract: A cache with a translation lookaside buffer (TLB) that reduces the time required for retrieval of a physical address from the TLB when accessing the cache in a system that supports variable page sizing. The TLB includes a content addressable memory (CAM) containing the virtual page numbers corresponding to pages in the cache and a random access memory (RAM) storing the physical page numbers of the pages corresponding to the virtual page numbers in the CAM. The physical page number RAM stores a page mask along with the physical page numbers, and includes local multiplexers which perform virtual address bypassing of the physical page number when the page has been masked.
    Type: Grant
    Filed: February 19, 2000
    Date of Patent: September 3, 2002
    Assignee: Hewlett-Packard Company
    Inventors: Reid James Riedlinger, Samuel D Naffziger, Douglas J Cutter, Christopher Craig Seib
  • Publication number: 20020084826
    Abstract: A shunt and shunt control circuit are connected to the wires of an on-chip terminated I/O bus. Each instance monitors the wire that it is connected to. If the wire has been pulled low by any device on the bus, the circuit does nothing. If, however, the wire was not pulled low, then current is shunted from the termination voltage supply to ground. The turn on and turn off rates for this shunt are matched to the ramps of current through the termination impedance of the bus. This makes the variability in current drawn from the termination voltage supply less data dependent.
    Type: Application
    Filed: January 4, 2001
    Publication date: July 4, 2002
    Inventor: Samuel D. Naffziger
  • Patent number: 6377096
    Abstract: A static logic signal to dynamic logic interface that produces a monotonic output. An inverse of a dynamic logic evaluate clock is fed to the clock input of a transparent latch with clock and enable inputs. A delayed version of the inverse of the evaluate clock is generated by a delay element. The delayed inverse of the evaluate clock is fed to the enable input of the latch. The input to the latch comes from static logic and the output of the latch is fed to the dynamic logic. The net result is a latch that is open until the evaluate clock is instructing the dynamic logic to evaluate, and remains closed until a delay element delay time after the evaluate clock instructs the dynamic logic to reset.
    Type: Grant
    Filed: October 24, 2000
    Date of Patent: April 23, 2002
    Assignee: Hewlett-Packard Company
    Inventor: Samuel D. Naffziger
  • Patent number: 6366526
    Abstract: A static random access memory (SRAM) cell is provided that optimizes the density of memory cells in an array with the maximum speed possible in addressing the memory cells for reading and writing operations. The SRAM cell is divided into groups of SRAM arrays of cells with a centrally located distributed global decoder to address any individual memory cell in the SRAM array. The global decoder accepts an addressing input and outputs a signal for selecting an individual column of memory cells in the SRAM array. The global decoder also outputs a signal selecting an individual row of memory cells contained in the SRAM array. The global decoder may include logic to decode addressing bits to produce a group select signal. Thus, the global decoder is able to select any single memory cell in the SRAM cell for reading or writing specific logical states.
    Type: Grant
    Filed: February 21, 2001
    Date of Patent: April 2, 2002
    Inventors: Samuel D Naffziger, Donald R Weiss, John Wuu
  • Patent number: 6363006
    Abstract: A single-ended read, differential write CMOS SRAM cell has two inverters connected in a regenerative feedback circuit. Each inverter includes two complementary FETs. FETs of the same type in each inverter have differing gate widths and/or drive currents. The cell includes pass gate FETs having gate regions of approximately the same widths but differing lengths.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: March 26, 2002
    Assignee: Hewlett-Packard Company
    Inventors: Samuel D. Naffziger, Donald R. Weiss
  • Patent number: 6359830
    Abstract: An integrated circuit chip responds to clock waves having differing frequencies at different times. The chip includes a semiconductor memory cell having a write enable input terminal responsive to a write enable signal having first and second levels. The cell has a tendency to operate improperly in response to the first level of the write enable signal having an excessively long predetermined duration. A write enable signal source responds to the clock waves so that for clock waves having half cycles of duration less than the predetermined duration the first level of the write enable signal has durations approximately equal to the durations of the half cycles of these clock waves. For clock waves having half cycles of duration greater than the predetermined duration, the first level of the write enable signal has a duration substantially equal to the predetermined duration.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: March 19, 2002
    Assignees: Hewlett-Packard Company, Intel Corporation
    Inventors: Eric S Fetzer, Samuel D Naffziger, Preston J Renstrom
  • Publication number: 20020030512
    Abstract: The present invention provides a precharge circuit that has a first precharged node, a second precharged node, and a latch device. The first precharged node is charged to a high value during a precharge state. In response to a transition from the precharge state to an evaluate state, it either discharges to a low value or remains charged at its high value. The second precharged node has a value in the evaluate state that is based on the value of the first precharged node upon the circuit transitioning to the evaluate state. The latch device is connected to the second precharged node for latching this value in the evaluate state. With the latching device, this value is not affected by the first precharged node once the circuit has sufficiently transitioned to the evaluate state.
    Type: Application
    Filed: November 20, 2001
    Publication date: March 14, 2002
    Inventors: Samuel D. Naffziger, Jayen J. Desai, Reid James Riedlinger
  • Patent number: 6326829
    Abstract: CMOS integrated circuitry responsive to a clock source having an approximately 50% duty cycle includes a one shot having an input terminal connected to be responsive to the clock wave source. The one shot derives a pulse train in response to cycles of the clock. Each pulse in the pulse train has a duration substantially less than one-half cycle of the clock wave, is initiated in response to and during a clock wave transition, and persists for a period after the transition has been completed. Latches respond to plural data signals and the pulse train so each latch is activated to be responsive to its associated data signal only during the pulses.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: December 4, 2001
    Assignee: Hewlett-Packard Company
    Inventor: Samuel D Naffziger
  • Patent number: 6323714
    Abstract: A system and method for actively deskewing synchronous clocks in a VLSI circuit by introducing a controllable delay unit within a local clock buffer within each of a number of circuit zones and applying a controllable delay at each of the local clock buffers in response to a phase comparison of clock signals from one or more adjacent clock zones. The system can be added to any of a number of various clock distribution networks on a VLSI circuit through the introduction of controllable clock zone buffers and localized phase comparators. By adjusting each localized clock buffer delay unit in response to measured clock signal phase differences from adjacent circuit zones, clock skew problems can be minimized across various clock zones on a VLSI circuit.
    Type: Grant
    Filed: February 3, 2000
    Date of Patent: November 27, 2001
    Assignee: Hewlett-Packard Company
    Inventors: Samuel D Naffziger, Eugene Z Berta, Gerard M Blair, James Steven Wells
  • Publication number: 20010043486
    Abstract: A single-ended read, differential write CMOS SRAM cell has two inverters connected in a regenerative feedback circuit. Each inverter includes two complementary FETs. FETs of the same type in each inverter have differing gate widths and/or drive currents.
    Type: Application
    Filed: March 19, 2001
    Publication date: November 22, 2001
    Inventors: Samuel D. Naffziger, Donald R. Weiss
  • Patent number: 6313675
    Abstract: The present invention provides an improved, efficient DLL design. In one embodiment, it includes a voltage controlled delay line, a phase comparator, and a dynamic bias source. The delay line has an associated delay that is controllably adjusted by a received control signal. The delay line also has an input for receiving a reference signal and one or more outputs for providing one or more delayed versions of the reference signal. The phase comparator is operably connected to the delay line in a closed loop fashion for controlling the control signal based on the phase difference between the reference signal and one of the one or more delayed reference signal versions to cause the delay line to generate an output delayed reference signal that is in synch. with the reference signal but delayed from it by a predetermined quantity. The dynamic bias source provides power to the delay line as it is needed so that the control signal is not adversely affected by changes in the delay lines power demands.
    Type: Grant
    Filed: February 21, 2000
    Date of Patent: November 6, 2001
    Assignee: Hewlett-Packard Company
    Inventor: Samuel D Naffziger
  • Patent number: 6301186
    Abstract: An SRAM that has a column clear function with only three vertical lines and six total lines across a cell and a method of operating that cell and an array of those cells. Instead of two bit lines per port and two access devices per port as in a traditional SRAM cell, one bit line and one access device per port is used. In addition, one additional bit line, one additional word line, and two devices in series are used to perform the column clear operation and complete a write operation. The cell is operated by performing write operations using a two step process. To perform a write, each cell in a row to be written is preset during a first step. Then, each cell that is to have a zero written to it is cleared using the additional bit line and additional word line to address the cells to be cleared. A column of cells may be cleared by enabling all the rows for clearing, then asserting column clear control signals for each of the columns in the array to be cleared.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: October 9, 2001
    Assignee: Hewlett-Packard Company
    Inventor: Samuel D. Naffziger
  • Patent number: 6292041
    Abstract: Disclosed are circuits and methods that prevent failure modes in related circuits. The circuit processes a pulse for use with a related circuit. The circuit comprises a timer and one or more logic gates. The timer produces an output in a given state if the duration of the pulse reaches a predetermined amount of time. The predetermined amount of time is related to a parameter of the related circuit. The one or more logic gates have an output that is the same as the pulse unless and until the output of the timer is in the given state, at which time, the output of the one or more logic gates is forced to a non-pulsed state. Preferably, the parameter is a subthreshold leakage rate across an FET. The method is used with a circuit in which leakage can occur at a first rate. The method comprises the step of sensing a condition that prompts leakage to occur in the circuit. In response to the sensing step, the method produces a related leakage at a faster rate than the first rate.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: September 18, 2001
    Assignee: Hewlett Packard Company
    Inventor: Samuel D Naffziger
  • Patent number: 6281710
    Abstract: An integrated circuit chip includes a domino logic gate, circuitry for selectively latching a logic output signal of the gate and an enable source for the gate. The enable source and gate positions on the chip and a clock driving the chip has a frequency such that the enable signal arrives late at the logic gate during the evaluate phase of each clock cycle. The circuitry for selectively latching is constructed so that the domino logic gate is evaluated or latched during the same clock cycle that the enable signal is derived despite the aforementioned positions and frequency.
    Type: Grant
    Filed: December 17, 1999
    Date of Patent: August 28, 2001
    Assignee: Hewlett-Packard Company
    Inventors: Christopher Allan Poirier, Samuel D Naffziger