Including Time Indicating Means Actuated By Voltage Or Electrical Charge Patents (Class 368/121)
  • Patent number: 10943876
    Abstract: An attack on an integrated circuit using a beam of electrically charged particles is detected by collecting charges due to the attack using at least one electrically conductive body that is electrically coupled to the floating gate of a state transistor. Prior to the attack, the state transistor is configured to confer an initial threshold voltage. The collected charges passed to the floating gate cause a modification of the threshold voltage of the state transistor. Detection of the attack is made by determining that the threshold voltage of the state transistor is different from the initial threshold voltage.
    Type: Grant
    Filed: July 24, 2019
    Date of Patent: March 9, 2021
    Assignee: STMicroelectronics (Rousset) SAS
    Inventors: Fabrice Marinet, Pascal Fornara
  • Patent number: 10089164
    Abstract: A microcontroller may comprise a central processing unit coupled with a plurality of peripheral devices through a system bus; and a watchdog timer unit receiving a clear watchdog signal and being configured to generate a watchdog timeout signal for resetting the microcontroller, wherein the watchdog timer unit is further configured to define a first and a second watchdog timeout period through a first and a second timer, respectively, further having logic to select the first or the second timer, wherein the clear watchdog signal resets the first and second timer.
    Type: Grant
    Filed: February 25, 2016
    Date of Patent: October 2, 2018
    Assignee: MICROCHIP TECHNOLOGY INCORPORATED
    Inventor: Keith Curtis
  • Patent number: 8458705
    Abstract: Provided is a method and apparatus for managing a schedule of a terminal based on a local time. It is possible to prevent schedule information from a schedule of a terminal from being repeatedly processed or from being missed, when the local time changes due to the movement of the terminal into another time zone or due to daylight saving time. It is also possible to manage a schedule by determining if the schedule has changed during a period between a time before the change and the changed time.
    Type: Grant
    Filed: December 17, 2007
    Date of Patent: June 4, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hae-Young Jun, Ji-Eun Keum, Wuk Kim
  • Patent number: 7414517
    Abstract: A radio frequency identification transponder includes a power supply and a dynamic memory array that stores data. When power from the power supply ceases, the data in the dynamic memory array is validly maintained for a predetermined period of time. The dynamic memory array is responsive to an interrogating signal for selectively updating the data. A radio frequency identification transponder includes a signal processor that extracts an identifier from the interrogation signal and is responsive to the identifier and the stored data to determine whether some or all of the identifier is stored in the dynamic memory array.
    Type: Grant
    Filed: June 26, 2007
    Date of Patent: August 19, 2008
    Assignee: Magellan Technology Pty Limited
    Inventors: Stuart Colin Littlechild, Michael John Stanton
  • Publication number: 20080169826
    Abstract: A time period of an event is determined by charging a known value capacitor from a constant current source during the event. The resultant voltage on the capacitor is proportional to the event time period and may be calculated from the resultant voltage and known capacitance value. Capacitance is measured by charging a capacitor from a constant current source during a known time period. The resultant voltage on the capacitor is proportional to the capacitance thereof and may be calculated from the resultant voltage and known time period. A long time period event may be measured by charging a first capacitor at the start of the event and a second capacitor at the end of the event, while counting clock times therebetween. Delay of an event is done by charging voltages on first and second capacitors at beginning and end of event, while comparing voltages thereon with a reference voltage.
    Type: Application
    Filed: January 12, 2007
    Publication date: July 17, 2008
    Inventor: James E. Bartling
  • Patent number: 7173882
    Abstract: A simple electronic horological device, termed a time cell, is presented with associated methods, systems, and computer program products. A time cell has an insulated, charge storage element that receives an electrostatic charge through its insulating medium, i.e. it is programmed. Over time, the charge storage element then loses the electrostatic charge through its insulating medium. Given the reduction of the electric potential of the programmed charge storage element at a substantially known discharge rate, and by observing the electric potential of the programmed charge storage element at a given point in time, an elapsed time period can be determined. Thus, the time cell is able to measure an elapsed time period without a continuous power source.
    Type: Grant
    Filed: February 15, 2005
    Date of Patent: February 6, 2007
    Assignee: International Business Machines Corporation
    Inventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
  • Patent number: 7021068
    Abstract: Methods and apparatus for monitoring power outages in a household appliance such as a refrigerator are disclosed. According to the method, a household appliance determines a prior occurrence of a power outage to the appliance. The household appliance then computes a duration of the power outage. Further, the household appliance alerts a user of the duration of the power outage.
    Type: Grant
    Filed: March 1, 2004
    Date of Patent: April 4, 2006
    Assignee: Maytag Corporation
    Inventors: Nelson J. Ferragut, II, John L. Mc Namara, Louis Montuoro
  • Patent number: 6950375
    Abstract: Multi-phase clock time stamping for improving time stamp resolution is provided. One of many possible embodiments is a method for generating a time stamp having an improved time resolution for an event signal. Briefly described, one such method comprises the steps of: receiving an event signal for which a time stamp is to be generated; generating a first pulse signal having a pulse width defined by the event signal and a first clock signal; generating a second pulse signal having a pulse width defined by the event signal and a second clock signal; and determining which of the first pulse signal and the second pulse signal is to be used for generating the time stamp for the event signal.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: September 27, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: Barbara J. Duffner, Larry S Metz
  • Patent number: 6931338
    Abstract: A system for calibrating cables attached to a time measurement device is disclosed. The system includes a calibration device that generates a plurality of synchronized measurement signals that are communicated to a time measurement device by a set of cables. The calibration device can also generate at least one arming signal that is also communicated to the time measurement device. By determining the relative arrival time of a common reference event of each of the measurement signals, the time measurement device can determine any skew that exists between each of the cables that input the measurement signals. The skew can then be used to compensate for varying cable skew in future time measurements. In one embodiment, the system of the present invention can also be used to determine the arming latency of the time measurement device by delaying the measurement signals in relation to the arming signals and observing the delay time which causes complete synchronization of the measurement signals.
    Type: Grant
    Filed: January 7, 2003
    Date of Patent: August 16, 2005
    Assignee: Guide Technology, Inc.
    Inventor: Shalom Kattan
  • Patent number: 6909672
    Abstract: A time interval to voltage converter with very low nonlinearity for time stamping events. The converter automatically selects one of two clocks related to a reference clock and ensures that the time between an event edge to a clock edge is sufficiently large to properly operate a switch and yield very linear time-to-voltage conversion.
    Type: Grant
    Filed: September 24, 2002
    Date of Patent: June 21, 2005
    Assignee: General Electric Company
    Inventor: Naresh Kesavan Rao
  • Patent number: 6856581
    Abstract: A simple electronic horological device, termed a time cell, is presented with associated methods, systems, and computer program products. A time cell has an insulated, charge storage element that receives an electrostatic charge through its insulating medium, i.e. it is programmed. Over time, the charge storage element then loses the charge through its insulating medium. Given the reduction of the electric potential of the programmed charge storage element at a substantially known discharge rate, and by observing the potential of the programmed charge storage element at a given point in time, an elapsed time period can be determined. Thus, the time cell measures an elapsed time period without a continuous power source. One type of time cell is an analog time cell that may have a form similar to a non-volatile memory cell, particularly a floating gate field effect transistor (FGFET). The time cell may have an expanded floating gate for storing an electrostatic charge.
    Type: Grant
    Filed: October 31, 2000
    Date of Patent: February 15, 2005
    Assignee: International Business Machines Corporation
    Inventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
  • Patent number: 6831879
    Abstract: A simple electronic horological device, termed a time cell, is presented with associated methods, systems, and computer program products. A time cell has an insulated, charge storage element that receives an electrostatic charge through its insulating medium, i.e. it is programmed. Over time, the charge storage element then loses the charge through its insulating medium. Given the reduction of the electric potential of the programmed charge storage element at a substantially known discharge rate, and by observing the potential of the programmed charge storage element at a given point in time, an elapsed time period can be determined. Thus, the time cell measures an elapsed time period without a continuous power source. One type of time cell is an analog time cell that may have a form similar to a non-volatile memory cell, particularly a floating gate field effect transistor (FGFET). The time cell may have an expanded floating gate for storing an electrostatic charge.
    Type: Grant
    Filed: October 31, 2000
    Date of Patent: December 14, 2004
    Assignee: International Business Machines Corporation
    Inventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
  • Patent number: 6829200
    Abstract: A simple electronic horological device, termed a time cell, is presented with associated methods, systems, and computer program products. A time cell has an insulated, charge storage element that receives an electrostatic charge through its insulating medium, i.e. it is programmed. Over time, the charge storage element then loses the electrostatic charge through its insulating medium. Given the reduction of the electric potential of the programmed charge storage element at a substantially known discharge rate, and by observing the electric potential of the programmed charge storage element at a given point in time, an elapsed time period can be determined. Thus, the time cell is able to measure an elapsed time period without a continuous power source. One type of time cell is a binary time cell that may have a form similar to a non-volatile memory cell.
    Type: Grant
    Filed: October 31, 2000
    Date of Patent: December 7, 2004
    Assignee: International Business Machines Corporation
    Inventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
  • Patent number: 6826128
    Abstract: A simple electronic horological device, termed a time cell, is presented with associated methods, systems, and computer program products. A time cell has an insulated, charge storage element that receives an electrostatic charge through its insulating medium, i.e. it is programmed. Over time, the charge storage element then loses the charge through its insulating medium. Given the reduction of the electric potential of the programmed charge storage element at a substantially known discharge rate, and by observing the potential of the programmed charge storage element at a given point in time, an elapsed time period can be determined. Thus, the time cell measures an elapsed time period without a continuous power source. One type of time cell is an analog time cell that may have a form similar to a non-volatile memory cell, particularly a floating gate field effect transistor (FGFET). The time cell may have an expanded floating gate for storing an electrostatic charge.
    Type: Grant
    Filed: October 31, 2000
    Date of Patent: November 30, 2004
    Assignee: International Business Machines Corporation
    Inventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
  • Patent number: 6711908
    Abstract: Methods and apparatus for monitoring power outages in a household appliance such as a refrigerator are disclosed. According to the method, a household appliance determines a prior occurrence of a power outage to the appliance. The household appliance then computes a duration of the power outage. Further, the household appliance alerts a user of the duration of the power outage.
    Type: Grant
    Filed: July 15, 2002
    Date of Patent: March 30, 2004
    Assignee: Maytag Corporation
    Inventors: Nelson J. Ferragut, II, John L. McNamara, Louis Montuoro
  • Patent number: 6701280
    Abstract: Improved input circuitry for use in conjunction with measurement devices is disclosed. The subject input circuitry enables a single measurement device to take measurements on both single-ended and differential signal inputs. Software-implemented control signals can be programmed by a user or set to default values to select which type of input signal is to be measured. The input circuitry minimizes the use of electromechanical relays and other components or phenomena that may degrade the quality of the input signals, and also includes resistor networks to additionally help maintain signal integrity. A plurality of common programmable voltage sources is provided for use in accordance with select embodiments of the disclosed technology to serve as either termination voltages, threshold voltages, or both.
    Type: Grant
    Filed: March 22, 2002
    Date of Patent: March 2, 2004
    Assignee: Guide Technology
    Inventors: Steven Horne, Shalom Kattan
  • Patent number: 6657706
    Abstract: A method and apparatus for resolving relative times-of-arrival of a plurality of light pulses includes a plurality of drift-field detectors. Each drift-field detector includes a light sensor and a semiconductor drift region. Each light sensor generates an electrical charge from at least one of the plurality of light pulses. Each semiconductor drift region receives the electrical charge from its respective light sensor and, pursuant to an electric field therein, produces a spatial charge distribution. The spatial charge distribution for each of the semiconductor drift regions is stored in an analog storage device associated therewith. The relative positions of the charge distributions in the semiconductor drift regions are used to calculate the relative times-of-arrival of the light pulses.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: December 2, 2003
    Assignee: Sarnoff Corporation
    Inventors: Peter Alan Levine, Taner Dosluoglu, Nathaniel Joseph McCaffrey, John Robertson Tower
  • Patent number: 6621767
    Abstract: A time interval analyzer for measuring time intervals between events in an input signal includes a trigger circuit that receives the input signal and that outputs a time trigger signal at a first triggering level upon occurrence of a first input signal event. A time counter receives a time base signal and increments a time count at each period of the time base signal. The time count is calibrated to a predetermined reference time. A processor circuit is in communication with the trigger circuit and the time counter so;that the processor circuit receives the time trigger signal and reads the time count from the time counter. The processor circuit is configured to read the time count upon receiving the time trigger signal at the first triggering level so that the time count read by the processor circuit indicates the time at which the first input signal event occurred with respect to the predetermined reference time.
    Type: Grant
    Filed: July 14, 1999
    Date of Patent: September 16, 2003
    Assignee: Guide Technology, Inc.
    Inventor: Shalom Kattan
  • Patent number: 6574168
    Abstract: A time measuring device includes: an input signal detecting unit for detecting three or more edges in an input signal and to output three or more detection signals in parallel, the three or more detection signals changing based on the three or more edges, respectively; a converting unit for converting phase differences between change timings of the detection signals and clock edges in a reference clock having a predetermined operating frequency into analog voltage values, respectively; a counting unit for counting, from change timings of at least two of the detection signals, number of the clock edges between the clock edges from which at least two detection signals are respectively delayed by the phase differences corresponding to at least two detection signals; an operating unit for calculating a time interval between edges of the three or more edges based on the analog voltage values and the number of clock edges.
    Type: Grant
    Filed: September 5, 2001
    Date of Patent: June 3, 2003
    Assignee: Advantest Corporation
    Inventor: Mishio Hayashi
  • Patent number: 6498770
    Abstract: A timer circuit that utilizes the thermal runaway effect, and includes a switch, a resistor, a transistor and a protective device. The temperature of the transistor rises due to a phenomenon known as the thermal runaway effect, which causes the temperature of the transistor to rise while increasing current flow. This will eventually cause the protective device to activate. The time it takes to activate the protective device is predictable for a given transistor, therefore the circuit operates as a timer. In an alternate embodiment, a heat source is used. This heat source rises in temperature as current flows in the circuit. A heat sensor located near the heat source rises in temperature along with the heat source. A comparator compares the temperature from this heat sensor with the temperature of a heat sensor located further from the heat source. When there is a user-definable difference in temperature due to thermal diffusion between the two heat sensors, power to the transistor is disconnected.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: December 24, 2002
    Assignee: The United States of America as represented by the National Security Agency
    Inventors: Craig A. Rockenbauch, James F. Korenz
  • Publication number: 20020041538
    Abstract: A time measuring device includes: an input signal detecting unit for detecting three or more edges in an input signal and to output three or more detection signals in parallel, the three or more detection signals changing based on the three or more edges, respectively; a converting unit for converting phase differences between change timings of the detection signals and clock edges in a reference clock having a predetermined operating frequency into analog voltage values, respectively; a counting unit for counting, from change timings of at least two of the detection signals, number of the clock edges between the clock edges from which at least two detection signals are respectively delayed by the phase differences corresponding to at least two detection signals; an operating unit for calculating a time interval between edges of the three or more edges based on the analog voltage values and the number of clock edges.
    Type: Application
    Filed: September 5, 2001
    Publication date: April 11, 2002
    Inventor: Mishio Hayashi
  • Patent number: 6364503
    Abstract: A illuminated memorial assembly for providing a substantially continual illumination at a memorial site. The illuminated memorial assembly includes a housing. The housing has a bottom portion and a top portion. A plurality of connecting rods connects the top portion to the bottom portion in a spaced relationship. Each of the rods is elongate and has a first end and a second end. Each of the first ends is coupled to the top portion, and each of the second ends is removably coupled to the bottom portion. A light assembly includes a light bulb. The light bulb is mounted in a light socket, which is mounted on a top surface of the bottom portion. A power source comprises a battery. The battery is mounted in the bottom portion and is operationally coupled to the light socket.
    Type: Grant
    Filed: July 7, 2000
    Date of Patent: April 2, 2002
    Inventors: Herman J. Wenzel, Christina A. Wenzel
  • Patent number: 6181649
    Abstract: A time interval analyzer for measuring time intervals between events in an input signal includes a trigger circuit that receives an input signal and that outputs a trigger signal at a triggering level upon occurrence of a first event and at a non-triggering level upon occurrence of a reference event that follows the first event. A first current circuit has a current source or a current sink. A second current circuit has a current sink or a current source. A capacitor and a shunt are operatively disposed in parallel with respect to the first current circuit. The shunt is disposed between the first current circuit and the second current circuit. The shunt receives the trigger signal and is selectable between conducting and non-conducting states so that the shunt is driven to the conducting state upon receiving the trigger signal at the triggering level and is driven to the non-conducting state upon receiving the trigger signal at a non-triggering level.
    Type: Grant
    Filed: July 14, 1999
    Date of Patent: January 30, 2001
    Assignee: Guide Technology, Inc.
    Inventor: Shalom Kattan
  • Patent number: 6091671
    Abstract: A time interval analyzer for measuring time intervals between events in an input signal includes a trigger circuit that receives an input signal and that outputs a trigger signal at a triggering level upon occurrence of the event. A first current circuit has a constant current source or a constant current sink. A second current circuit has (1) a current sink where the first current circuit has a constant current source or (2) a current source where the first current circuit has a constant current sink. A capacitor and a shunt are operatively disposed in parallel with respect to the first current circuit. The shunt is disposed between the first current circuit and the second current circuit.
    Type: Grant
    Filed: July 14, 1999
    Date of Patent: July 18, 2000
    Assignee: Guide Technology, Inc.
    Inventor: Shalom Kattan
  • Patent number: 5901114
    Abstract: A circuit for measuring the duration of a cut-off period in the power supply to an electronic system, for example the control system of a motor vehicle starter, comprises a voltage splitting bridge and a processing unit receiving the output of the splitting bridge. The bridge supply voltage is derived from the power supply to the electronic system, and the bridge has a branch which includes a temperature variable resistor. The processing unit determines the duration of the cut-off period as a function of the value of the output voltage from the splitting bridge at the end of a cut-off period.
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: May 4, 1999
    Assignee: Valeo Electronique
    Inventors: Philippe Baravian, Alfred Permuy
  • Patent number: 5870352
    Abstract: Methods and circuits to measure the speed of silicon test structures using direct current test equipment. Each test structure comprises an oscillator and a detector. Oscillations started by a direct current input signal are rectified by the detector into a direct current output signal. Start of oscillations cause a jump in the output signal and that point is correlated with the input signal strength which in turn is correlated to the speed of the test circuits. By knowing the speed of the test circuits the quality of the manufacturing process can be checked. Direct current greatly simplifies measurement so that 100% testing can be performed.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: February 9, 1999
    Assignee: Tritech Microelectric International, Ltd.
    Inventors: Esa Tarvainen, Hannu Roukainen
  • Patent number: 5790480
    Abstract: A method and apparatus for measuring very short time periods, or differences between two events, such as the delta-T between a trigger point on a waveform and a sampling clock edge of a digital oscilloscope. The delta-T measurements are made using the time-to-voltage transformation of an integrator. The output sweep ramp of the integrator is normalized to a fixed differential time and differential amplitude by correction current provided by a reference circuit that has a reference integrator substantially identical to the delta-T integrator. The reference integrator is operated at the same timing as the delta-T integrator, and an error correction loop furnishes the right amount of current to both integrators to normalize the peak voltage of both to a predetermined reference voltage.
    Type: Grant
    Filed: May 12, 1997
    Date of Patent: August 4, 1998
    Assignee: Fluke Corporation
    Inventor: Paul Klatser
  • Patent number: 5500834
    Abstract: While the electric power source is turned on, capacitor 1 is charged to a voltage EO by a direct current constant voltage supplier through transistor 4. When the electric power is disconnected, transistor 4 is switched off to discharge capacitor 1 through resistor R1. When the power source is turned on, the voltage of capacitor 1 is read by A/D converter to be produced and stored in CPU 12 memory. Then transistor 4 is switched on to charge capacitor 1 to the voltage EO. Then transistor 4 is switched off and transistor 5 is switched on to discharge capacitor 1 through resistor R2 and a counter stars. When the voltage of capacitor 1 reduces to the same voltage stored in the memory, transistor 5 is switched off to stop the counter and to obtain the counted value t2. Then transistor 4 is switched on to prepare for the next operation. The time lapse t1 after the power source being turned off is obtained by a formula (R1/R2).times.t2.
    Type: Grant
    Filed: August 29, 1994
    Date of Patent: March 19, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Eihiro Sakaki, Yoshimi Ogasawara, Eiichiro Teshima
  • Patent number: 5122996
    Abstract: A method and apparatus performs time-interval to voltage conversion immediately and continuously allowing timing variations to be viewed and correlated with other voltage signals displayed on an oscilloscope. A calibration output assists in calibrating the vertical gain and offset of the oscilloscope. An automatic setup software routine finds suitable resolution and offset settings. The method includes the steps of selecting the type of time-interval to be measured, scaling the counting of a clock signal appropriately, offsetting the counting means as desired, counting the number of clock signals that occur during every selected time-interval, limiting the counted results to a preselected range, and converting the counted results to an analog voltage for display by an oscilloscope.
    Type: Grant
    Filed: August 9, 1990
    Date of Patent: June 16, 1992
    Assignee: Tektronix, Inc.
    Inventors: Stanley K. Sasaki, Clark P. Foley, Michael A. Gauland
  • Patent number: 4982350
    Abstract: An integrated system for precise measurement of time intervals wherein a high resolution and accuracy can be achieved through the implementation of an interpolation function and a self calibration function. The interpolation function scales down a relatively coarse major time base to a finer time base for the portions near the boundaries of the time interval that is being measured. The calibration function is built into the system for facilitating calibration of the interpolation function under actual operating of the system.
    Type: Grant
    Filed: June 10, 1987
    Date of Patent: January 1, 1991
    Assignee: Odetics, Inc.
    Inventors: Nicholas A. Perna, Norman C. Walker
  • Patent number: 4879647
    Abstract: A watchdog timer circuit employed in a microcomputer is disclosed. The watchdog timer circuit detects the occurrence of a program abnormal termination or an infinite loop operation and includes a capacitor, a charging circuit charging the capacitor when a predetermined instruction is executed, a discharging circuit discharging the capacitor when other instructions are executed, a detection circuit detecting the voltage across the capacitor and producing a detection signal when the voltage across the capacitor becomes smaller than a reference voltage, and a reset circuit resets the microcomputer to its initial state in response to an abnormal detection circuit. When the program termination or an infinite loop operation occurs, the predetermined instruction is not executed for a long period of time. The capacitor continues to be discharged. As a result, the detection signal is produced. The microcomputer is thereby reset to its initial state.
    Type: Grant
    Filed: June 11, 1986
    Date of Patent: November 7, 1989
    Assignee: NEC Corporation
    Inventor: Akira Yazawa
  • Patent number: 4870629
    Abstract: A method of calibration for a voltage to time converter in order to increment delays by a fraction of a clock cycle known as an interpolator period is disclosed. The method of calibration compares differences in measurements of a constant and repetitive input waveform while changing current, base voltage threshold, incremental voltage threshold, or any combination thereof to minimize the calibration error for a predetermined number of interpolator periods designed to equal an integral number of clock cycles.
    Type: Grant
    Filed: January 30, 1987
    Date of Patent: September 26, 1989
    Assignee: Hewlett-Packard Company
    Inventors: Ronald L. Swerlein, David A. Czenkusch
  • Patent number: 4769798
    Abstract: An apparatus which successively converts the period defined by successive two pulses of a series of input pulses into a voltage, and in which fractional times between input pulses and clock pulses are converted, by two fractional time-to-voltage converters alternately with each other, into voltage signals and the voltage signals thus alternately yielded by the two converters are alternately applied, by a change-over switch, to a subtractor, wherein a later one of the two successive voltage signals is always subtracted from the earlier one of them, creating a difference signal therebetween. At the same time, the number of clock pulses present between the two input pulses corresponding to the two voltage signals is counted and the count value is converted to analog form, which is added to the difference signal, obtaining the voltage corresponding to the period between the two input pulses.
    Type: Grant
    Filed: February 1, 1988
    Date of Patent: September 6, 1988
    Assignee: Advantest Corporation
    Inventor: Mishio Hayashi
  • Patent number: 4504155
    Abstract: A constant current source is provided to charge a reference capacitor. The current is switched to the capacitor by a first high-speed analog switch when a first event occurs and the current is turned off by a second high-speed analog switch when a second event occurs. The voltage produced by the charge on the capacitor is proportional to the time between events. A sample and hold circuit maintains the maximum voltage on the capacitor when the events are periodic.
    Type: Grant
    Filed: March 1, 1984
    Date of Patent: March 12, 1985
    Assignee: Chip Supply
    Inventor: Joseph A. Ruggieri
  • Patent number: 4394090
    Abstract: An indicating electronic timer useful for timing processing events and for controlling a process measures the elapsed time from a moment at which a process variable attains a predetermined value and produces a signal which varies in accordance with the elapsed time. During a timing operation, the signal is displayed on a display device which normally displays the process variable, and may be such that the display device indicates the percentage of a predetermined time interval which has elapsed. The timer may be conveniently implemented with relatively inexpensive integrated circuits, such as a variable oscillator, binary counters, and D/A converters.
    Type: Grant
    Filed: April 6, 1981
    Date of Patent: July 19, 1983
    Assignee: TRW Inc.
    Inventor: Robert L. Hyde
  • Patent number: 4367957
    Abstract: A time-lapse indicator in which a receptacle contains a fluid material having numerous discrete particles dispersed in a liquid carrier, and a layer of absorbent material in close proximity to the receptacle, the receptacle and absorbent material being separated from one another by a wall which is broken when the time period is to be determined by the indicator. The indicator normally has a pair of electrodes for measuring the resistance of the fluid material after a portion of the liquid carrier has been absorbed therefrom in the absorbent material. Mechanisms for both activating and reading the indicator may be used.
    Type: Grant
    Filed: December 6, 1979
    Date of Patent: January 11, 1983
    Assignee: Micro-Circuits Company
    Inventor: Robert F. Bradley
  • Patent number: 4301360
    Abstract: A time interval meter for measuring extremely short time intervals includes a timing circuit operable at a fast predetermined rate over the time interval between first and second events, and operable at a slow predetermined rate which is precisely scaled to the first rate over a time interval between the occurrence of the second event and the upper limit of a predetermined timing window. During the slow ramp period, clock pulses are counted to provide a count which is proportional to that portion of the predetermined timing window occupied by the slow ramp interval. The fast ramp time interval may then be readily attained by subtracting the slow ramp interval from the total time of the timing window. The circuit includes a control circuit, a timing circuit including a capacitor and a pair of selectable constant current sources, and a counter.
    Type: Grant
    Filed: October 25, 1979
    Date of Patent: November 17, 1981
    Assignee: Tektronix, Inc.
    Inventor: Bruce W. Blair
  • Patent number: 4277745
    Abstract: A low frequency electric field exposure monitor integrates personal exposure to an electric field into intervals of electric field intensity.
    Type: Grant
    Filed: April 12, 1979
    Date of Patent: July 7, 1981
    Assignee: Electric Power Research Institute, Inc.
    Inventor: Don W. Deno
  • Patent number: 4234845
    Abstract: Both positive and negative time interval measurements between start and stop channel signals are made without ambiguity during repetitive measurements. Circuitry monitors the start and stop channel signals and automatically changes the arming of the measurement circuitry whenever drifting of the signals requires a change in arming. Once the start or stop channel event is chosen as the initial source of the arming signal, subsequent arming signal selections are accomplished automatically.
    Type: Grant
    Filed: November 13, 1978
    Date of Patent: November 18, 1980
    Assignee: Hewlett-Packard Company
    Inventor: Mark S. Allen