Including Time Indicating Means Actuated By Voltage Or Electrical Charge Patents (Class 368/121)
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Patent number: 10943876Abstract: 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: GrantFiled: July 24, 2019Date of Patent: March 9, 2021Assignee: STMicroelectronics (Rousset) SASInventors: Fabrice Marinet, Pascal Fornara
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Patent number: 10089164Abstract: 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: GrantFiled: February 25, 2016Date of Patent: October 2, 2018Assignee: MICROCHIP TECHNOLOGY INCORPORATEDInventor: Keith Curtis
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Patent number: 8458705Abstract: 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: GrantFiled: December 17, 2007Date of Patent: June 4, 2013Assignee: Samsung Electronics Co., Ltd.Inventors: Hae-Young Jun, Ji-Eun Keum, Wuk Kim
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Patent number: 7414517Abstract: 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: GrantFiled: June 26, 2007Date of Patent: August 19, 2008Assignee: Magellan Technology Pty LimitedInventors: Stuart Colin Littlechild, Michael John Stanton
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Publication number: 20080169826Abstract: 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: ApplicationFiled: January 12, 2007Publication date: July 17, 2008Inventor: James E. Bartling
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Patent number: 7173882Abstract: 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: GrantFiled: February 15, 2005Date of Patent: February 6, 2007Assignee: International Business Machines CorporationInventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
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Patent number: 7021068Abstract: 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: GrantFiled: March 1, 2004Date of Patent: April 4, 2006Assignee: Maytag CorporationInventors: Nelson J. Ferragut, II, John L. Mc Namara, Louis Montuoro
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Patent number: 6950375Abstract: 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: GrantFiled: December 17, 2002Date of Patent: September 27, 2005Assignee: Agilent Technologies, Inc.Inventors: Barbara J. Duffner, Larry S Metz
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Patent number: 6931338Abstract: 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: GrantFiled: January 7, 2003Date of Patent: August 16, 2005Assignee: Guide Technology, Inc.Inventor: Shalom Kattan
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Patent number: 6909672Abstract: 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: GrantFiled: September 24, 2002Date of Patent: June 21, 2005Assignee: General Electric CompanyInventor: Naresh Kesavan Rao
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Patent number: 6856581Abstract: 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: GrantFiled: October 31, 2000Date of Patent: February 15, 2005Assignee: International Business Machines CorporationInventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
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Patent number: 6831879Abstract: 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: GrantFiled: October 31, 2000Date of Patent: December 14, 2004Assignee: International Business Machines CorporationInventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
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Patent number: 6829200Abstract: 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: GrantFiled: October 31, 2000Date of Patent: December 7, 2004Assignee: International Business Machines CorporationInventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
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Patent number: 6826128Abstract: 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: GrantFiled: October 31, 2000Date of Patent: November 30, 2004Assignee: International Business Machines CorporationInventors: Viktors Berstis, Peter Juergen Klim, Chung Lam
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Patent number: 6711908Abstract: 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: GrantFiled: July 15, 2002Date of Patent: March 30, 2004Assignee: Maytag CorporationInventors: Nelson J. Ferragut, II, John L. McNamara, Louis Montuoro
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Patent number: 6701280Abstract: 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: GrantFiled: March 22, 2002Date of Patent: March 2, 2004Assignee: Guide TechnologyInventors: Steven Horne, Shalom Kattan
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Patent number: 6657706Abstract: 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: GrantFiled: March 27, 2002Date of Patent: December 2, 2003Assignee: Sarnoff CorporationInventors: Peter Alan Levine, Taner Dosluoglu, Nathaniel Joseph McCaffrey, John Robertson Tower
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Patent number: 6621767Abstract: 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: GrantFiled: July 14, 1999Date of Patent: September 16, 2003Assignee: Guide Technology, Inc.Inventor: Shalom Kattan
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Patent number: 6574168Abstract: 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: GrantFiled: September 5, 2001Date of Patent: June 3, 2003Assignee: Advantest CorporationInventor: Mishio Hayashi
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Patent number: 6498770Abstract: 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: GrantFiled: September 28, 2000Date of Patent: December 24, 2002Assignee: The United States of America as represented by the National Security AgencyInventors: Craig A. Rockenbauch, James F. Korenz
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Publication number: 20020041538Abstract: 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: ApplicationFiled: September 5, 2001Publication date: April 11, 2002Inventor: Mishio Hayashi
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Patent number: 6364503Abstract: 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: GrantFiled: July 7, 2000Date of Patent: April 2, 2002Inventors: Herman J. Wenzel, Christina A. Wenzel
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Patent number: 6181649Abstract: 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: GrantFiled: July 14, 1999Date of Patent: January 30, 2001Assignee: Guide Technology, Inc.Inventor: Shalom Kattan
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Patent number: 6091671Abstract: 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: GrantFiled: July 14, 1999Date of Patent: July 18, 2000Assignee: Guide Technology, Inc.Inventor: Shalom Kattan
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Patent number: 5901114Abstract: 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: GrantFiled: July 16, 1997Date of Patent: May 4, 1999Assignee: Valeo ElectroniqueInventors: Philippe Baravian, Alfred Permuy
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Patent number: 5870352Abstract: 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: GrantFiled: July 11, 1997Date of Patent: February 9, 1999Assignee: Tritech Microelectric International, Ltd.Inventors: Esa Tarvainen, Hannu Roukainen
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Patent number: 5790480Abstract: 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: GrantFiled: May 12, 1997Date of Patent: August 4, 1998Assignee: Fluke CorporationInventor: Paul Klatser
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Patent number: 5500834Abstract: 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: GrantFiled: August 29, 1994Date of Patent: March 19, 1996Assignee: Canon Kabushiki KaishaInventors: Eihiro Sakaki, Yoshimi Ogasawara, Eiichiro Teshima
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Patent number: 5122996Abstract: 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: GrantFiled: August 9, 1990Date of Patent: June 16, 1992Assignee: Tektronix, Inc.Inventors: Stanley K. Sasaki, Clark P. Foley, Michael A. Gauland
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Patent number: 4982350Abstract: 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: GrantFiled: June 10, 1987Date of Patent: January 1, 1991Assignee: Odetics, Inc.Inventors: Nicholas A. Perna, Norman C. Walker
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Patent number: 4879647Abstract: 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: GrantFiled: June 11, 1986Date of Patent: November 7, 1989Assignee: NEC CorporationInventor: Akira Yazawa
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Patent number: 4870629Abstract: 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: GrantFiled: January 30, 1987Date of Patent: September 26, 1989Assignee: Hewlett-Packard CompanyInventors: Ronald L. Swerlein, David A. Czenkusch
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Patent number: 4769798Abstract: 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: GrantFiled: February 1, 1988Date of Patent: September 6, 1988Assignee: Advantest CorporationInventor: Mishio Hayashi
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Patent number: 4504155Abstract: 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: GrantFiled: March 1, 1984Date of Patent: March 12, 1985Assignee: Chip SupplyInventor: Joseph A. Ruggieri
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Patent number: 4394090Abstract: 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: GrantFiled: April 6, 1981Date of Patent: July 19, 1983Assignee: TRW Inc.Inventor: Robert L. Hyde
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Patent number: 4367957Abstract: 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: GrantFiled: December 6, 1979Date of Patent: January 11, 1983Assignee: Micro-Circuits CompanyInventor: Robert F. Bradley
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Patent number: 4301360Abstract: 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: GrantFiled: October 25, 1979Date of Patent: November 17, 1981Assignee: Tektronix, Inc.Inventor: Bruce W. Blair
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Patent number: 4277745Abstract: A low frequency electric field exposure monitor integrates personal exposure to an electric field into intervals of electric field intensity.Type: GrantFiled: April 12, 1979Date of Patent: July 7, 1981Assignee: Electric Power Research Institute, Inc.Inventor: Don W. Deno
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Patent number: 4234845Abstract: 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: GrantFiled: November 13, 1978Date of Patent: November 18, 1980Assignee: Hewlett-Packard CompanyInventor: Mark S. Allen