Frequency Detection Patents (Class 327/47)
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Patent number: 7952344Abstract: A frequency characteristic measuring apparatus measures a device under test in which the frequency of an input signal and the frequency of an output signal differ from each other, simplifying the configuration of a tracking generator and peripheral circuits associated with the tracking generator, and simultaneously measuring the characteristics of the input signal and the output signal of the device under test. A spectrum analyzer has mixers, local oscillators and IF sections as first and second measuring units for measuring frequency characteristics of two input signals by performing frequency sweep in correspondence with a first or second frequency range, a mixer and an oscillator as a tracking generator section which operates by being linked to the frequency sweep operation in the first measuring unit, and a section which generates a trigger signal designating measurement start timing.Type: GrantFiled: February 2, 2009Date of Patent: May 31, 2011Assignee: Advantest CorporationInventors: Wataru Doi, Yohei Hirakoso
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Patent number: 7932751Abstract: A circuit is described that detects high and low frequencies and additional clock frequencies and outputs a signal that indicates a high, a low frequency or an additional mode. When in the low frequency low frequency mode signals are regenerated free of any high frequency signals from appearing on the filtered low frequency clock line. The rising and falling edges of the input clock are low pass filtered separately and then combined to generate a low frequency clock or the additional input clock and that retains the input clock pulse width and duty cycle.Type: GrantFiled: February 5, 2009Date of Patent: April 26, 2011Assignee: Fairchild Semiconductor CorporationInventor: James B. Boomer
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Patent number: 7873139Abstract: A signal processing device includes a detecting part that detects intensity of an input signal, a timer part that includes a time constant circuit and measures time based on a time constant of the time constant circuit, and a determination circuit that counts the number of times of switching of the input signal detected by the detecting part within the time measured by the time constant circuit.Type: GrantFiled: March 30, 2009Date of Patent: January 18, 2011Assignees: NEC Corporation, Renesas Electronics CorporationInventors: Noriaki Matsuno, Yoshinori Horiguchi, Yuu Yamaguchi, Orie Tsuzuki, Tomonobu Kurihara, Isao Sakakida, Tadashi Maeda, Tomoyuki Yamase
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Patent number: 7855581Abstract: Method for monitoring a real time clock and a device having real time clock monitoring capabilities, the device includes: (i) a real time clock tree, (ii) a clock frequency monitor that is adapted to determine a frequency of a real time clock signal, during a short monitoring period; (iii) a monitoring enable module, adapted to activate the clock frequency monitor during short motoring periods and to deactivate the clock frequency monitor during other periods, wherein the monitoring enable module is adapted to determine a timing of the short monitoring periods in a non-deterministic manner; and (iv) a real time clock violation indication generator adapted to indicate that a real time clock violation occurred, in response to an error signal provided from the clock frequency monitor.Type: GrantFiled: August 8, 2006Date of Patent: December 21, 2010Assignee: Freescale Semiconductor, Inc.Inventors: Michael Priel, Asaf Ashkenazi, Dan Kuzmin
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Patent number: 7847597Abstract: A frequency change detector splits a frequency standard signal into two undelayed frequency signals, one of which is delayed by a predetermined amount. The delayed signal is then mixed with the undelayed frequency signal into a mixed signal that is further filtered and amplified for providing an output signal indicating frequency changes of the frequency standard signal. The mixed frequency signal indicates frequency changes of the original frequency standard signal without reference to another frequency standard. This frequency change detector is well suited for use on satellites as an early warning detection of changes in on-board atomic frequency standards.Type: GrantFiled: June 15, 2009Date of Patent: December 7, 2010Assignee: The Aerospace CorporationInventors: Yat C. Chan, James C. Camparo, Walter A. Johnson, Christine Humphries, legal representative, Albert M. Young, Sarunas K. Karuza
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Patent number: 7821302Abstract: A method and system for monitoring a frequency of a clock signal is disclosed. The method and system comprise dividing a clock signal into a plurality of clock signal components. The method and system further comprise adding a delay to each of the clock signal components and comparing the plurality of signal components with each of the delayed clock signal components to monitor whether the clock signal is within a predetermined frequency range. The method and system includes providing an output signal indicative of a condition of the clock signal based upon the comparing step.Type: GrantFiled: May 24, 2007Date of Patent: October 26, 2010Assignee: Atmel Rousset S.A.S.Inventor: Jean-Francois Guiramand
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Publication number: 20100231265Abstract: A method of detecting a minimum operational frequency includes: generating a signal that becomes an oscillating signal at a first predetermined frequency; and generating a logic signal to provide a level transition when a frequency of the oscillating signal reaches a second predetermined frequency corresponding to the minimum operational frequency. The logic signal is generated by: providing a transistor that is activated at the second predetermined frequency; providing a capacitor; storing charges in the capacitor when the oscillating signal is below the second predetermined frequency; discharging the capacitor when the transistor is activated by the oscillating signal; and outputting the logic signal when the capacitor discharges.Type: ApplicationFiled: May 21, 2010Publication date: September 16, 2010Inventors: Ryan Andrew Jurasek, Bret Roberts Dale, Darin James Daudelin, Dave Eugene Chapmen
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Publication number: 20100225357Abstract: Method for monitoring a real time clock and a device having real time clock monitoring capabilities, the device includes: (i) a real time clock tree, (ii) a clock frequency monitor that is adapted to determine a frequency of a real time clock signal, during a short monitoring period; (iii) a monitoring enable module, adapted to activate the clock frequency monitor during short motoring periods and to deactivate the clock frequency monitor during other periods, wherein the monitoring enable module is adapted to determine a timing of the short monitoring periods in a non-deterministic manner; and (iv) a real time clock violation indication generator adapted to indicate that a real time clock violation occurred, in response to an error signal provided from the clock frequency monitor.Type: ApplicationFiled: August 8, 2006Publication date: September 9, 2010Applicant: Freescale Semiconductor, Inc.Inventors: Michael Priel, Asaf Ashkenazi, Dan Kuzmin
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Patent number: 7786763Abstract: A clock circuit includes a phase-lock loop for generating an output clock signal based on a data signal and a harmonic frequency detector for detecting whether the frequency of the output clock signal is a harmonic frequency of a frequency of a reference clock signal. The harmonic frequency detector includes a counter for generating a first divided clock signal by dividing the frequency of the output clock signal by a first divisor. Additionally, the harmonic frequency detector includes a counter for generating a second divided clock signal by dividing the frequency of the reference clock signal by a second divisor. The harmonic frequency detector also includes a frequency comparator for generating an output indicating whether the frequency of the output clock signal is a harmonic frequency of the frequency of the reference clock signal based on the first divided clock signal and the second divided clock signal.Type: GrantFiled: December 30, 2008Date of Patent: August 31, 2010Assignee: Integrated Device Technology, Inc.Inventors: Jagdeep Bal, Tao Jing
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Patent number: 7785284Abstract: The joint (36) comprises a tubular body (37) having two connecting zones (38, 39) each connected by an end to a tubular element (40) of a fluid transport line, giving continuity to passage of fluid. The tubular body is made of a mixture of an electrically-conductive material such as PVC, with carbon black to give it electrical conductivity. The joint has an internal surface (41) which is destined to come into contact with the transported fluid, and an external surface which is destined to have a grounded galvanic contact. The joint is inserted in the discharge fluid drainage line of a dialyzer filter, in an apparatus for intensive treatment of acute renal insufficiency, for eliminating ECG artefacts due to functioning of peristaltic pumps in the apparatus.Type: GrantFiled: September 7, 2007Date of Patent: August 31, 2010Assignee: Gambro Lundia ABInventors: Vincenzo Baraldi, Annalisa Delnevo, Gianfranco Marchesi, Andrea Ligabue, Massimo Zaccarelli
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Patent number: 7764088Abstract: A frequency detection circuit and a detection method thereof suitable for a clock data recovery (CDR) circuit are provided. The frequency detection circuit includes a phase detector, a first delayer, a frequency detector, and a logic circuit. The phase detector samples a data signal according to a first clock signal provided by the CDR circuit and provides a phase instruction signal according to the sampling. The first delayer delays the first clock signal to obtain a second clock signal. The frequency detector samples the data signal according to the second clock signal and provides a frequency instruction signal according to the sampling. The logic circuit generates a clock instruction signal according to the phase instruction signal and the frequency instruction signal. The CDR circuit adjusts the frequency of the first clock signal according to the status of the clock instruction signal.Type: GrantFiled: September 24, 2008Date of Patent: July 27, 2010Assignee: Faraday Technology Corp.Inventors: Kuan-Yu Chen, Wen-Ching Hsiung, Cheng-Tao Chang, Chia-Liang Lai
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Patent number: 7750685Abstract: A first embodiment of the present invention relates to a frequency and phase locked loop (FPLL) synthesizer having a frequency-locked loop (FLL) operating mode and a phase-locked loop (PLL) operating mode. The FLL operating mode is used for rapid coarse tuning of the FPLL synthesizer and is followed by the PLL operating mode for fine tuning and stabilization of the frequency of an output signal from the FPLL synthesizer. A second embodiment of the present invention relates to a high resolution frequency measurement circuit that is capable of directly measuring the frequency of a high frequency signal to provide a high resolution frequency measurement using a lower frequency reference signal, and may include linear feedback shift register (LFSR) circuitry and LFSR-to-binary conversion circuitry. A third embodiment of the present invention relates to an FPLL having an FLL that includes the high resolution frequency measurement circuit.Type: GrantFiled: October 15, 2008Date of Patent: July 6, 2010Assignee: RF Micro Devices, Inc.Inventors: Ryan Bunch, Stephen T. Janesch
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Patent number: 7750684Abstract: A power-on detection circuit for detecting a minimum operational frequency includes: an oscillating circuit, which includes: a ring oscillator, for generating a first oscillating signal; and a high pass filter for filtering the first oscillating signal to generate a second oscillating signal. The power-on detection circuit also includes a rectification device, coupled to the high pass filter, for generating a logic signal once the second oscillating signal reaches a certain frequency.Type: GrantFiled: April 18, 2008Date of Patent: July 6, 2010Assignee: Nanya Technology Corp.Inventors: Ryan Andrew Jurasek, Bret Roberts Dale, Darin James Daudelin, Dave Eugene Chapmen
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Patent number: 7737730Abstract: An integrated circuit includes a first switched capacitor element and a second switched capacitor element, which are coupled to form a bridge circuit, the first switched capacitor element being located in a first branch of the bridge circuit and the second switched capacitor element being located in a second branch of the bridge circuit. A detector circuit is coupled to the first branch and to the second branch of the bridge circuit. Switching signals of the first switched capacitor element and of the second switched capacitor element are generated on the basis of an input clock signal of the integrated circuit.Type: GrantFiled: August 31, 2007Date of Patent: June 15, 2010Assignee: Infineon Technologies AGInventors: Mikael Hjelm, Charlotta Hedenaes, Bjoern Wiklund
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Patent number: 7710161Abstract: A digital circuit is disclosed for detecting clock activity in an integrated circuit (IC) device. In one implementation, a clock detection circuit can include two flip flops. A first flip flop detects activity on the clock being tested (e.g., the flip flop is set when a positive clock edge is detected). A second flip flop is coupled to the output of first flip flop and is operable by an enable signal to sample the output of the first flip flop. The output of the second flip flop is asserted as active, when a positive clock edge occurs between the release of the reset signal on the first flip flop and the assertion of the enable signal on the second flip flop. In some implementations, one or more additional flips can be interposed between the first and second flips to control metastability.Type: GrantFiled: January 13, 2009Date of Patent: May 4, 2010Assignee: ATMEL CorporationInventor: Colin Bates
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Patent number: 7696789Abstract: Disclosed is a high-frequency signal detector circuit including a diode detector circuit for detecting an input signal by diode detection; a differential-input/differential output amplifier with a common mode feedback circuit, the amplifier including a differential amplifying circuit for differentially receiving outputs of the diode detector circuit and outputting a differential output signal, and a common mode feedback circuit for controlling the differential amplifying circuit in such a manner that a voltage corresponding to a mid-point of the differential output signal from the differential amplifying circuit will take on a voltage identical with a prescribed voltage; and a differential-input/single-ended output amplifier for receiving the differential output signal of the differential amplifying circuit and outputting a single-ended output signal.Type: GrantFiled: May 23, 2008Date of Patent: April 13, 2010Assignee: NEC Electronics CorporationInventor: Naohiro Matsui
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Publication number: 20100052732Abstract: In some preferred embodiments, a switched capacitor circuit configured to change its equivalent resistance depending on the frequency of an input clock signal and a resistor element are connected in series. A power source voltage is divided by the equivalent resistance of the switched capacitor circuit and the resistance of the resistor element, and the divided voltage is inputted to a Schmitt circuit. The Schmitt circuit outputs a high-level signal when the inputted divided voltage is higher than a threshold voltage and a low-level signal when the inputted divided voltage is lower than a threshold voltage. Thus, depending on the frequency of the input clock signal, a high-level signal or a low-level signal is outputted.Type: ApplicationFiled: July 24, 2009Publication date: March 4, 2010Inventor: Takashi TOKANO
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Publication number: 20090310730Abstract: A frequency detector includes an error measurement unit measuring a time interval between zero-crossing points of an input signal that is modulated. An error conversion unit quantizes the measured time interval using one of modulation time intervals. An error calculation unit calculates a frequency error based upon a difference between the measured time interval and the quantized time interval. An error generation control unit controls whether to output the frequency error based upon the quantized time interval, the calculated frequency error, and a predetermined critical value.Type: ApplicationFiled: April 27, 2009Publication date: December 17, 2009Inventors: Sergey Zhidkov, Jun Ho Huh, Ki Seop Kwon
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Patent number: 7626436Abstract: An Automatic System Clock Detection System (ASCDS) may provide integrated circuits (ICs) with the capability to detect the frequency of an external crystal oscillator or clock source, and adjust the IC's internal PLL accordingly for proper IC operation. The frequency detection and PLL adjustment may be performed without any additional pins on the IC, and/or without requiring any additional external information. The ASCDS may be configured with an internal ring oscillator, which may be generated from standard logic elements, a watchdog counter, and an input clock counter. When the IC comes out of power on reset (POR), the ASCDS may compare the input clock counter with the watchdog counter, and determine the clock frequency of the input clock. It may then set the PLL parameters to ensure correct IC operation.Type: GrantFiled: November 14, 2007Date of Patent: December 1, 2009Assignee: Standard Microsystems CorporationInventors: Shawn Shaojie Li, Akhlesh Nigam, Mark R. Bohm, Michael J. Pennell
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Patent number: 7616034Abstract: Disclosed is a data output control circuit for controlling data output. The data output control circuit includes a delay lock loop for outputting a first clock by delaying an external clock in response to a control signal, a phase detector for outputting a detection signal by detecting a frequency of the external clock in response to the control signal, a decoder for outputting a selection signal by decoding the detection signal, and a delay unit for outputting a second clock by delaying the first clock or inverting and delaying a phase of the first clock in response to the selection signal.Type: GrantFiled: June 29, 2007Date of Patent: November 10, 2009Assignee: Hynix Semiconductor Inc.Inventor: Hyeng Ouk Lee
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Patent number: 7600140Abstract: A logic circuit system with power consumption that is reduced by automatically varying the clock frequency and operating voltage according to processing capability imposed on programmable logic circuits. The programmable logic circuits are capable of achieving plural circuit functions dynamically and can change realized circuit functions during operation. In addition, the system has a voltage supply portion for supplying a voltage to the programmable logic circuits, a clock signal supply portion for supplying a clock signal to the programmable logic circuits, a change control portion for changing the circuit functions realized by the programmable logic circuits to any one of the circuit functions, an operation time measuring portion for measuring the operation times of the programmable logic circuits to perform processing to achieve the circuit functions, respectively, and a clock-and-voltage determination portion for determining the frequency of the clock signal and the voltage, using the operation times.Type: GrantFiled: July 16, 2007Date of Patent: October 6, 2009Assignee: Kabushiki Kaisha ToshibaInventors: Taku Ohneda, Shinichi Kanno, Masaya Tarui, Yukimasa Miyamoto
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Publication number: 20090140774Abstract: A system and method are provided for communicating data among chained circuits. In operation, a period of a signal communicated between a chain of circuits is identified. Additionally, a state of the signal is determined, based on the period of the signal.Type: ApplicationFiled: December 3, 2007Publication date: June 4, 2009Inventors: Jeff Kotowski, Shane Hollmer
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Patent number: 7504865Abstract: A frequency sensor includes at least one a resistor element and a capacitor. A frequency is detected according to a charging/discharging time to/from the capacitor, thereby realizing a frequency sensor with reduced power consumption and reduced circuit scale. Further, plural resistors and plural capacitors can be provided, along with switches connected to the respective resistors and capacitors. Additionally, a time constant can be adjusted after production, whereby variations in production can be reduced. Furthermore, a self-diagnosis circuit can be included for determining whether the frequency sensor itself operates normally or not. Thus, a highly-reliable frequency sensor can be realized.Type: GrantFiled: December 6, 2004Date of Patent: March 17, 2009Assignee: Panasonic CorporationInventors: Rie Itoh, Eiichi Sadayuki
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Publication number: 20090058468Abstract: An integrated circuit includes a first switched capacitor element and a second switched capacitor element, which are coupled to form a bridge circuit, the first switched capacitor element being located in a first branch of the bridge circuit and the second switched capacitor element being located in a second branch of the bridge circuit. A detector circuit is coupled to the first branch and to the second branch of the bridge circuit. Switching signals of the first switched capacitor element and of the second switched capacitor element are generated on the basis of an input clock signal of the integrated circuit.Type: ApplicationFiled: August 31, 2007Publication date: March 5, 2009Inventors: Mikael Hjelm, Charlotta Hedenaes, Bjoern Wiklund
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Patent number: 7499044Abstract: An image display system synchronizes the display of images on a plurality of display devices. The system includes a first computer system generating a first signal representing first image data to be displayed on a first display device, a second computer system generating a second signal representing second image data to be displayed on a second display device, and means for synchronizing the first and second image data. The synchronizing means includes a phase-locked loop circuit having a digital rate controller. The digital rate controller allows programmable control of the speed of the phase-locked loop.Type: GrantFiled: October 30, 2003Date of Patent: March 3, 2009Assignee: Silicon Graphics, Inc.Inventors: Joseph P Kennedy, John A Klenoski, Greg Sadowski
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Patent number: 7471117Abstract: The circuit for detecting the maximal frequency of the pulse frequency modulation includes an oscillator-controlling unit, a delay circuit and a master-slave register. The oscillator-controlling unit is connected to an oscillator, which generates the pulse frequency modulation signals, and includes a first-half pulse-generating module and a second-half pulse-generating module. The delay circuit is connected to the second-half pulse-generating module. The master-slave register includes a clock, an input end and an output end, wherein the input end is connected to the oscillator-controlling unit, and the clock is connected to the delay circuit.Type: GrantFiled: March 20, 2007Date of Patent: December 30, 2008Assignee: Advanced Analog Technology, Inc.Inventors: Li Chieh Chen, Yu Min Sun, Chu Yu Chu
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Patent number: 7454645Abstract: A circuit and method are provided herein for monitoring the status of a clock signal. In general, the method may include supplying a pair of clock signals to a clock monitor circuit, which is configured for monitoring a status of one clock signal relative to the other. The status indicates whether the frequency of the one clock signal is faster, slower or substantially equal to the frequency of the other clock signal. Once determined, the status may be stored as a bit pattern within a status register, which is operatively coupled to the clock monitor circuit. This enables the status to be read by detecting a logic state of one or more bits within the status register.Type: GrantFiled: March 31, 2005Date of Patent: November 18, 2008Assignee: Cypress Semiconductor Corp.Inventors: Gabriel M. Li, Greg J. Richmond, Sangeeta Raman
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Patent number: 7427879Abstract: The present invention discloses a frequency detecting apparatus for detecting a frequency of an input clock. The frequency detecting apparatus includes: a pulse generator, a digital signal generator, and a decoder. The pulse generator is coupled to the input clock for extracting a period of the input clock to generate a pulse, and the digital signal generator is coupled to the pulse generator for converting the pulse into a plurality of logic values. The digital signal generator includes: a delay module coupled to the pulse, for delaying the pulse to generate a plurality of delayed pulses according to a plurality of delay amounts, respectively; and a sampling module coupled to the delay module for sampling the pulse to generate the logic values according to the delayed pulses, respectively. The decoder is coupled to the digital signal generator for determining the frequency of the input clock according to the logic values.Type: GrantFiled: November 22, 2006Date of Patent: September 23, 2008Assignee: Nanya Technology Corp.Inventor: Wen-Chang Cheng
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Publication number: 20080205498Abstract: A method is provided for edge formation of signals and transmitter/receiver component for a bus system. A transmitter/receiver component for a bus system comprises a driver transistor, which is to be looped between a bus line of the bus system and a reference potential and is used to output signals on the bus line, a control unit for the driver transistor, a high-frequency interference detector, which is configured in such a way that it detects a high-frequency interference level on the bus line of the bus system, whereby the control unit is configured in such a way that it controls the driver transistor, depending on the detected high-frequency interference level, in such a way that an edge steepness of the output signals increases when the high-frequency interference level on the bus line increases, and an edge steepness of the output signals decreases when the high-frequency interference level on the bus line decreases.Type: ApplicationFiled: December 4, 2007Publication date: August 28, 2008Inventors: Fred Liebermann, Axel Pannwitz
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Publication number: 20080197885Abstract: The circuit for detecting the maximal frequency of the pulse frequency modulation includes an oscillator-controlling unit, a delay circuit and a master-slave register. The oscillator-controlling unit is connected to an oscillator, which generates the pulse frequency modulation signals, and includes a first-half pulse-generating module and a second-half pulse-generating module. The delay circuit is connected to the second-half pulse-generating module. The master-slave register includes a clock, an input end and an output end, wherein the input end is connected to the oscillator-controlling unit, and the clock is connected to the delay circuit.Type: ApplicationFiled: March 20, 2007Publication date: August 21, 2008Applicant: ADVANCED ANALOG TECHNOLOGY, INC.Inventors: Li Chieh Chen, Yu Min Sun, Chu Yu Chu
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Patent number: 7401306Abstract: A verification support apparatus verifies an object. The object includes a plurality of clock domains and each clock domain includes a plurality of registers. The verification support apparatus includes an input receiving unit that receives logical circuit description information on the object; a specifying unit that specifies at least two registers in one clock domain that output data to an adjacent clock domain; and a detecting unit that detects, based on the logical circuit description information and specified registers, a re-convergence register in the adjacent clock domain that achieves convergence.Type: GrantFiled: October 20, 2005Date of Patent: July 15, 2008Assignee: Fujitsu LimitedInventor: Satoshi Kowatari
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Patent number: 7356106Abstract: A clock and data recovery (CDR) circuit comprises a phase detector (PD) and a quadrature phase (QP) detector. A frequency detector (FD) is coupled to the PD and QP detector. The FD detects frequency difference between the output signals of the PD and QP detector and provides an FD output signal. A summer is coupled to the PD and FD for summing the PD and FD output signals, and for providing a summer output signal. The CDR further comprises a voltage-controlled oscillator (VCO) for receiving a direct current signal and providing a recovered clock signal. A polyphase filter is coupled to each of the VCO, PD, and QP detector. A re-timer is coupled to the polyphase filter and provides a re-timed data signal, wherein the CDR circuit is on-chip and the polyphase filter converts clock signals into phase reference signals.Type: GrantFiled: September 7, 2004Date of Patent: April 8, 2008Assignee: Agency for Science, Technology and ResearchInventors: Aruna B. Ajjikuttira, Nuntha Kumar s/o Krishnasamy Maniam
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Patent number: 7343512Abstract: Systems and methods for controlling clock rates of circuits are provided. The systems and methods, collectively referred to as clock rate control, generate a clock rate control parameter from data of one or more fuses. The clock rate control detects any overclocked signal of received clock signals by determining a clock signal is running faster than a threshold represented by the clock rate control parameter. The clock rate control controls a circuit clock rate using a selected signal of the clock signals that is not an overclocked signal.Type: GrantFiled: November 14, 2005Date of Patent: March 11, 2008Assignee: ATI Technologies, Inc.Inventor: Andrew S. Brown
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Patent number: 7292070Abstract: A device such as a programmable logic device (“PLD”) includes circuitry for detecting the PPM frequency difference between two input clock signals. For example, this circuitry may accept a user-programmable PPM threshold value and output a signal when this threshold value is met.Type: GrantFiled: August 9, 2005Date of Patent: November 6, 2007Assignee: Altera CorporationInventors: Seungmyon Park, Ramanand Venkata, Chong Lee
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Patent number: 7259595Abstract: A frequency detection circuit and method of detecting the frequency of a clock signal, and a latency signal generation circuit for a semiconductor memory device that includes the frequency detection circuit. The frequency detection circuit includes a frequency detector and an output controller, which determines whether or not the frequency of the clock signal is higher than a predetermined value. Embodiments of the invention have an increased accuracy, increased efficiency, and a reduced current consumption over conventional art.Type: GrantFiled: May 2, 2005Date of Patent: August 21, 2007Assignee: Samsung Electronics Co., Ltd.Inventor: Myeong-O Kim
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Patent number: 7242223Abstract: A frequency monitor circuit (FMC) that is part of an integrated circuit chip for monitoring the frequency of one or more clocks present on the chip is disclosed. The FMC includes a reference window generator, operative to output a reference window signal of a given duration, and a clock counter, operative to count all pulses, in any one of the clocks, that occur within the duration of the reference window and to output a corresponding pulse count. The FMC further includes two or more comparators, each operative to compare the pulse count with a respective given threshold value and to output a corresponding indication of frequency deviation. In one configuration, in which the clock is generated on the chip by a frequency multiplier, the reference window generator and the clock counter are shared between the frequency monitor circuit and the frequency multiplier.Type: GrantFiled: March 10, 2004Date of Patent: July 10, 2007Assignee: National Semiconductor CorporationInventor: Moshe Alon
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Patent number: 7224751Abstract: A device and method are disclosed, whereby the normally complicated and difficult frequency determination is achieved by simply arranged and executed measures, namely by means of larger, smaller and/or equal comparisons and a counting of certain events. The invention further relates to arrangements whereby the noise signal level, or the influence thereof on the verification to be carried out is reduced.Type: GrantFiled: May 23, 2001Date of Patent: May 29, 2007Assignee: Infineon Technologies AGInventors: Alessandro Fulli, Peter Pessl, Christian Schranz, Michael Staber
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Patent number: 7216279Abstract: An integrated circuit, where a hard macro is resident within the integrated circuit. The hard macro receives a clock signal at a frequency that is below the operational frequency of the integrated circuit, and produces a clock signal having a frequency that is at least equal to the operational frequency of the integrated circuit. The hard macro has a first input that receives a first signal from the tester. A second input receives a second signal from the tester, offset by substantially ninety degrees from the phase of the first signal. A speed select input receives a signal, where the signal is selectively set at one of a logical high indicating a first multiplier to be applied in the hard macro, and a logical low indicating a second multiplier to be applied in the hard macro. A clock multiplication circuit receives the first signal, selectively receives the second signal, and receives the speed select signal, and produces the clock signal.Type: GrantFiled: July 19, 2005Date of Patent: May 8, 2007Assignee: LSI Logic CorporationInventors: Kevin J. Gearhardt, Anita M. Ekren
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Patent number: 7215163Abstract: A device and method is described for the frequency division of an input clock signal, in which from the input clock signal at least two output clock signals are generated, with an output pulse frequency equal to an input pulse frequency divided by a given factor, whereby with a phase detector a phase difference is measured between the at least two output signals and each of the at least two output clock signals is either inverted or not inverted, as a function of the phase difference determined. A method of this type is particularly suitable for the demultiplexing of an input data signal, and can also be designed to be multi-step.Type: GrantFiled: September 29, 2004Date of Patent: May 8, 2007Assignee: Infineon Technologies AGInventors: Dirk Scheideler, Philipp Börker
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Patent number: 7183810Abstract: A circuit for detecting phase includes a first inverter, a second inverter, a differential amplifier, an output load latch and an output latch. The first and second inverters receive an input signal and an inverted input signal to generate first and second differential input signals in response to a clock signal and first and second control signals, respectively, and shut off transmissions of the input signal and the inverted input signal. The differential amplifier differentially amplifies the first and second differential input signals in response to the clock signal to provide first and second differential output signals as the first and second control signals. The output load latch latches the first and second differential output signals to generate the first and second latch output signals. The output latch latches the first and second latch output signals to output a phase detection signal.Type: GrantFiled: July 25, 2005Date of Patent: February 27, 2007Assignee: Samsung Electronics Co., Ltd.Inventor: Kwang-Il Park
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Patent number: 7171323Abstract: An integrated circuit is provided comprising a processor, an onboard system clock having a ring oscillator for generating a clock signal, a memory, and clock trim circuitry. The processor is arranged to, in response to receiving an external signal, determine the number of cycles of the clock signal during a predetermined number of cycles of the external signal or the number of cycles of the external signal during a predetermined number of cycles of the clock signal and to output the determined number of cycles to an external circuit. The processor is also arranged to, in response to receiving a trim value based on the determined number of cycles from the external circuit, store the trim value in the memory and control the clock trim circuitry to trim the frequency of the clock signal generated by the ring oscillator using the trim value.Type: GrantFiled: August 29, 2005Date of Patent: January 30, 2007Assignee: Silverbrook Research Pty LtdInventors: Gary Shipton, Simon Robert Walmsley
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Patent number: 7154305Abstract: Systems and methods for monitoring frequencies of periodic electrical signals are disclosed. According to one technique, a first and second counters are respectively clocked by a first periodic electrical signal to be monitored and a second periodic electrical, and a threshold detector resets one of the counters when a count of the other counter crosses a reset threshold and determines whether a frequency error has occurred based on whether a count of the one of the counters crosses an alarm threshold. Another technique according to an embodiment of the invention also involves clocking counters with respective periodic electrical signals, although error detection is based on whether the counts of the counters cross respective associated thresholds in other than a particular sequence with respect to each other.Type: GrantFiled: December 22, 2004Date of Patent: December 26, 2006Assignee: AlcatelInventors: Steve Driediger, Dion Pike
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Patent number: 7148755Abstract: A system and method that can be utilized to implement voltage adjustment (e.g., for an integrated circuit). In one embodiment, the system comprises a frequency generator that provides a clock signal having a frequency that varies based on an operating voltage. The system also includes a controller that provides a control signal to adjust the operating voltage based on adjustments to the frequency of the clock signal.Type: GrantFiled: August 26, 2003Date of Patent: December 12, 2006Assignee: Hewlett-Packard Development Company, L.P.Inventors: Samuel D. Naffziger, Shahram Ghahremani, Christopher A. Poirier
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Patent number: 7145367Abstract: A phase-locked loop circuit has a fractional-frequency-interval phase frequency detector, a charge pump, an oscillator, and a divider. The fractional-frequency-interval phase frequency detector has a phase frequency detector unit that is utilized as or comprises a plurality of phase frequency detector units. The divider is responsive to the oscillator and provides divider values for dividing an oscillator frequency by the divider values to provide a feedback frequency of a feedback loop signal of the phase-locked loop circuit. A reference input frequency is input as a first input into the phase frequency detector unit. The feedback frequency is input and selectively delayed as second inputs into the phase frequency detector unit so that the second inputs are aligned for input according to the reference input frequency and an oscillator frequency is, in effect, responsive to the phase frequency detector units and allowed to be divided by a fractional-integer divider value.Type: GrantFiled: January 13, 2006Date of Patent: December 5, 2006Assignee: Cirrus Logic, Inc.Inventor: John L. Melanson
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Patent number: 7134042Abstract: A frequency detection circuit according to the present invention has a status holding register for storing rise information and fall information about a check target clock and outputting an error detection signal showing frequency abnormality when information showing the next edge (a fall or a rise) from a rise or a fall of the check target clock is not stored, a rise/fall detection circuit for respectively detecting a rise and a fall of the check target clock and outputting a rise detection signal in response to the rise and a fall detection signal in response to the fall, a sampling clock generation circuit for generating sampling clock for storing the information about the check target clock, and an edge detection signal generation circuit for outputting an edge detection signal which is an edge detection result of the check target clock based on the rise detection signal and the fall detection signal.Type: GrantFiled: December 22, 2003Date of Patent: November 7, 2006Assignee: NEC Electronics CorporationInventor: Shinya Shimasaki
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Patent number: 7096137Abstract: An integrated circuit, comprising a processor, an onboard system clock for generating a clock signal, and clock trim circuitry, the integrated circuit being configured to: (a) receive an external signal; (b) determine either the number of cycles of the clock signal during a predetermined number of cycles of the external signal, or the number of cycles of the external signal during a predetermined number of cycles of the clock signal; (c) store a trim value in the integrated circuit, the trim value having been determined on the basis of the determined number of cycles; and (d) use the trim value to control the internal clock frequency.Type: GrantFiled: December 2, 2003Date of Patent: August 22, 2006Assignee: Silverbrook Research PTY LTDInventors: Gary Shipton, Simon Robert Walmsley
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Patent number: 7061287Abstract: Provided is a delay locked loop comprising: a delay unit for delaying a clock supplied from an external chipset by a predetermined delay amount; a replica for delaying the clock delayed in the delay unit by a delay amount of a clock path and a data path; and a phase detector for generating a signal for controlling the delay amount of the delay unit comparing the clock supplied from the external chipset with a phase of an output of the replica, and generating a reset signal through detection of a change of a clock frequency supplied from the external chipset.Type: GrantFiled: June 30, 2004Date of Patent: June 13, 2006Assignee: Hynix Semiconductor Inc.Inventor: Young Jin Jeon
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Patent number: 7038497Abstract: A fully differential phase and frequency detector utilizes a multi-function differential logic gate to implement a differential AND gate operation and provides a fully differential D-flip-flop. The multi-function differential logic gate has four inputs, which can be grouped into two pairs of true and complement signals. By selectively re-assigning the inputs to different signal pairs, the differential logic gate can be made to provide one of either simultaneous AND/NAND logic operations or simultaneous OR/NOR logic operations. The differential D-flip-flop is implemented following a master/slave configuration and is response to the true and complement forms of an input clock signal, an input reset input, and input data signal, and also provides true and complement forms of an output signal. All components within the phase and frequency detector are exemplified in CML circuit configuration.Type: GrantFiled: April 28, 2004Date of Patent: May 2, 2006Assignee: Seiko Epson CorporationInventors: David Meltzer, Muralikumar A. Padaparambil, Tat C. Wu
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Patent number: 7038496Abstract: The present invention relates to a device for comparison CMP, which is designed to emit a control signal Vcnt, which is representative of a difference which exists between the input signal frequencies Vdiv and Vref. The device according to the invention includes a phase/frequency comparator PD, which supplies a regulation signal Tun, which is subjected to pulse width modulation according to the difference observed. The device also includes a current source, which is designed to emit a charge current Ics, with a value which is controlled by the regulation signal Tun. The device further includes a capacitive element Cs, which is designed to generate the control signal Vcnt, under the effect of the charge current Ics. By means of a regulation signal Tun, which has a frequency which is virtually constant, the invention makes it possible to impose high-frequency variations on the control signal Vcnt.Type: GrantFiled: November 28, 2001Date of Patent: May 2, 2006Assignee: Koninklijke Philips Electronics N.V.Inventors: David Canard, Vincent Fillatre
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Patent number: 6963735Abstract: A method and arrangement for receiving a frequency modulated signal, includes mixing the frequency modulated signal into a low-frequency signal, detecting the falling and rising edges of said low-frequency signal and forming a second signal on the basis of the edge detection, where the frequency of the second signal is twice the frequency of the low-frequency signal, and frequency detecting the second signal to form a demodulated signal.Type: GrantFiled: April 26, 2001Date of Patent: November 8, 2005Assignee: Nokia Mobile Phones Ltd.Inventor: Risto Väisänen