Synchronizing Patents (Class 327/141)
  • Patent number: 7778377
    Abstract: Methods and apparatus are provided for generating a frequency with a predefined offset from a reference frequency. A spread spectrum generator circuit is disclosed that comprises a voltage controlled delay loop for generating a plurality of signals having a different phase; and at least one interpolator for processing at least two of the signals to generate an output signal having a phase between a phase of the at least two of the signals, wherein the output is varied between a phase of the at least two of the signals to generate the spread spectrum. A spread spectrum having a frequency lower than an applied clock signal is generated using a continuous phase delay increase and a spread spectrum having a frequency higher than the clock signal is generated using a continuous phase delay decrease.
    Type: Grant
    Filed: May 31, 2005
    Date of Patent: August 17, 2010
    Assignee: Agere Systems Inc.
    Inventors: Vladimir Sindalovsky, Lane A. Smith, Craig B. Ziemer
  • Patent number: 7777536
    Abstract: A synchronization circuit includes a first flip-flop circuit to hold an input signal which is asynchronous to a clock signal by the clock signal, and output an output signal, a second flip-flop circuit to hold the input signal by a signal of an opposite phase to the clock signal and output a signal, a comparing unit to compare the input signal and the output signal of the first flip-flop circuit and output a signal with a high or low level depending on whether the input signal and the output signal of the first flip-flop circuit have the same level, a selection unit to select one of the output signal of the first flip-flop circuit and the output signal of the second flip-flop circuit depending on the level of the signal outputted by the comparing unit, and a third flip-flop circuit to output the output signal selected by the selection unit.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: August 17, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Tsukasa Yagi
  • Publication number: 20100201405
    Abstract: A drive control circuit generates switching drive signals for a single phase of a multiphase voltage regulator. A driver circuitry generates the switching drive signals for the voltage regulator responsive to a clock signal. A clock circuitry generates the clock signal responsive to a monitored external clock signal. A phase number detector determines a number of active phases in the multiphase voltage regulator in real time responsive to an indicator on a phase number input monitored by the phase detector.
    Type: Application
    Filed: December 31, 2009
    Publication date: August 12, 2010
    Applicant: INTERSIL AMERICAS INC.
    Inventors: FAISAL AHMAD, WEIHONG QIU, NATTORN PONGRATANANUKUL
  • Patent number: 7772910
    Abstract: An internal clock generator, system and method of generating the internal clock are disclosed. The method comprises detecting the level of an operating voltage within the system, comparing the level of the operating voltage to a target voltage level and generating a corresponding detection signal, and selecting between a normal clock and an alternate clock having a period longer than the period of the normal clock in relation to the detection signal and generating an internal clock on the basis of the selection.
    Type: Grant
    Filed: March 10, 2008
    Date of Patent: August 10, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Chul-Ho Lee, Jin-Yub Lee
  • Patent number: 7772905
    Abstract: It is made possible to provide a flip-flop circuit capable of implementing the error correction function with a small area increase as far as possible and a pipeline system using such a flip-flop circuit. A flip-flop circuit includes: a flip-flop configured to operate based on a rising edge or a falling edge of a first clock signal; a decision circuit configured to compare an input of the flip-flop with an output thereof and output a request signal when the input of the flip-flop is different from the output thereof; and a control circuit configured to receive a second clock signal from outside and generate the first clock signal and a confirmation signal. When the request signal is sent from the decision circuit after the flip-flop has been activated, the control circuit inverts the first clock signal, sends the confirmation to the decision circuit, and makes the decision circuit cancel the request signal.
    Type: Grant
    Filed: September 24, 2007
    Date of Patent: August 10, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinichi Yasuda, Keiko Abe
  • Publication number: 20100188122
    Abstract: A method and device are disclosed for synchronizing an inverter with an alternating voltage source. The method includes measuring a current generated by the alternating voltage source and flowing through diodes of the inverter, determining a phase angle and angular velocity relating to the alternating voltage source from the measured current for enabling synchronization between the inverter and the alternating voltage source, and starting modulation of the inverter according to the obtained phase angle and angular velocity.
    Type: Application
    Filed: January 27, 2010
    Publication date: July 29, 2010
    Applicant: ABB OY
    Inventor: Mikko VERTANEN
  • Patent number: 7764755
    Abstract: A method of synchronization of a digital circuit includes selecting a first site and a second site from a plurality of different sites of the digital circuit where a signal to be synchronized occurs; passing a first signal, which is the signal to be synchronized of the first site, via a first line that starts at the first site, ends at the second site, and contacts each of the sites just once, to the second site; passing a second signal, which is the signal to be synchronized of the second site, via a second line that starts at the second site, ends at the first site, and contacts each of the sites just once, to the first site; determining, for each site, a first phase shift between the signal to be synchronized of this site and the first signal, and a second phase shift between the signal to be synchronized of this site and the second signal; and determining, from the first and second phase shifts of each site, a delay for each site, with which the signal to be synchronized of the respective site is delayed
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: July 27, 2010
    Assignee: Qimonda AG
    Inventors: Michael Brünnert, Paul Georg Lindt
  • Publication number: 20100182045
    Abstract: According to one general aspect, an apparatus may include a clock channel, a shielding tunnel, and clock repeaters. In various embodiments, the clock channel may be configured to carry the clock signal, and may include a portion of a metal layer of an integrated circuit. In some embodiments, the shielding tunnel may be configured to shield, in at least four directions, the clock channel from other signals, and may include portions of a at least three metal layers of the integrated circuit. The shielding tunnel may be connected to the positive and negative supplies in order to provide the required power for the clock repeaters.
    Type: Application
    Filed: September 8, 2009
    Publication date: July 22, 2010
    Applicant: Broadcom Corporation
    Inventor: Afshin Momtaz
  • Publication number: 20100166128
    Abstract: A receiver for clock reconstitution in a semiconductor field includes a termination resistor arranged between two input stages, to which a pair of input signals are input, the termination resistor including a first resistor and a second resistor; a strobe signal generator for generating a strobe signal, using a first signal corresponding to a differential voltage output from a node between the first resistor and the second resistor; and a clock reconstitutor for generating a clock signal in response to the strobe signal generated from the strobe signal generator.
    Type: Application
    Filed: December 27, 2009
    Publication date: July 1, 2010
    Inventor: Dae-Joong Jang
  • Publication number: 20100164576
    Abstract: A transit state element circuit. The transit state element circuit includes a clock input stage coupled to receive a clock signal, an output stage configured to drive an output signal on an output node and an activation stage coupled to an input node. The activation stage is configured to, responsive to the clock input stage detecting a transition from a first logic level to a second logic level and detecting a logical transition of an input signal on the input node, activate the output stage to drive an output signal on the output node. A storage element is configured to capture a logic value of the input signal when the clock is at the second logic level and to store the logic value, and to provide the output signal on the output node when the clock signal is at the first logic level.
    Type: Application
    Filed: December 29, 2008
    Publication date: July 1, 2010
    Inventor: Robert P. Masleid
  • Patent number: 7746972
    Abstract: A numerically-controlled phase-lock loop with input clock dependent ratio adjustment provides for narrower-bandwidth loops that lock to a wide range of frequencies and/or operation with an absent or degraded input timing reference. A timing reference characteristic detector determines an input frequency range of the input timing reference signal, the data type of the timing reference, and/or whether a timing reference signal of sufficient quality is present. A numerically controlled oscillator is controlled by a numeric ratio that is adjusted to provide the desired clock frequency output in conformity with the detected frequency range and/or data type. If the timing reference signal is absent or degraded, then the numeric ratio can be set to a fixed value or a local timing reference can be applied in order to generate the desired clock output frequency.
    Type: Grant
    Filed: March 22, 2007
    Date of Patent: June 29, 2010
    Assignee: Cirrus Logic, Inc.
    Inventors: John L. Melanson, Zhong You, Scott Allan Woodford, Steven Randall Green
  • Patent number: 7746142
    Abstract: Circuit and methods for automatic clock skew compensation in circuits having two power domains. When one of the power domains is operated with a lowered supply voltage, lowering the supply voltage tends to slow the clock pulse and produces clock skew. Circuitry is provided for selectively delaying the clock pulse in one of the power domains to reduce the clock skew by comparing the clock pulses, and then automatically delaying the clock pulse in one of the domains by a delay determined to minimize the skew. A method is provided where the clock skew between two clock pulses is determined and the delay needed in one of the clock pulses to reduce the skew is determined by sampling the clock skew using a plurality of delays at multiples of a minimum delay, and then automatically delaying the one clock pulse by selecting an appropriate delay. The method may be iterated.
    Type: Grant
    Filed: October 13, 2008
    Date of Patent: June 29, 2010
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Wei-Pin Changchein, Shu Yi Ying, Fu-Lung Hsueh
  • Publication number: 20100148833
    Abstract: The domain crossing circuit of a semiconductor memory apparatus for improving a timing margin includes a sampler that provides a sampling internal signal generated by delaying an internal input signal by a predetermined time in response to a clock and an edge information signal that defines an output timing of the sampling internal signal and an output stage that allows the sampling internal signal to be synchronized with the clock in response to the edge information signal to be output as a final output signal.
    Type: Application
    Filed: June 17, 2009
    Publication date: June 17, 2010
    Inventors: Hae Rang CHOI, Yong Ju KIM, Sung Woo HAN, Hee Woong SONG, Ic Su OH, Hyung Soo KIM, Tae Jin HWANG, Ji Wang LEE, Jae Min JANG, Chang Kun PARK
  • Patent number: 7738617
    Abstract: Techniques and apparatus for a clock and data recovery circuit to lock to data having frequency offsets relative to a local clock reference are disclosed. One embodiment includes a multi-step frequency tracking system in which each step is used to track a sub-range of frequency deviation from local clock reference. The frequency tracking sub-range of each step is selected so that the clock and data recovery system is relatively assured of achieving lock when the frequency of the incoming data lies within or is relatively near the frequency tracking sub-range of the selected step. Embodiments may use control signals to select the sub-ranges, and hence guide the frequency tracking portion of the clock and data recovery circuit to operate in a frequency tracking range that is optimized for achieving and maintaining lock.
    Type: Grant
    Filed: September 28, 2005
    Date of Patent: June 15, 2010
    Assignee: PMC-Sierra, Inc.
    Inventors: Guillaume Fortin, Larrie Carr, Yuiry Greshishchev, Alex Cochran, Junqi (Paul) Hua
  • Patent number: 7737740
    Abstract: An integrated circuit including a first circuit block having a power supply terminal for receiving a first power supply voltage and an output terminal for providing a first data signal is provided. The integrated circuit further includes a second circuit block having a power supply voltage terminal for receiving a second power supply voltage and an input terminal coupled to the output terminal of the first circuit block for receiving the first data signal. The integrated circuit further includes a first programmable delay block for adding a first delay time to the first data signal when one or both of the first or second power supply voltages is changed.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: June 15, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Brian M. Millar, Andrew P. Hoover
  • Publication number: 20100141308
    Abstract: A method for the recovery of a clock signal from a data signal is provided where the edges of the signals are each represented as a chronologically-ordered sequence of timing points. In one procedural stage, a plurality of timing points of the data signal are processed in parallel as follows: resolving the timing points of the data signal by a nominal clock pulse; estimating the bit-period deviations for the adjusted timing points; and injecting the nominal clock pulse to the estimated bit-period deviations.
    Type: Application
    Filed: August 20, 2008
    Publication date: June 10, 2010
    Applicant: ROHDE & SCHWARZ GMBH & CO. KG
    Inventors: Rubén Villarino-Villa, Markus Freidhof, Thomas Kuhwald
  • Patent number: 7733129
    Abstract: A memory clock signal is generated in response to a reference clock signal and a clock enable signal. The memory clock signal with a frequency identical to that of the reference clock signal is generated during the clock enable signal is in an enabled state; and the memory clock signal with a reduced frequency is generated when the clock enable signal is changed from the enabled state to a disabled state. The generation of a memory clock signal is adaptive so as to save power.
    Type: Grant
    Filed: July 3, 2008
    Date of Patent: June 8, 2010
    Assignee: Via Technologies, Inc.
    Inventor: Chi Chang
  • Patent number: 7735038
    Abstract: A design structure to reduce power consumption within a clock gated synchronous circuit, said synchronous circuit comprising at least two successive stages, wherein each stage if activated propagates a data signal cycle by cycle to a succeeding stage the two successive stages comprising at least a control register, a data register and a local clock buffer (LCB) each, wherein each stage if activated propagates a data signal stored within the data register cycle by cycle to a data register of a succeeding stage.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: June 8, 2010
    Assignee: International Business Machines Corporation
    Inventors: Tobias Gemmeke, Jens Leenstra, Jochen Preiss
  • Patent number: 7729460
    Abstract: A method and a device of providing timing information within a wireless communication system is described. The timing information is extracted from a received transmit signal. The inventive method comprises the steps of providing a training signal on the receiver side relating to a known signal portion of the transmit signal, scaling the training signal, quantizing the scaled training signal, correlating one or more parts of the received transmit signal with the scaled training signal to obtain one or more correlation results, and determining the timing information on the basis of the correlation results.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: June 1, 2010
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Fabian Wenger, Uwe Dettmar, Udo Wachsmann, Peter Schramm
  • Patent number: 7729459
    Abstract: A system and method is disclosed for providing a robust ultra low power serial interface with a digital clock and data recovery circuit for power management systems. In one advantageous embodiment a digital clock and data recovery circuit of the invention comprises a quadruple phase clock generator circuit that generates four shifted clock signals, a decision logic circuit, a state detector circuit, and an edge detector circuit. The detected edges of data signals are used to latch the state of the four shifted clock signals. The state detector circuit selects a stable clock signal among the four shifted clock signals for use as a recovered clock signal and synchronizes the recovered clock signal at a center of the data signal. The selected recovered clock signal remains available until another data signal transition is detected.
    Type: Grant
    Filed: March 31, 2005
    Date of Patent: June 1, 2010
    Assignee: National Semiconductor Corporation
    Inventors: Dae Woon Kang, James T. Doyle
  • Patent number: 7725754
    Abstract: A dual clock interface for an integrated circuit is described. An integrated circuit includes interface circuitry. The interface circuitry has a hardwired logic block. The hardwired logic block has a clock divider circuit coupled to receive a user clock signal and a core clock signal for dividing the core clock signal responsive to a frequency of the user clock signal to provide a divided clock signal with edges aligned to the core clock signal. The divided clock signal has the frequency of the user clock signal and a phase relationship of the user clock signal. User-side logic is coupled to receive the divided clock signal for the controlled passing of information responsive to the divided clock signal. Core-side logic is coupled to receive the core clock signal for the controlled passing of information responsive to the core clock signal.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: May 25, 2010
    Assignee: Xilinx, Inc.
    Inventor: Laurent Fabris Stadler
  • Patent number: 7724862
    Abstract: The phase locked loop (PLL) with adjustable phase shift is described. The PLL includes a voltage controlled oscillator which is capable of generating multiple phase shifted output signals, and multiple phase detectors capable of determining the phase differences between the output signals and a reference clock. The PLL further includes a weighting device capable of weighting the phase differences and generating a control signal for the voltage controlled oscillator.
    Type: Grant
    Filed: June 17, 2008
    Date of Patent: May 25, 2010
    Assignee: International Business Machines Corporation
    Inventors: Christian Ivo Menolfi, Thomas Helmut Toifl
  • Publication number: 20100123525
    Abstract: Implementations of varactor systems compare current data with immediately prior data to determine whether there has been a change in the data, and enable a clock signal for data paths which have changed data.
    Type: Application
    Filed: November 17, 2008
    Publication date: May 20, 2010
    Applicant: Infineon Technologies AG
    Inventor: Andreas Roithmeier
  • Publication number: 20100123496
    Abstract: A multi-branch frequency translation system converts a plurality of independent input clocks to a common frequency. One of the converted clock signals is selected as a dominant clock. The remaining converted clock signals are edge-synchronized with the dominant clock. When the system selects another converted clock signal for use as the dominant clock, the newly selected signal already is edge-synchronized with the dominant clock and, therefore, switchover losses can be avoided. The dominant clock can be subject of further frequency translation processes and output from the system.
    Type: Application
    Filed: February 13, 2009
    Publication date: May 20, 2010
    Applicant: Analog Devices, Inc.
    Inventors: Wyn Terence PALMER, Kenny GENTILE
  • Patent number: 7721137
    Abstract: A bus receiver receives at least one first signal and a second signal both generated from a chip connected to a parallel bus. The bus receiver includes a receiving module and a deskewing module. The receiving module is electrically connected to the parallel bus and receives the first signal and the second signal transmitted through the parallel bus. The deskewing module is electrically connected to the receiving module and deskews the phase of the first signal and the phase of the second signal. The first signal and the second signal are in the same phase.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: May 18, 2010
    Assignee: Via Technologies, Inc.
    Inventors: Ming-Te Lin, Chi Chang
  • Publication number: 20100117691
    Abstract: A system and method for synchronizing otherwise independent oscillators private to I2C Bus slave devices. An I2C Bus master device is capable of issuing two new general call commands, MEASURE PULSE and RESET PRESCALE. The I2C Bus slave devices respond to the MEASURE PULSE command by returning a digital count related to the number of ticks its local, private oscillator cycles through during a signal pulse on the I2C Bus. All such I2C Bus slave devices measure the same signal pulse on the I2C Bus, so the differences in the digital measurements returned during the MEASURE PULSE command are proportional to their respective oscillator frequencies. The various digital measurements returned are used to calculate appropriate oscillator prescale factors that will harmonize the final product frequencies of all of the local oscillators on all of the I2C Bus slave devices in the system.
    Type: Application
    Filed: November 11, 2008
    Publication date: May 13, 2010
    Applicant: NXP B.V.
    Inventors: Jay Richard Lory, Alma Stephenson Anderson
  • Publication number: 20100103748
    Abstract: A clock path control circuit includes a clock control signal generating unit configured to generate a clock control signal having an activation period corresponding to an activation period of a data input buffer; and a clock transfer unit configured to provide a clock signal to a write clock path in response to the clock control signal during the activation period of the clock control signal.
    Type: Application
    Filed: December 30, 2008
    Publication date: April 29, 2010
    Inventor: Jae-Il KIM
  • Patent number: 7706413
    Abstract: A synchronization system (D) for equipment of a synchronous transport network comprises, firstly, a first synchronization module (MA) comprising i) a first submodule (SM1A) delivering a first intermediate clock signal derived from a first external reference clock signal or an internal reference clock signal, ii) a second submodule (SM2A) delivering a first main reference clock signal derived from the first intermediate clock signal or a second intermediate clock signal, and iii) a third submodule (SM3A) delivering a first output reference clock signal derived from the first main reference clock signal or a second main reference clock signal, and, secondly, a second synchronization module (MB) comprising i) a first submodule (SM1B) delivering the second intermediate clock signal derived from another first external reference clock signal and another internal reference clock signal, ii) a second submodule (SM2B) delivering the second main reference clock signal derived from the first or the second intermediate c
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: April 27, 2010
    Assignee: Alcatel
    Inventors: Philippe Dollo, Yannick Stephan, Benoit Morin
  • Publication number: 20100097107
    Abstract: One embodiment of the present invention provides a system that augments a circuit design with a mechanism for detecting and correcting timing errors. This system first partitions the circuit into a set of blocks that are clocked by an independent clock source, and integrates an error signal propagation circuit between the set of blocks. For a respective block, the system determines a set of internal registers that are to be implemented as double data sampling registers, and replaces the determined set of internal registers with double data sampling registers, wherein a given double data sampling register is configured to generate an error signal when it detects a timing error. Then, the system integrates a two-phase error correction circuit into the respective block, wherein when notified of a timing error by a double data sampling register, the two-phase error correction circuit is configured to stall registers in the respective block.
    Type: Application
    Filed: October 22, 2008
    Publication date: April 22, 2010
    Applicant: SYNOPSYS, INC.
    Inventors: Florentin Dartu, Narendra V. Shenoy
  • Publication number: 20100097108
    Abstract: A semiconductor device having a nonvolatile variable resistor, includes: a resistance value conversion circuit unit configured to convert a resistance value of the nonvolatile variable resistor into a potential or a current and which outputs the converted potential or current; a comparison circuit unit configured to compare the output from the resistance value conversion circuit unit and a potential or current at a node of a portion within the semiconductor device; and a resistance value changing circuit unit configured to change the resistance value of the nonvolatile variable resistor based on the comparison results from the comparison circuit unit.
    Type: Application
    Filed: January 18, 2008
    Publication date: April 22, 2010
    Inventors: Tadahiko Sugibayashi, Noboru Sakimura
  • Patent number: 7701267
    Abstract: A semiconductor device including an edge synchronizer which outputs a synchronized strobe signal generated by synchronizing a transition time point of a strobe signal with clock edges of a main clock or a sub clock, a detector which outputs a phase determination signal indicating a phase difference between the main clock and the sub clock in response to the synchronized strobe signal, and a duty ratio corrector which adjusts a duty ratio of the main clock and the sub clock in response to the phase determination signal.
    Type: Grant
    Filed: June 30, 2008
    Date of Patent: April 20, 2010
    Assignee: Hynix Semiconductor, Inc.
    Inventors: Dae-Kun Yoon, Dae-Han Kwon, Chang-Kyu Choi, Jun-Woo Lee
  • Publication number: 20100085096
    Abstract: A system comprises first timing logic configured to produce a first signal and second timing logic configured to produce a second signal. The system also comprises processing logic coupled to the first and second timing logic. The system further comprises clock logic that determines elapsed time using the first signal. The processing logic compares the first and second signals and, based on the comparison, the system adjusts the elapsed time.
    Type: Application
    Filed: January 28, 2009
    Publication date: April 8, 2010
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Nicholas H. SCHUTT, Karl F. GREB
  • Publication number: 20100085091
    Abstract: Embodiments of a proportional phase comparator and method for aligning digital signals are generally described herein. In some embodiments, circuitry to align digital signals comprises a proportional phase comparator that generates triangular-shaped pulses for application to a charge pump. The triangular-shaped pulses may reduce an amount of charge injection in the charge pump close to convergence.
    Type: Application
    Filed: January 15, 2008
    Publication date: April 8, 2010
    Inventors: Franck Strazzieri, Florent Garcia
  • Patent number: 7688116
    Abstract: Circuitry and methods are disclosed for capturing data from a double-data rate signal received from a source circuit, converting the double-data rate signal to single and/or half rate data signals, and re-synchronizing the data to the destination circuit's clock signal. In one embodiment, a first set of registers converts a double-data rate signal synchronized to a full-rate clock signal to two single-data rate signals. A second set of registers converts the single-data rate signals to four half-data rate signals. A third set of registers synchronizes the half-rate data signals to a half-rate clock signal.
    Type: Grant
    Filed: May 9, 2008
    Date of Patent: March 30, 2010
    Assignee: Altera Corporation
    Inventors: Philip Wise, Philip Clarke
  • Publication number: 20100074374
    Abstract: A phase calibration circuit applied to at least one signal processing module group includes at least two phase calibration modules, a phase detection module and a filter module. An output node of a first phase calibration module is coupled to an input node of a first signal processing module, an input node of a second phase calibration module is coupled to an output node of the first signal processing module, and the first signal processing module receives a calibrated signal outputted from the first phase calibration module and generates a processed signal. The phase detection module is utilized for generating a phase error signal according to a calibrated signal of an Mth phase calibration module, where M is an integer equal to or greater than two. The filter module is utilized for generating at least a first and a second phase calibration signal according to the phase error signal.
    Type: Application
    Filed: September 24, 2009
    Publication date: March 25, 2010
    Inventors: Yi-Lin Li, Cheng-Yi Huang
  • Patent number: 7681062
    Abstract: Disclosed is a synchronous semiconductor device including clock generation circuit that frequency divides a clock signal (PCLK) input from an input buffer and generates first and second internal clock signals having a predetermined phase difference from first and second frequency-divided clock signals of different phases, respectively, a first input circuit control unit that receives a chip select signal and samples the chip select signal in synchronization with the clock signal, second and third input circuit control units that sample an output of the first input circuit control unit in synchronization with the first and second internal clock signals, respectively, and first and second input circuits that receive a result of a logic operation between the output of the first input control unit and an output of the second input circuit control unit and a result of a logic operation between the output of the first input circuit control unit and an output of the third input circuit control unit as input enable s
    Type: Grant
    Filed: October 26, 2006
    Date of Patent: March 16, 2010
    Assignee: Elpida Memory, Inc.
    Inventor: Koji Kuroki
  • Publication number: 20100060329
    Abstract: A semiconductor device includes: a clock input unit configured to receive a system clock and a data clock externally; a phase dividing unit configured to generate a plurality of multi-system clocks in response to the system clock, wherein each of the multi-system clocks has an individual phase difference; a phase detecting unit configured to detect phase differences between the plurality of multi-system clock and the data clock and to generating generate a training information signal in response to the detection result; and a signal transmitting unit configured to transmit the training information signal.
    Type: Application
    Filed: December 29, 2008
    Publication date: March 11, 2010
    Inventor: Jung-Hoon PARK
  • Patent number: 7675341
    Abstract: A method and device for generating a clock signal, the method including measuring, using a first clock signal, a characteristic of a reference event in a received signal, determining, using the first clock signal, a variation of a characteristic of a second event in a received signal, correcting the measurement according to the variation of the characteristic of the second event, and generating a second clock signal using the first clock signal according to the corrected measurement.
    Type: Grant
    Filed: March 3, 2008
    Date of Patent: March 9, 2010
    Assignee: STMicroelectronics SA
    Inventors: Christophe Moreaux, Ahmed Kari, David Naura, Pierre Rizzo
  • Patent number: 7668698
    Abstract: Embodiments of the invention are generally directed to systems, methods, and apparatuses for the direct duty cycle calibration of a receiver clock. In some embodiments, an integrated circuit includes a receive (RX) data path, a RX clock path, and a control path. In some embodiments, the control path uses RX latches, a majority detector, and digital duty cycle control logic to calibrate the duty cycle of the clock signal. Other embodiments are described and claimed.
    Type: Grant
    Filed: December 6, 2007
    Date of Patent: February 23, 2010
    Assignee: Intel Corporation
    Inventor: Yueming Jiang
  • Patent number: 7668207
    Abstract: A system, method, and article of manufacture for synchronizing first and second time-of-day clocks on first and second computers, respectively, are provided. The first and second computers have first and second network interface cards with third and fourth clocks, respectively, thereon. The system utilizes time stamp values generated by the third and fourth clocks to synchronize the first and second time-of-day clocks.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: February 23, 2010
    Assignee: International Business Machines Corporation
    Inventors: David F. Craddock, Richard K. Errickson, Thomas A. Gregg, Bruce Marshall Walk
  • Publication number: 20100039147
    Abstract: Semiconductor devices are disclosed providing synchronization circuits for synchronized signal distribution for a plurality of devices in a semiconductor device. The synchronization apparatus includes an independent synchronization circuit and a dependent synchronization circuit. The independent synchronization circuit may be configured to receive a source signal and to generate a first destination signal substantially synchronized with the source signal. The dependent synchronization circuit may be coupled to the independent synchronization circuit and configured to receive the source signal and to generate a second destination signal substantially synchronized with the source signal.
    Type: Application
    Filed: October 19, 2009
    Publication date: February 18, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventor: Seong-hoon Lee
  • Patent number: 7664217
    Abstract: A DPLL circuit is provided for making it possible to inhibit an initial frequency offset during holdover. The DPLL circuit includes a slave oscillator for generating a frequency signal corresponding to the size of a control signal value; a phase difference detection circuit for detecting the difference in phase between the output of said slave oscillator and the inputted reference clock, and outputting a digital signal of the prescribed number of bits corresponding to said detected phase difference; and a holdover unit for generating a correction value based on the output of said phase difference detection circuit, wherein when the holdover is detected, said holdover unit periodically adds the correction value to the output of said phase difference detection circuit to obtain a control value for said slave oscillator.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: February 16, 2010
    Assignee: Fujitsu Limited
    Inventors: Koji Nakamuta, Yoshito Koyama
  • Patent number: 7659757
    Abstract: A clock regeneration circuit and method including an asynchronous clock signal input to a meta-stability filtering circuit, a synchronous clock signal input to the meta-stability filtering circuit with a frequency lower than the asynchronous clock signal, and being over-sampled and rate adapted to the asynchronous clock signal, an edge detector detecting an edge of the output of the meta-stability filtering circuit, a regenerated clock signal output therefrom, and a clock regeneration stage receiving an input that is the edge-detected output.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: February 9, 2010
    Assignee: Alcatel Lucent
    Inventors: Todd Sleigh, Steve Driediger
  • Publication number: 20100026350
    Abstract: A clock/data recovery device 1 comprises a sampler 10, a detector 20, an offset determination part 30, a clock output part 40, and a DA converter 50. The phases of clock signals CK and CKX are adjusted so as to match with the phase of an input digital signal. An offset amount (±Voff) added in the sampler 10 is adjusted so as to match with a peak time of a data transition time distribution of a first signal in a case where a value D(n?1) is HIGH level, and is adjusted so as to match with a peak time of a data transition time distribution of a second signal in a case where the value D(n?1) is LOW level. Either of the clock signals CK and CKX is outputted as the recovered clock signal. Time series data of a digital value D(n) is outputted as the recovered data.
    Type: Application
    Filed: September 6, 2007
    Publication date: February 4, 2010
    Applicant: THINE ELECTRONICS, INC.
    Inventor: Seiichi Ozawa
  • Publication number: 20100022885
    Abstract: A switching DC converting device includes a switching DC converter and a synchronous clock circuit. The synchronous clock circuit is used to provide a wobbling synchronous clock input for the switching DC converter, and the central frequency of the wobbling synchronous clock avoids the operating frequency of a circuit powered by the switching DC converter.
    Type: Application
    Filed: July 24, 2009
    Publication date: January 28, 2010
    Inventor: Feng Wu
  • Patent number: 7652512
    Abstract: A clock synchronizing circuit applied in a SMD block is provided. The clock synchronizing circuit includes a number of stages of clock synchronizing units. The clock synchronizing circuit can achieve the purpose of clock synchronizing by using a novel circuit design of the forward delay unit, the mirror control unit or the backward delay unit in each stage of clock synchronizing unit or by using a short-pulse generation circuit to generate a short pulse for triggering out an output clock of each stage of forward delay unit.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: January 26, 2010
    Assignee: Macronix International Co., Ltd.
    Inventors: Wen-Chiao Ho, Chin-Hung Chang, Kuen-Long Chang, Chun-Hsiung Hung
  • Patent number: 7649391
    Abstract: A clock signal transmission circuit having a variable initial value for a wait time that is required until a clock signal stabilizes. The clock signal is generated from an original clock signal. The wait time setting unit generates a plurality of wait time signals to wait until the original clock signal stabilizes before providing the clock signal to the internal circuit. A wait time determination unit selects one of the wait time signals and provides the selected wait time signal to a clock control unit. The wait time determination unit includes a data holding circuit which generates a selection signal in accordance with the initial value, a selection circuit which selects one of the wait time signals based on the selection circuit, and an initial value setting circuit enabling the initial value to be varied.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: January 19, 2010
    Assignee: Fujitsu Microelectronics Limited
    Inventor: Ryoko Ozao
  • Patent number: 7647520
    Abstract: The invention relates to electronic devices for generating synchronization signals, in particular to ultrahigh resolution synchronization signals whose temporal accuracy is less than a nanosecond. The inventive device operates not only with an internal clock but also with the external clock of a synchronizable device, thereby avoiding any temporal drift and uncertainty of the synchronization signals. The main element of the device is embodied in the form of a programmable digital component which operates with the external clock frequency and comprises programmable delay lines enabling to attain ultrahigh temporal resolutions. Said invention also relates to a system comprising several synchronization devices which are interconnected in such a way that the synchronization of different devices remains perfect. The invention makes it possible to control with high accuracy a quasi-unlimited number of devices.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: January 12, 2010
    Assignee: Thales
    Inventor: Patrick Lefebvre
  • Patent number: 7643602
    Abstract: A method is provided for estimating a frequency offset value. This method includes: receiving a signal from the transmitting device at the receiving device, the received signal having a transmitter frequency (510); generating a local signal at the receiving device, the local signal having a starting frequency (520); comparing a received signal phase and a local signal phase to determine an adjusted error signal representing a phase difference between the received signal and the local signal (530); adjusting a current frequency of the local signal from the starting frequency to the transmitting frequency over a time period (540); integrating the adjusted error signal over the time period to generate an integrated error signal (550); and filtering the integrated error signal to generate a frequency difference estimate indicative of the frequency difference between the transmitter frequency and the starting frequency (560).
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: January 5, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Timothy R. Miller, John W. McCorkle
  • Patent number: RE41337
    Abstract: The entire data path of a synchronous integrated circuit device is initialized in a test mode upon power-up of the synchronous integrated circuit device. Upon power-up of the integrated circuit device in the test mode, a clock signal (either an external clock signal or an associated internal clock signal) is internally clocked. As the clock signal goes to a low logic state upon power-up of the device, a master latch (flip-flop) flip-flop element of the integrated circuit device is loaded with data and is allowed to conduct; a slave latch (flip-flop) flip-flop element of the integrated circuit device does not conduct. As the clock signal goes to a high logic state, the data in the master latch is latched. Also upon the high logic state of the clock, the slave latch element is loaded with data and is allowed to conduct.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: May 18, 2010
    Assignee: STMicroelectronics, Inc.
    Inventor: David Charles McClure