Phase Locking Patents (Class 375/373)
  • Publication number: 20150071396
    Abstract: For each of a plurality of delayed phases, one of the plurality of delayed phases being the same as a phase of a reference clock and the others of the plurality of delayed phases delayed with respect to the phase of the reference clock, test parallel data transmitted in synchronism with the reference clock is received in synchronism with a delayed clock having the delayed phase and an adjacent delayed clock having a delayed phase adjacent to the delayed phase of the delayed clock, respectively; and a phase range containing a delayed phase with which the test parallel data has been received correctly and for which the result of the comparison indicates a match is determined from among the plurality of delayed phases; and the phase of a receive clock to be used for reception of parallel data is determined from the determined phase range.
    Type: Application
    Filed: August 13, 2014
    Publication date: March 12, 2015
    Inventor: Ryoichi INAGAWA
  • Patent number: 8976054
    Abstract: A time-to-digital conversion circuit for converting a time difference between two input signals to a 1-bit digital value, and adjusting the time difference between the two input signals to generate two output signals includes: a phase comparator configured to compare phases of the two input signals with each other to generate the digital value; a phase selector configured to output one of the two input signals which has a leading phase as a first signal, and the other of the two input signals which has a lagging phase as a second signal; and a delay unit configured to output the first signal with a delay, wherein the time-to-digital conversion circuit outputs the signal output from the delay unit and the second signal as the two output signals.
    Type: Grant
    Filed: July 15, 2013
    Date of Patent: March 10, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Shiro Dosho, Masao Takayama, Takuji Miki
  • Patent number: 8976051
    Abstract: Aspects of the present disclosure relate to floating point timers and counters that are used in a variety of contexts. In some implementations, a floating point counter can be used to generate a wave form made up of a series of pulses with different pulse lengths. An array of these floating point counters can be used to implement a pool of delays. In other implementations, an array of floating point counters can be used to analyze waveforms on a number of different communication channels. Analysis of such waveforms may be useful in automotive applications, such as in wheel speed measurement for example, as well as other applications.
    Type: Grant
    Filed: June 5, 2012
    Date of Patent: March 10, 2015
    Assignee: Infineon Technologies AG
    Inventors: Ljudmil Anastasov, Jens Barrenscheen
  • Publication number: 20150063516
    Abstract: A communication circuit includes: a plurality of receiving units each configured to receive a serial signal over a transmission path from another device; a plurality of serial-to-parallel converters each configured to convert the received serial signal into a parallel signal; and a clock phase controller configured to send a clock phase control signal to any of the plurality of serial-to-parallel converters, wherein one of the serial-to-parallel converters that has received the clock phase control signal is configured to shift a phase of a parallel-signal clock signal that is to be used for a parallel signal obtained by conversion, so that a phase of a parallel signal to be obtained by conversion performed by the one of the serial-to-parallel converters is different from a phase of a parallel signal to be obtained by conversion performed by another one of the serial-to-parallel converters.
    Type: Application
    Filed: July 25, 2014
    Publication date: March 5, 2015
    Applicant: FUJITSU LIMITED
    Inventor: Ryuichi Nishiyama
  • Patent number: 8971469
    Abstract: A master device and slave devices are connected with each other through an SDA and an SCL, and at least one of a serial communication data signal communicated through the SDA and a serial communication clock signal communicated through the SCL is latched with use of a noise removal clock signal whose frequency is higher than that of the serial communication clock signal, and is taken in.
    Type: Grant
    Filed: August 24, 2011
    Date of Patent: March 3, 2015
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masahiro Imai, Nobuaki Takahashi
  • Patent number: 8964922
    Abstract: Various embodiments of the present invention relate to systems, devices and methods of oversampling electronic components where high frequency oversampling clock signals are generated internally. The generated oversampling clock is automatically synchronous with the input clock and the input serial data in a serial data link, and is adaptive to predetermined parameters, such as bit depth and oversampling rate.
    Type: Grant
    Filed: August 6, 2013
    Date of Patent: February 24, 2015
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Matthew Felder, Mark Summers
  • Patent number: 8964925
    Abstract: Methods and systems to generate control signals for timing recovery of a signal received over baseband communications systems are disclosed. The timing control circuit uses a multi-rate DSP structure for the implementation of the DSP functions in the control loop for use in an ASIC and requires a reduced DSP clock rate, which in turn reduces the need for pipelining and/or high-speed libraries. Thus lower latency, better tracking performance and lower power consumption are achieved. An example embodiment involves splitting the timing error signal, supplied at a given update rate, into a sum and a difference component, and processing each component in separate circuit chains at half the update rate. The resultant half-rate control signals from each separate circuit chain are joined to provide a control signal at the full update rate. Thus, implementations of the present disclosure perform like a full-rate structure, but require a halved DSP clock rate.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: February 24, 2015
    Assignee: PMC-Sierra US, Inc.
    Inventor: Aryan Saed
  • Patent number: 8964899
    Abstract: Disclosed is a receiving circuit which includes: a data selection circuit selecting two input data located while placing in between the center phase of one unit interval of a binary input data; a correction circuit correcting the two input data selected by the data selection circuit; a phase detection circuit detecting a phase at which the level of input data changes as a boundary phase in the one unit interval, based on the two input data corrected by the correction circuit; an arithmetic unit calculating the center phase, based on the boundary phase detected by the phase detection circuit; and data decision circuit determining and outputting the level of one of the two input data, based on the center phase and the boundary phase, the correction circuit implements the correction based on a correction value corresponded to the past data level output by the data decision circuit.
    Type: Grant
    Filed: October 25, 2012
    Date of Patent: February 24, 2015
    Assignee: Fujitsu Limited
    Inventor: Hirotaka Tamura
  • Patent number: 8964921
    Abstract: The present invention relates to an information processing apparatus, a method, and a program capable of suppressing deterioration of content quality. An integrated reception buffer time adjustment unit 114 obtains a maximum transmission delay time that is the longest delay time among the transmission delays of data transmission performed by each reception unit 113. The reception buffer time setting unit 208 calculates a reception buffer time using the maximum transmission delay time, a transmission delay time of the data transmission by the reception unit 113, and a prescribed reception buffer time. The reception buffer time setting unit 208 sets various delay times and waiting times such as a variable compression encoding delay time, a redundant encoding block reception waiting time, an ARQ retransmission packet waiting time, and a network jitter handling buffer time from the reception buffer time. The present invention can be applied to an information processing apparatus, for example.
    Type: Grant
    Filed: August 3, 2011
    Date of Patent: February 24, 2015
    Assignee: Sony Corporation
    Inventors: Yoshinobu Kure, Hideaki Murayama, Tamotsu Munakata, Chihiro Fujita, Osamu Yoshimura
  • Patent number: 8958513
    Abstract: A device and method for clock and data recovery are disclosed. For example, an integrated circuit comprises a first branch for recovering a clock signal from an input signal. The first branch includes a phase and frequency detector for detecting a phase and a frequency of the clock signal and a numerically controlled oscillator that is controlled by the phase and the frequency of the clock signal from the phase and frequency detector. The integrated circuit also includes a second branch for recovering a data signal from the input signal. The second branch includes a pre-settable numerically controlled oscillator that is pre-settable with the phase and the frequency of the clock signal from the numerically controlled oscillator. The second branch also includes a sample selector that is controlled by the pre-settable numerically controlled oscillator for recovering the data signal.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: February 17, 2015
    Assignee: Xilinx, Inc.
    Inventors: Paolo Novellini, Martin J. Kellermann
  • Patent number: 8958515
    Abstract: A system for controllably generating jitter in a serial data stream includes a frequency generator and first and second mixers. The frequency generator is configured to output in-phase and quadrature local oscillator signals with a local oscillator frequency of at least about 5 MHz. The local oscillator frequency varies between a selectable minimum frequency and a selectable maximum frequency. The first mixer is configured to mix a fixed frequency clock signal with the in-phase local oscillator signal to output a first mixer output. The second mixer is configured to mix the fixed frequency clock signal with the quadrature local oscillator signal to output a second mixer output. An adder is configured to add the first and second mixer outputs to produce a frequency-modulated clock signal with a frequency that is about the sum of the fixed frequency and the local oscillator frequency and includes a periodic jitter.
    Type: Grant
    Filed: April 28, 2011
    Date of Patent: February 17, 2015
    Assignee: LSI Corporation
    Inventors: Yi Cai, Ivan Chan, Liming Fang, Max J. Olsen
  • Patent number: 8953730
    Abstract: A phase locked loop includes a phase difference detector configured to receive a reference frequency and a divider frequency and output a phase difference signal. The phase locked loop includes a code generator configured to receive the reference frequency and the phase difference signal, and output a coarse tuning signal and a reset signal. The phase locked loop includes a digital loop filter configured to receive the phase difference signal and output a fine tuning signal. The phase locked loop includes a voltage control oscillator configured to receive the coarse and fine tuning signals, and output an output frequency. The phase locked loop includes a divider configured to receive the reset signal, a divider number control signal and the output frequency, and output the divider frequency. The phase locked loop includes a delta-sigma modulator configured to receive a divisor ratio and the reset signal, and output divider number control signal.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: February 10, 2015
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Yen-Jen Chen, Feng Wei Kuo, Huan-Neng Chen, Chewn-Pu Jou
  • Patent number: 8948331
    Abstract: Embodiments of circuits and methods are described for decreasing transmitter waveform dispersion penalty (TWDP) in a transmitter. A data stream is received for transmission across a channel and a main data signal is generated from the data stream. At least two cursor signals are generated where each of the at least two cursor signals are shifted at least a portion of a clock period from the main data signal. The at least two cursor signals are subtracted from the main data signal to generate an output data signal with improved TWDP. Other embodiments include generating a main data signal, a pre-cursor signal shifted on previous clock cycle relative to the main data signal, and a post-cursor signal Shifted one subsequent clock cycle relative to the main data signal. The pre and post cursor signals are subtracted from the main data signal to generate an output data signal.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: February 3, 2015
    Assignee: Netlogic Microsystems, Inc.
    Inventors: Halil Cirit, Stefanos Sidiropoulos
  • Patent number: 8948332
    Abstract: A method for calibrating a clock and data recovery circuit may include configuring a phase detector as a bang-bang phase detector. The bang-bang phase detector may be used to determine a phase difference between a sampling clock provided by an interpolator and a calibration signal. The phase detector may also be configured as a linear phase detector. While using the linear phase detector, a linear phase detector parameter may be adjusted such that the phase difference between the calibration signal and the sampling clock is zero, while keeping the phase of the sampling clock fixed.
    Type: Grant
    Filed: November 16, 2012
    Date of Patent: February 3, 2015
    Assignee: Analog Devices, Inc.
    Inventors: John Kenney, Jeremy Z. Walker
  • Patent number: 8942333
    Abstract: Apparatuses and methods for phase aligning at least two clocks used by respective first and second circuitry systems, such as a memory controller and a DDR PHY interface in a system on a chip system. A first circuit samples a phase of a first clock used by the first circuitry system, and then a delay circuit selectively delays a second clock used by the second circuitry system and sets a delayed timing of the second clock. To economize resources and reduce chip area, a logic circuit receives the sampled phase of the first clock, determines which delayed timing matches timing of the sampled phase, and sets the delay circuit to a fixed delayed timing corresponding to the delayed timing that matches the sampled phase. Thus, phase alignment of the two clocks is achieved with fewer resources.
    Type: Grant
    Filed: November 12, 2012
    Date of Patent: January 27, 2015
    Assignee: Texas Instruments Incorporated
    Inventors: Arvind Kumar, Shobhit Singhal, Vikas Lakhanpal, Kalpesh Amrutlal Shah
  • Patent number: 8942324
    Abstract: A circuit, use, and method for controlling a receiver circuit is provided, wherein a complex baseband signal is generated from a received signal, a phase difference between a phase of the complex baseband signal and a phase precalculated from previous sampled values is determined, the phase difference is compared with a first threshold, a number is determined by counting the exceedances of the first threshold by the phase difference, a number of the counted exceedances is compared with a second threshold, and the receiver circuit is turned off if the number of counted exceedances exceeds the second threshold within a time period.
    Type: Grant
    Filed: December 30, 2013
    Date of Patent: January 27, 2015
    Assignee: Atmel Corporation
    Inventors: Ulrich Grosskinsky, Werner Blatz
  • Patent number: 8942280
    Abstract: A timing jitter measurement circuit for measuring timing jitter in the digital domain may use an interpolator bank to over-sample a signal from a media reader, a zero crossing estimator to estimate a zero crossing moment in the output of the interpolator bank and a time interval analyzer (TIA) to calculate the timing jitter as the deviation of the estimated zero crossing moment from an expected zero crossing moment in a clock signal. The timing jitter measurement circuit may be integrated into digital circuitry since it avoids using analog devices. Consequently, it may simplify the chip design, lower power consumption and save space.
    Type: Grant
    Filed: February 6, 2014
    Date of Patent: January 27, 2015
    Assignee: Marvell International Ltd.
    Inventors: Mats Oberg, Jin Xie, Bin Ni
  • Patent number: 8942314
    Abstract: A method for Tx interference cancellation and power detection in a wireless device is described. A portion of a Tx output signal is down-converted to generate a feedback signal. A reconstructed interference signal and a weight are generated based on the feedback signal. A Tx power level is detected based on the weight. The reconstructed interference signal is subtracted from the Tx output signal.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: January 27, 2015
    Assignee: QUALCOMM Incorporated
    Inventor: Vladimir Aparin
  • Patent number: 8929467
    Abstract: A one-wire communication bus for transferring a sequence of digital data from a transmitter to a receiver includes (a) an ECDD signal modulation circuit to create an electrical pulse train wherein each pulse's edge is used as clock signal and each pulse's duty cycle is used to represent digital value of zero and one; (b) an ECDD signal demodulation circuit to receive the ECDD pulse train using a group of sampling cells and to decode the sampled results using a majority voting circuit; (c) an electrical connection between a transmitter wherein the ECDD signal modulation circuit resides and a receiver wherein the ECDD signal demodulation circuit resides. Said ECDD signal is sent from the transmitter to the receiver through the electrical connection. Methods of creating the ECDD pulse train in the transmitter and decoding the ECDD pulse train in the receiver are also disclosed.
    Type: Grant
    Filed: January 13, 2014
    Date of Patent: January 6, 2015
    Inventor: Liming Xiu
  • Patent number: 8923466
    Abstract: A multi-phase clock switching device includes a plurality of phase selection circuits. The phase selection circuit is used to receive a plurality of phase clock signals and determine how to output the phase clock signals to generate an output signal according to a switching signal. The phase selection circuit includes a selection unit and a protection unit. The selection unit receives at least a phase clock signal and determines how to output a phase clock signal according to the at least a phase clock signal and a selection signal. The protection unit determines how to generate the selection signal according to the phase clock signal and the switching signal.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: December 30, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventor: Ming-Cheng Chiang
  • Patent number: 8923465
    Abstract: A semiconductor device comprises sampling logic, comprising: input sample path selection logic arranged to enable at least one input sample path; sampler logic arranged to receive and sample an input data signal in a serial data stream in accordance with a phase of the at least one enabled input sample path; and transition detection logic arranged to detect transitions within the received input data signal. The input sample path selection logic is further arranged, upon detection of a transition within the received input data signal, to determine if the phase of the at least one input sample path is a phase having a largest window between logic values; and if it is determined that the phase of the at least one input sample path is not the phase having a largest window between logic values, to enable at least one input sample path comprising a more appropriate phase.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: December 30, 2014
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Conor O'Keeffe, Kiyoshi Kase, Paul Kelleher
  • Patent number: 8917805
    Abstract: Frequency multipliers include a pair of transistors each connected to a common impedance through a respective collector impedance formed from a transmission line. Each transmission line has a length between about one quarter and about one eighth of a wavelength of an input signal frequency and is tuned to produce a large impedance at a collector of the respective transistor at the input signal frequency. The output frequency between the collector impedances and the common impedance is an even integer multiple of the input frequency.
    Type: Grant
    Filed: November 20, 2012
    Date of Patent: December 23, 2014
    Assignee: International Business Machines Corporation
    Inventors: Wooram Lee, Alberto Valdes Garcia
  • Patent number: 8897408
    Abstract: A method for operating an automation system with a plurality of communication users linked for communication purposes via a serial connection, of which at least one functions as sender and at least one as a receiver, includes determining at a sender an offset value between an occurrence of a synchronous signal and a communication clock cycle, transmitting the determined offset value in a data transmission to the at least one receiver, waiting at the at least one receiver until a time period commensurate with the offset value has elapsed, and generating at the at least one receiver an output signal after the time period has elapsed.
    Type: Grant
    Filed: May 25, 2012
    Date of Patent: November 25, 2014
    Assignee: Siemens Aktiengesellschaft
    Inventor: Peter Jänicke
  • Patent number: 8897411
    Abstract: A delay compensation circuit for a delay locked loop which includes a main delay line having a fine delay line comprising fine delay elements and a coarse delay line comprising coarse delay elements, the main delay line being controlled by a controller, the delay compensation circuit comprising: an adjustable fine delay for modeling a coarse delay element, a counter for controlling the adjustable fine delay to a value which is substantially the same as that of a coarse delay element, a circuit for applying a representation of the system clock to the delay compensation circuit, and a circuit for applying the fine delay count from the counter to the controller for adjusting the fine delay line of the main delay line to a value which is substantially the same as that of a coarse delay element of the main delay line.
    Type: Grant
    Filed: January 15, 2013
    Date of Patent: November 25, 2014
    Assignee: Conversant Intellectual Property Management Inc.
    Inventors: Gurpreet Bhullar, Graham Allan
  • Patent number: 8892430
    Abstract: A difference signal calculating unit of a noise detecting device calculates a difference between the amplitudes of a residual signal at each sample timing and a residual signal at the preceding sample timing. A difference signal comparing unit determines whether or not an impulsive noise is present on the basis of the difference signal at the current sample timing, and the difference signal at each sample timing within a predetermined duration from the current sample timing.
    Type: Grant
    Filed: April 22, 2009
    Date of Patent: November 18, 2014
    Assignee: Fujitsu Limited
    Inventors: Masakiyo Tanaka, Takeshi Otani, Shusaku Ito
  • Patent number: 8891667
    Abstract: A transmission apparatus for transmitting frames accommodating client data over a transmission network, comprising a clock generation unit that generates a clock for timing processing period of signal processing, a deviation detection unit that detects clock deviation between the clock generated by the clock generation unit and the clock used for timing processing period of signal processing by other transmission apparatus that receives the client data from outside the transmission network and adds them to frames, and a timing generation unit that generates timing signal of processing period of signal processing corrected with the clock deviation.
    Type: Grant
    Filed: March 7, 2013
    Date of Patent: November 18, 2014
    Assignee: Fujitsu Limited
    Inventors: Junichi Sugiyama, Makoto Shimizu, Wataru Odashima, Shota Shinohara, Hiroyuki Homma
  • Patent number: 8890590
    Abstract: A wideband frequency synthesizer and a frequency synthesizing method thereof are provided. The wideband frequency synthesizer includes a phase-locked loop unit, a first voltage-controlled oscillating unit and a first frequency mixer unit. The phase-locked loop unit receives a reference signal and a feedback signal and generates a first oscillating signal according to the reference signal and the feedback signal. The first voltage-controlled oscillating unit generates a second oscillating signal. The first frequency mixer is coupled to the phase-locked loop unit and the first voltage-controlled oscillating unit, receives the first oscillating signal and the second oscillating signal for mixing frequencies of the first oscillating signal and the second oscillating signal to generate an output signal and taking the output signal as the feedback signal for outputting to the phase-locked loop unit.
    Type: Grant
    Filed: August 8, 2013
    Date of Patent: November 18, 2014
    Assignee: National Sun Yat-sen University
    Inventors: Tzyy-Sheng Horng, Kang-Chun Peng, Fu-Kang Wang
  • Patent number: 8890589
    Abstract: An apparatus for measuring a high speed signal may comprise a plurality of Analog-Digital converters (AD converter) that are arranged in parallel to each other to sample an input signal at different frequencies; a plurality of frequency synthesizers configured to provide each AD converter with a different sampling frequency; a signal processor configured to receive an output of the plurality of AD converters to reconstruct the input signal; and/or a controller configured to receive and process a trigger signal.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: November 18, 2014
    Assignees: Samsung Electronics Co., Ltd., Georgia Tech Research Corporation
    Inventors: Sung Yeol Kim, Hyun Woo Choi, Nicholas Tzou, Xian Wang, Thomas Moon, Abhijit Chatterjee, Ho Sun Yoo
  • Patent number: 8891717
    Abstract: One bit is a smallest increment of binary measurement in first and second digital values. The first digital value is converted into a first analog signal. The second digital value is converted into a second analog signal. The first analog signal is augmented by a first amount that equates to less than the smallest increment of binary measurement, so that the augmented first analog signal by definition does not equal the second analog signal. The second analog signal is augmented by a second amount that equates to less than the smallest increment of binary measurement, so that the augmented second analog signal by definition does not equal the first analog signal. The augmented first analog signal is compared to the second analog signal, and a first signal is output in response thereto. The augmented second analog signal is compared to the first analog signal, and a second signal is output in response thereto.
    Type: Grant
    Filed: July 30, 2013
    Date of Patent: November 18, 2014
    Assignee: Texas Instruments Incorporated
    Inventor: Robert Floyd Payne
  • Patent number: 8885776
    Abstract: A symbol error detector can be configured to detect symbol errors of a Bluetooth enhanced data rate (EDR) packet without relying solely on a CRC error detection mechanism. After a phase of a current symbol is demodulated to determine a demodulated current symbol, the phase of the demodulated current symbol can be subtracted from the phase of the current symbol prior to demodulation to yield a phase error. The phase error can be compared against a phase error threshold to determine a potential unreliability of the demodulated current symbol. The phase error being greater than the phase error threshold can indicate that the demodulated current symbol may be unreliable. Accordingly, a symbol error notification can be generated to indicate that the demodulated current symbol may be unreliable.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: November 11, 2014
    Assignee: QUALCOMM Incorporated
    Inventor: Soner Ozgur
  • Patent number: 8885787
    Abstract: A clock and data recovery (CDR) circuit includes an inductor-capacitor voltage controlled oscillator (LCVCO) configured to generate a clock signal with a clock frequency. The CDR circuit further includes a delay locked loop (DLL) configured to receive the clock signal from the LCVCO and generate multiple clock phases and a first charge pump configured to control the LCVCO. The CDR circuit further includes a phase detector configured to receive a data input and the multiple clock phases from the DLL, and to align a data edge of the data input and the multiple clock phases.
    Type: Grant
    Filed: October 21, 2013
    Date of Patent: November 11, 2014
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Chan-Hong Chern, Chih-Chang Lin, Ming-Chieh Huang, Fu-Lung Hsueh
  • Patent number: 8879681
    Abstract: A system and method are provided for determining a time for safely sampling a signal of a dock domain. In one embodiment, a frequency estimate of a first clock domain is calculated utilizing a frequency estimator. Additionally, a time during which a signal from the first clock domain is unchanging is determined such that the signal is capable of being safely sampled by a second clock domain, using the frequency estimate. In another embodiment, a frequency estimate of a first dock domain is calculated utilizing a frequency estimator. Further, a phase estimate of the first clock domain is calculated based on the frequency estimate, utilizing a phase estimator. Moreover, a time during which a signal from the first clock domain is unchanging is determined such that the signal is capable of being safely sampled by a second clock domain, using the phase estimate.
    Type: Grant
    Filed: March 22, 2013
    Date of Patent: November 4, 2014
    Assignee: NVIDIA Corporation
    Inventors: William J. Dally, Stephen G. Tell
  • Patent number: 8873692
    Abstract: Clock compensation for GPS receivers. A receiver in accordance with the present invention comprises a Radio Frequency (RF) portion, and a baseband portion, coupled to the RF portion, wherein the baseband portion comprises a crystal, an oscillator, coupled to the crystal, wherein the oscillator generates a clock signal based on a signal received from the crystal, a counter, coupled to the oscillator via the clock signal, a comparator, coupled to the counter, a controller, at least one logic gate, coupled to the comparator and the controller, and a combiner, coupled to the at least one logic gate, the controller, and the counter and producing an accurate clock signal therefrom.
    Type: Grant
    Filed: January 17, 2012
    Date of Patent: October 28, 2014
    Assignee: Qualcomm Incorporated
    Inventor: Richard Obermeyer
  • Patent number: 8873693
    Abstract: In one embodiment, a method includes adjusting a first frequency of a first clock signal based on a frequency difference between the first frequency and a reference clock signal frequency of a reference clock signal, and further adjusting the first frequency and a first phase of the first clock signal based on a phase difference between the first clock signal and an input data bit stream and the frequency difference between the first frequency and the reference clock signal frequency to substantially lock the first frequency and the first phase of the first clock signal to the input data bit frequency and input data bit phase of the input data bit stream.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: October 28, 2014
    Assignee: Fujitsu Limited
    Inventor: Nikola Nedovic
  • Publication number: 20140314193
    Abstract: A method of receiving wireless data is provided. The method includes generating a plurality of local clocks having different delayed phases with respect to a carrier wave during a carrier wave period and receiving a data packet using the plurality of local clocks. The plurality of local clocks includes at least a first local clock and a second local clock. The first local clock has a 0 degree delayed phase with respect to the carrier wave. The second local clock has a 90 degree delayed phase with respect to the carrier wave.
    Type: Application
    Filed: April 16, 2014
    Publication date: October 23, 2014
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Hyuk-Jun Sung
  • Patent number: 8867597
    Abstract: The present invention discloses a clock dejitter method comprising: a data sending adapter module inputting data with a system clock and using a sending clock to send data; a clock dejitter module associating the system clock with the sending clock of the data sending adapter module using; and the clock dejitter module tracking variations in the system clock and a data enable signal reflecting data sending state by referring to the system clock, and dynamically generating the sending clock varying with the data sending state. The present invention also discloses a clock dejitter apparatus and a data transmission system. The present invention greatly improves the free scheduling processing ability of services and reduces the bit error rate of data transmission while increasing efficiency of large capacity data switch transmission by dynamically adjusting the sending clock.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: October 21, 2014
    Assignee: ZTE Corporation
    Inventor: Xiaoyi Wei
  • Patent number: 8866520
    Abstract: One embodiment relates to a fracture-able PLL circuit. The fracture-able PLL circuit includes a first phase-locked loop circuit generating a first frequency output, a second phase-locked loop circuit; arranged to generate a second frequency output, and a plurality of shared output resources. Reconfigurable circuitry is arranged so that either of the first and second frequency outputs is receivable by each of the plurality of shared output resources. Another embodiment relates to an integrated circuit which includes a plurality of PMA modules, a plurality of multiple-purpose PLL circuits, and a programmable clock network. The programmable clock network is arranged to allow the clock signals output by the multiple-purpose PLL circuits to be selectively used either by the PMA modules for a transceiver application or by other circuitry for a non-transceiver application. Other embodiments and features are also disclosed.
    Type: Grant
    Filed: September 10, 2013
    Date of Patent: October 21, 2014
    Assignee: Altera Corporation
    Inventors: Tien Duc Pham, Sergey Shumarayev, Richard G. Cliff
  • Patent number: 8867684
    Abstract: An apparatus for synchronizing an incoming signal with a clock signal comprises two or more synchronizer circuits, wherein each synchronizer circuit receives the incoming signal and the clock signal. Each synchronizer circuit generates a synchronized signal, wherein the state of each synchronized signal changes on a different phase of said clock signal in response to a change of the state of said incoming signal. A decision mechanism circuit receives the synchronized signals generated by each synchronizer circuit, wherein the decision mechanism circuit determines the output signal in response to the change of the state of the incoming signal. The decision mechanism circuit further comprises a memory element having a state which is set according to a previously detected state of said signal, wherein the output signal is determined according to the state of the memory element.
    Type: Grant
    Filed: September 5, 2013
    Date of Patent: October 21, 2014
    Assignee: Dialog Semiconductor GmbH
    Inventor: Nir Dahan
  • Patent number: 8860479
    Abstract: Integrated clock differential buffering. A first phase locked loop (PLL) circuit having a first clocking ratio is coupled to receive an input differential clock signal. The first PLL circuit generates a first reference clock signal. A second PLL circuit having a second clocking ratio is coupled to receive the input differential clock signal. The second PLL circuit to generate a second reference clock signal. A first set of clock signal output buffers are coupled to receive the first reference clock signal and to provide a first differential reference clock signal corresponding to the first reference clock signal. A second set of clock signal output buffers is coupled to receive the second reference clock signal and to provide a second differential reference clock signal corresponding to the second reference clock signal.
    Type: Grant
    Filed: June 27, 2013
    Date of Patent: October 14, 2014
    Assignee: Intel Corporation
    Inventors: Choupin Huang, Vijaya K. Boddu, Stefan Rusu, Nicholas B Peterson
  • Patent number: 8861580
    Abstract: Methods and apparatus are provided for determining one or more channel compensation parameters based on data eye monitoring. According to one aspect of the invention, a method is provided for evaluating the quality of a data eye associated with a signal. The received signal is sampled for a plurality of different phases, for example, using at least two latches, and the samples are evaluated to identify when the signal crosses a predefined amplitude value, such as a zero crossing. It is determined whether the points of predefined amplitude crossing satisfy one or more predefined criteria. One or more parameters of one or more channel compensation techniques can optionally be adjusted based on a result of the determining step. One or more parameters of an adjacent transmitter can also be adjusted to reduce near end cross talk based on a result of the determining step.
    Type: Grant
    Filed: May 16, 2006
    Date of Patent: October 14, 2014
    Assignee: Agere Systems LLC
    Inventors: Christopher J. Abel, Mohammad S. Mobin, Gregory W. Sheets, Lane A. Smith
  • Patent number: 8855255
    Abstract: Systems and methods are provided for performing the required phase calculation in a telecommunications system in order to optimize system performance more quickly and with reduced complexity as compared to prior approaches to solving this problem. In accordance with the preferred exemplary embodiment of the present invention, the phase delay of the precursor equalizer (EQ) is calculated off-line and as a result it is not necessary to fill the precursor EQ delay line with the indicated number of symbols as in the previous approach. Additionally, because the precursor EQ is fractionally spaced, both sine and cosine values of the 4kHz tone's initial phase can be achieved simultaneously. As a result, only 36 quick timing sequence (QTS) symbols are needed in order to perform the required estimation.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: October 7, 2014
    Assignee: U.S. Robotics Corp.
    Inventors: Qing Chen, Qian Cheng
  • Patent number: 8855258
    Abstract: A system and method are provided for resynchronizing a transmission signal using a jitter-attenuated clock derived from an asynchronous gapped clock. A first-in first-out (FIFO) memory accepts an asynchronous gapped clock derived from a first clock having a first frequency. The gapped clock has an average second frequency less than the first frequency. The input serial stream of data is loaded at a rate responsive to the gapped clock. A dynamic numerator (DN) and dynamic denominator (DD) are iteratively calculated for the gapped clock, averaged, and an averaged numerator (A and an averaged denominator (AD) are generated. The first frequency is multiplied by the ratio of AN/AD to create a jitter-attenuated second clock having the second frequency. The FIFO memory accepts the jitter-attenuated second clock and supplies data from memory at the second frequency. A framer accepts the data from the FIFO memory and the jitter-attenuated second clock.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: October 7, 2014
    Assignee: Applied Micro Circuits Corporation
    Inventors: Viet Do, Simon Pang
  • Patent number: 8850257
    Abstract: A method and device for preventing a defect in a CDR circuit from hindering synchronization between connection nodes and for preventing connection failures. The CDR circuit generates a synchronization clock from received data. A connection failure processor performs a connection failure process if synchronization based on the synchronization clock between connection nodes is not established when a first predetermined time from when the reception of the received data is started elapses. A correction processor corrects operation of the CDR circuit if synchronization based on the synchronization clock between connection nodes is not established when a second predetermined time, which is shorter than the first predetermined time, from when the reception of the received data is started elapses.
    Type: Grant
    Filed: June 26, 2013
    Date of Patent: September 30, 2014
    Assignee: Spansion LLC
    Inventor: Masato Tomita
  • Patent number: 8848851
    Abstract: An output signal adjustment system includes a signal adjustment unit, a reference slope generating unit, a slope detecting unit, a voltage-to-current conversion unit, and a control unit. The slope detecting unit compares the slope of the rising and falling edges of the output signal of the reference slope generating unit with that of the signal adjustment unit and outputs a voltage signal. The voltage-to-current conversion unit converts the voltage signal into a current signal. Based on the current signal, the control unit outputs a control signal for controlling the adjustment of the signal adjustment unit to the slope of the rising and falling edges of the output signal. The output signal adjustment system can automatically adjust the slope of the rising and falling edges of the output signal, so that the output signal is insensitive to the packaging, the printed circuit board, the transmission line and other sender loads.
    Type: Grant
    Filed: August 10, 2011
    Date of Patent: September 30, 2014
    Assignee: IPGoal Microelectronics (SIChuan) Co., Ltd.
    Inventors: Zhaolei Wu, Guosheng Wu
  • Patent number: 8848835
    Abstract: An interpolation circuit includes: a generation circuit configured to generate interpolated data based on a plurality of pieces of input data in time sequence; a first analog digital converter configured to convert first interpolated data at a data point of the interpolated data into first digital data; and a second analog digital converter configured to convert second interpolated data at a change point into second digital data of the interpolated data, a second number of quantization bits of the second analog digital converter being smaller than a first number of quantization bits of the first analog digital converter.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: September 30, 2014
    Assignee: Fujitsu Limited
    Inventor: Takayuki Shibasaki
  • Publication number: 20140286469
    Abstract: A burst mode CDR detects an edge from a data signal superimposed with a clock, and generates a recovered clock by means of a voltage controlled oscillator whose oscillation operation is reset based on a timing when the edge is detected. A phase adjustment unit adjusts the phase of a data signal so as to coincide with the phase of a recovered clock. A PLL-based CDR adjusts the oscillation frequency of the recovered clock by means of the voltage controlled oscillator, based on a phase difference between a data signal whose phase has been adjusted by the phase adjustment unit and a feedback clock from the voltage controlled oscillator. A determination unit determines the value of the data signal at a timing when the signal level of the recovered clock transitions.
    Type: Application
    Filed: December 20, 2013
    Publication date: September 25, 2014
    Applicant: FUJITSU LIMITED
    Inventors: Takayuki SHIBASAKI, Hirotaka TAMURA
  • Patent number: 8842794
    Abstract: A method of communication to a semiconductor device includes: transmitting a sampling clock signal from a first semiconductor device to a second semiconductor device; transmitting a training signal from the first semiconductor device to the second semiconductor device while transmitting of the sampling clock signal, the training signal comprising plural test patterns sent sequentially to the second semiconductor device, phases of at least some of the test patterns being adjusted to be different from each other during transmitting of the training signal; receiving first information from the second semiconductor device over a first signal line, the first signal line separate from a data bus connected between the first semiconductor device and the second semiconductor device; and transmitting a data signal over the data bus while transmitting the sampling clock signal, the data signal sent at a timing with respect to the sampling clock signal responsive to the received first information.
    Type: Grant
    Filed: December 14, 2012
    Date of Patent: September 23, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Seung-Jun Bae, Seong-Jin Jang, Beom-Sig Cho
  • Patent number: 8842714
    Abstract: An electronic device may contain clock circuits, transmitters, and other circuits that serve as sources of noise signals. The noise signals may be characterized by a noise spectrum. The noise spectrum produced by a noise source can be adjusted by adjusting spread spectrum clock circuitry in a clock circuit, by adjusting data scrambling circuitry in a transmitter circuit, or by making other dynamic adjustments to the circuitry of the electronic device. During operation of the electronic device, sensitive circuitry in the device such as wireless receiver circuitry may be adversely affected by the presence of noise from a noise source in the device. Based on information such as which receiver bands and/or channels are being actively received and target sensitivity levels for the receiver circuitry, control circuitry within the electronic device can determine in real time how to minimize interference between the noise source and the wireless receiver circuitry.
    Type: Grant
    Filed: March 9, 2012
    Date of Patent: September 23, 2014
    Assignee: Apple Inc.
    Inventors: Moon Jung Kim, Geertjan Joordens, Paolo Sacchetto, Wonjae Choi, Altan N. Yazar, Jaydeep V. Ranade
  • Patent number: 8836387
    Abstract: Methods and systems for compensating reducing jitter produced by a phase-locked loop are disclosed. For example, in a particular embodiment, a phase-locked loop device for reducing jitter may include a voltage-control oscillator (VCO) signal configured to produce a VCO signal, phase-detection circuitry configured to compare an input signal and the VCO signal to produce a phase error signal, and slew-rate limiting circuitry configured to receive the phase error signal and apply a slew-rate limit process on the phase error signal to produce a modified error signal.
    Type: Grant
    Filed: January 4, 2011
    Date of Patent: September 16, 2014
    Assignee: Marvell International Ltd.
    Inventors: Jin Xie, Bin Ni, Mats Oberg
  • Patent number: 8829958
    Abstract: An integrated circuit (“IC”) may include clock and data recovery (“CDR”) circuitry for recovering data information from an input serial data signal. The CDR circuitry may include a reference clock loop and a data loop. A retimed (recovered) data signal output by the CDR circuitry is monitored by other control circuitry on the IC for a communication change request contained in that signal. Responsive to such a request, the control circuitry can change an operating parameter of the CDR circuitry (e.g., a frequency division factor used in either of the above-mentioned loops). This can help the IC support communication protocols that employ auto-speed negotiation.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: September 9, 2014
    Assignee: Altera Corporation
    Inventors: Kazi Asaduzzaman, Tim Tri Hoang, Tin H. Lai, Shou-Po Shih, Sergey Shumarayev