Phase Locking Patents (Class 375/373)
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Patent number: 8638884Abstract: The data processing unit (15) for a receiver of signals carrying information (1) includes a clock and data recovery circuit (16) on the basis of a data signal (DOUT), and a processor circuit (17) connected to the clock and data recovery circuit. The clock and data recovery circuit is clocked by a local clock signal (CLK) and includes a numerical phase lock loop, in which a numerically controlled oscillator (25) is arranged. This numerically controlled oscillator generates an in-phase pulse signal (IP) and a quadrature pulse signal (QP) at output. The frequency and phase of the pulse signals IP and QP are adapted on the basis of the received data signal (DOUT). The processor circuit is arranged to calculate over time the mean and variance of the numerical input signal (NCOIN) of the numerically controlled oscillator (25), so as to determine the coherence of the data signal if the calculated mean and variance are below a predefined coherence threshold.Type: GrantFiled: October 19, 2011Date of Patent: January 28, 2014Assignee: The Swatch Group Research and Development LtdInventor: Arnaud Casagrande
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Patent number: 8634512Abstract: A two point modulation digital phase locked loop circuit is disclosed. The circuit includes a sampling clock input that is switchable between a plurality of frequencies. The circuit also includes a sigma-delta modulator in a feedback path that receives low-pass modulation data. The circuit also includes a voltage-mode digital-to-analog converter (VDAC) that receives high-pass modulation data. The circuit also includes an analog voltage controlled oscillator coupled to the feedback path and the output of the VDAC. The circuit also includes a phase-to-digital converter (PDC) coupled to the feedback path, the sampling clock and a loop filter.Type: GrantFiled: February 8, 2011Date of Patent: January 21, 2014Assignee: QUALCOMM IncorporatedInventors: Lai Kan Leung, Chiewcharn Narathong
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Patent number: 8634503Abstract: A clock-data recovery system and method promotes fast adjustment to large phase changes in the incoming data signal. The system can include phase alignment circuitry, clock generator circuitry, time-to-digital converter circuitry, and sampling circuitry. The phase alignment circuitry uses the incoming data signal and a feedback clock signal to generate an output clock signal. The clock generator circuitry uses the output clock signal to generate base phase clock signals of different phases or polarities. The time-to-digital converter circuitry uses the base phase clock signals and the incoming data signal to generate the feedback clock signal. The time-to-digital converter circuitry bases the feedback clock signal on the base phase clock signal that is aligned more closely in phase with the incoming data signal than the other base phase clock signals. The sampling circuitry re-times or recovers the data signal using one or more of the base phase clock signals.Type: GrantFiled: March 31, 2011Date of Patent: January 21, 2014Inventors: Brian J. Misek, Robert K. Barnes, Peter J. Meier
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Patent number: 8625728Abstract: A communication system including a phase-locked loop, a signal division controller, a divider, and a transmitter. The phase-locked loop is configured to generate an output signal in response to a common reference clock signal. The output signal is in phase lock with the common reference clock signal. The signal division controller is configured to receive a select signal, select an edge of a rising edge of the output signal and a falling edge of the output signal in response to the select signal, and generate a divider reset signal in response to the selected edge. The divider is configured to generate a communication clock signal by performing frequency division of the output signal. The divider reset signal controls a start time of the frequency division. The transmitter is configured to operate in response to the communication clock signal.Type: GrantFiled: April 30, 2012Date of Patent: January 7, 2014Assignee: Marvell International Ltd.Inventor: Pierte Roo
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Patent number: 8625730Abstract: In a phase locked loop, frequency-divided clocks each of which is given a phase difference of at least one cycle of a feedback clock are inputted to a first phase comparator and a second phase comparator, respectively, which are made to perform phase comparison with a reference clock. Then, outputs of the first and second phase comparators are weighted by a result of the phase comparison of a receive signal and the feedback clock, and phase adjustment of the feedback clock is phase adjusted using the weighted outputs. Thereby, it is possible to lower a frequency of the reference clock and consequently to suppress power consumption.Type: GrantFiled: July 12, 2011Date of Patent: January 7, 2014Assignee: Hitachi, Ltd.Inventors: Tatsunori Usugi, Daisuke Hamano
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Patent number: 8619755Abstract: Embodiments of a dual-master mode Ethernet node are provided herein. The dual-master mode Ethernet node includes a first multiplexer configured to select between a local oscillator signal and a primary reference source (PRS) signal to provide a reference clock signal, a digital phase-locked loop (DPLL) configured to generate a master clock signal based on the reference clock signal, a phase rotator configured to rotate a phase of the master clock signal based on a frequency error between the master clock signal and an extracted clock signal to generate a slave clock signal, and a second multiplexer configured to select between the master clock signal and the slave clock signal to provide a transmit clock signal. The dual-master mode Ethernet node can dynamically generate the transmit clock based on either the extracted clock or the PRS without re-performing the auto-negotiation process.Type: GrantFiled: January 3, 2011Date of Patent: December 31, 2013Assignee: Broadcom CorporationInventors: Peiqing Wang, Linghsiao Wang
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Patent number: 8619839Abstract: An interface module (4) for a unit (1, 2) which is designed to transmit and/or amplify essential communication signals inside an antenna distribution system (29) is specified, said module comprising a first analog interface (6) for forwarding and receiving essential communication signals from mobile terminals (32), a second interface (7) for forwarding and receiving essential communication signals from the antenna distribution system (29), at least one signal path (9, 10) for forwarding the received communication signals between the two interfaces (6, 7), and a controllable digital unit (11) which incorporates the signal path (9, 10) and has means for digitizing incoming communication signals and for subjecting outgoing communication signals to analog conversion. In this case, the digital unit (11) is designed to identify essential communication signals in the digitized communication signals, to mask the remaining signals and to forward the essential communication signals.Type: GrantFiled: April 26, 2011Date of Patent: December 31, 2013Assignee: Andrew Wireless Systems GmbHInventors: Oliver Braz, Jorg Stefanik, Jaroslav Hoffmann
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Patent number: 8619934Abstract: A clock data recovery system is described. It includes a high pass filter for transmitting a filtered data signal in response to receiving an input data signal; an adder for summing the filtered data signal with a feedback signal, wherein the adder produces a summed input signal; a plurality of clocked data comparators for receiving the summed input signal, wherein the clocked data comparators determine an input data bit value; a plurality of clocked error comparators for receiving an error signal associated with clock recovery; an equalization and adaptation logic for selecting an error sample such that a phase associated with the error sample is locked at a second post cursor; and a phase mixer for transmitting a delay in response to receiving the phase and the delay is transmitted to the clocked-data comparators and the clocked-error comparators.Type: GrantFiled: August 11, 2010Date of Patent: December 31, 2013Assignee: Texas Instruments IncorporatedInventors: Hae-Chang Lee, Arnold Robert Feldman, Andrew Joy
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Patent number: 8619938Abstract: A clock generation device provided for a transmitter is provided and comprises a clock generator, a calculator and a first phase locked loop (PLL) circuit. The clock generator generates a first clock signal. The calculator calculates a frequency difference between the first and second clock signals. The first PLL circuit generates an output clock signal according to a first reference clock signal related to the first clock signal, and a frequency of the output clock signal is changed according to the frequency difference. The transmitter transmits data according to the output clock signal.Type: GrantFiled: December 5, 2008Date of Patent: December 31, 2013Assignee: Mediatek Inc.Inventors: Kuan-Hua Chao, Chuan Liu, Tse-Hsiang Hsu
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Patent number: 8619924Abstract: 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: GrantFiled: February 23, 2010Date of Patent: December 31, 2013Assignee: Atmel CorporationInventors: Ulrich Grosskinsky, Werner Blatz
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Patent number: 8619937Abstract: An integrated CMOS clock generator with a self-biased phase locked loop circuit comprises a phase-frequency detector with a reference signal input, a feedback signal input and an output. A first charge pump of the clock generator has an input connected to the output of the phase-frequency detector and an output that supplies a control voltage. A loop capacitor is connected to the output of the first charge pump. The clock generator further has a second charge pump with an input connected to the output of the phase-frequency detector and an output. In particular, the clock generator has two oscillator blocks.Type: GrantFiled: December 16, 2005Date of Patent: December 31, 2013Assignee: Texas Instruments Deutschland GmbHInventor: Joern Naujokat
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Patent number: 8611371Abstract: A device (D2) is dedicated to the reconstruction of clock signals, for example within communication equipment (EQ2) of an IP network. This device (D2) comprises i) a phase-locked loop (BY) having a cut-off frequency dependent, on the one hand, on a configuration value making it possible to reconstruct clock signals according to a chosen clock frequency, and on the other hand, a chosen sampling frequency, and ii) control means (MC2) responsible for forcing the phase-locked loop (BV) to present a variable cut-off frequency according to a received operating mode indication.Type: GrantFiled: February 5, 2008Date of Patent: December 17, 2013Assignee: Thomson LicensingInventors: Thierry Tapie, Serge Defrance, Luis Montalvo
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Patent number: 8605848Abstract: An arrangement for synchronizing a transmission time of a digital data stream in individual high-frequency transmitters of a common-wave network operating according to an ATSC standard and transmitting identical data at an identical frequency. The stream generated in a master station is supplied to the transmitters as a periodic succession of data frames, and a setpoint transmission time is calculated in the transmitters from a synchronizing time stamp inserted into the data frames within the master station and from a time reference used in the master station and transmitters, while the transmission of the frames by the transmitter is determined by a system clock in the transmitters. The setpoint transmission time is compared with the actual transmission time determined by the clock, and the clock frequency is regulated by a regulating circuit so that the actual transmission time determined by the clock corresponds with the calculated setpoint transmission time.Type: GrantFiled: March 9, 2007Date of Patent: December 10, 2013Assignee: Rohde & Schwarz GmbH & Co. KGInventors: Cornelius Heinemann, Wolfgang Boehm
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Patent number: 8605846Abstract: 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: GrantFiled: December 17, 2010Date of Patent: December 10, 2013Assignee: Maxim Integrated Products, Inc.Inventors: Matthew Felder, Mark Summers
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Patent number: 8605847Abstract: In described embodiments, a transceiver includes a clock and data recovery module (CDR) with an eye monitor and a cycle slip monitor. The cycle slip detector monitors a CDR lock condition, which might be through detection of slips in sampling and/or transition timing detection. The cycle slip detector provides a check point to sense system divergence, allowing for a mechanism to recover CDR lock. In addition, when the CDR is out-of-lock, the various parameters that are adaptively set (e.g., equalizer parameters) might be invalid during system divergence. Consequently, these parameters might be declared invalid by the system and not used.Type: GrantFiled: March 9, 2011Date of Patent: December 10, 2013Assignee: LSI CorporationInventors: Mohammad Mobin, Mark Trafford, Ye Liu, Vladimir Sindalovsky, Amaresh Malipatil
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Patent number: 8599985Abstract: In accordance with an embodiment of the present disclosure a phase-locked loop comprises a voltage controlled oscillator (VCO) configured to generate an output signal based on an input reference signal. The phase-locked loop further comprises a first charge pump communicatively coupled to a control input of the VCO and configured to generate, for a duration of time following occurrence of an event, a first control signal. The first control signal is independent of the output signal and is for causing the output signal to have a first frequency based on a second frequency of the input reference signal. The phase-locked loop further comprises a second charge pump communicatively coupled to the control input of the VCO. The second charge pump is configured to generate, after the duration of time, a second control signal.Type: GrantFiled: April 5, 2011Date of Patent: December 3, 2013Assignee: Intel IP CorporationInventor: Rizwan Ahmed
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Patent number: 8599984Abstract: A delay locked loop operates over a wide range of frequencies and has high accuracy, small silicon area usage, low power consumption and a short lock time. The DLL combines an analog domain and a digital domain. The digital domain is responsible for initial lock and operational point stability and is frozen after the lock is reached. The analog domain is responsible for normal operation after lock is reached and provides high accuracy using smaller silicon area and low power.Type: GrantFiled: March 26, 2013Date of Patent: December 3, 2013Assignee: MOSAID Technologies IncorporatedInventors: Peter Vlasenko, Dieter Haerle
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Patent number: 8594214Abstract: Disclosed is an input module of a programmable logic controller (PLC) capable of counting coefficient values of multiple channels. An input module of a PLC includes a plurality of detection units, a decision unit and a control unit. The plurality of detection units receives a pulse signal corresponding to each channel, applied from a load having a plurality of channels, detects rising and falling edges of the pulse signal, and transmits an output signal that is the detected result. The decision unit receives a plurality of output signals respectively transmitted from the plurality of detection units, detects edges of the plurality of channels, and transmits a detection signal that is the detected result. The control unit identifies the presence of occurrence of an interrupt using the detection signal transmitted from the decision unit and performs a counting process using the applied pulse signal when the interrupt occurs.Type: GrantFiled: April 4, 2011Date of Patent: November 26, 2013Assignee: LSIS Co., Ltd.Inventor: Sang Back Lee
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Patent number: 8588281Abstract: A transceiver comprises a transmitter that converts a plurality of data components into serial data in response to a first clock signal and transmits the serial data, and a receiver that receives the serial data and converts the serial data into the plurality of data components in response to a second clock signal generated from the serial data. The transmitter adds at least one dummy bit to the serial data at predetermined intervals. The at least one dummy bit includes information regarding a data type of the plurality of data components.Type: GrantFiled: February 7, 2011Date of Patent: November 19, 2013Assignee: Samsung Electronics Co., Ltd.Inventors: Woon-taek Oh, Jae-youl Lee, Jin-ho Kim, Tae-jin Kim, Ju-hwan Yi, Jong-shin Shin
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Patent number: 8588355Abstract: A timing recovery controller capable of performing timing recovery for a data sequence at twice a symbol rate includes a sampler, a timing base device, a timing error detector and a timing lock detector. The timing error detector includes a first delay unit and a second delay unit, for delaying a data sequence to output a first delay data sequence and a second delay data sequence, respectively, and a timing error calculating module, for generating a timing error value, to adjust a time base. The timing lock detector includes a third delay unit, for delaying the data sequence to output a third delay data sequence, and a timing lock determination module, for generating a timing lock determination result.Type: GrantFiled: August 6, 2010Date of Patent: November 19, 2013Assignee: NOVATEK Microelectronics Corp.Inventor: Kung-Piao Huang
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Patent number: 8588356Abstract: A method for receiving a signal having a succession of symbols, transmitted by a digital modulation, each symbol transmitted having a phase and an amplitude belonging to a set of values in finite number, the method includes evaluating a phase error (PHE) on a received symbol (S), resulting from a signal transmission noise, correcting the phase of the received symbol according to the phase error evaluated, demodulating the symbol corrected in phase, and modeling the transmission noise by a Gaussian component not correlated with the signal received and defined by a power and an interference component defined by an amplitude and which phase is substantially uniformly distributed, the phase error of the received symbol evaluated on the basis of the power of Gaussian component and the amplitude of the interference component.Type: GrantFiled: October 21, 2010Date of Patent: November 19, 2013Assignee: STMicroelectronics (Grenoble 2) SASInventor: Jacques Meyer
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Patent number: 8588329Abstract: A phase-locked loop having: an oscillator for forming an oscillating output signal; a frequency divider connected to receive the output of the oscillator and frequency divide it by a value dependent on a division control signal; and a phase comparator for comparing the phase of the divided signal and a reference signal to generate a control signal, the operation of the oscillator being dependent on the control signal; the output data to form a divided signal a division ratio controller configured to, when clocked by an input signal, generate a series of output data for forming the division control signal; the phase-locked loop having: a first mode of operation in which the frequency divider is operable to frequency divide the output of the oscillator by a value dependent on the output of the division ratio controller; and a second mode of operation in which the frequency divider is not operable to frequency divide the output of the oscillator by a value dependent on the output of the division ratio controllerType: GrantFiled: March 13, 2009Date of Patent: November 19, 2013Assignee: Cambridge Silicon Radio LimitedInventors: Pasquale Lamanna, Nicolas Somin
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Patent number: 8588358Abstract: 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. A delay locked loop (DLL) is configured to receive the clock signal from the LCVCO and generate multiple clock phases. A charge pump is configured to control the LCVCO. A phase detector is configured to receive a data input and the multiple clock phases from the DLL, and to control the first charge pump in order to align a data edge of the data input and the multiple clock phases.Type: GrantFiled: March 11, 2011Date of Patent: November 19, 2013Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.Inventors: Chan-Hong Chern, Chih-Chang Lin, Ming-Chieh Huang, Fu-Lung Hsueh
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Patent number: 8582710Abstract: Embodiments allow for the use of the SS modulation technique (and thus for significant reduction of EMI due to clock transmission) in scenarios involving tight synchronization requirements between two devices. In particular, embodiments can be used in high-speed communication networks (e.g., high-speed Ethernet) where a clock signal embedded in the data stream at the transmitter and recovered from the data stream at the receiver is the only source for synchronization between the transmitter and the receiver (i.e., no other synchronization channel available). Embodiments are also especially useful in communication systems utilizing echo cancellers.Type: GrantFiled: March 31, 2011Date of Patent: November 12, 2013Assignee: Broadcom CorporationInventors: Neven Pischl, Joseph Cordaro, Yongbum Kim
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Patent number: 8582690Abstract: An apparatus for determining signal power comprise an oscillating circuit and a determining circuit. The oscillating circuit generates an oscillating signal. When a to-be-detected signal has signal power greater than a threshold, the oscillating signal has a first frequency; when the signal power is smaller than the threshold, the oscillating signal has a second frequency. The determining circuit determines whether the oscillating signal has either the first frequency or the second frequency, and generates a determination result accordingly.Type: GrantFiled: December 21, 2010Date of Patent: November 12, 2013Assignee: MStar Semiconductor, Inc.Inventors: Ming Yu Hsieh, Shih-Chieh Yen
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Patent number: 8582708Abstract: A clock and data recovery circuit includes a multiphase clock generator circuit which generates a multiphase clock having a plurality of clocks, a sampling circuit which samples a received data signal transferring serial data in synchronism with each of the plurality of clocks, and generates a plurality of data signals, a data recovery unit which generates a selection signal indicating a data signal having an appropriate phase among the plurality of data signals, and a storage unit which stores the selection signal. The data recovery unit selects one of the plurality of data signals, based on the selection signal read from the storage unit, and a clock corresponding to the selected data signal.Type: GrantFiled: January 5, 2012Date of Patent: November 12, 2013Assignee: Panasonic CorporationInventors: Michiyo Yamamoto, Kenji Murata, Kazuya Hatooka
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Transmitting apparatus, receiving apparatus, transmitting/receiving system, and image display system
Patent number: 8582628Abstract: A data reception unit 21 of a reception device 20n receives calibration data to detect a data reception state or a clock reception state in the reception device 20n from a data transmission unit 11 of a transmission device 10. A decoder unit 24 causes a transmission unit 26 to send out calibration sample data that a sampler unit 23 obtained by sampling calibration data to the transmission device 10. A control unit 15 of the transmission device 10 detects a data reception state or a clock reception state in the reception device 20n based on calibration sample data received from the reception device 20n and controls the data transmission unit 11 and a clock transmission unit 12 based on the detection result.Type: GrantFiled: October 20, 2010Date of Patent: November 12, 2013Assignee: Thine Electronics, Inc.Inventors: Seiichi Ozawa, Hironobu Akita -
Publication number: 20130294492Abstract: A system may include a clock and data recovery circuit that includes one or more analog components. The system may also include a digital control circuit configured to control the clock and data recovery circuit. The digital control circuit and the clock and data recovery circuit may be formed on a single substrate.Type: ApplicationFiled: May 4, 2012Publication date: November 7, 2013Applicant: FINISAR CORPORATIONInventor: Jason Y. MIAO
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Patent number: 8576970Abstract: A PLL circuit (1a, 1b) for generating a pixel-clock signal based on a hsync signal. The PLL circuit comprises a phase-frequency detector arranged to receive the hsync signal and a frequency divided pixel-clock signal, and generate up and down signals based on the hsync signal and the frequency-divided pixel-clock signal. A charge pump (20) is arranged to generate an output signal based on the up and down signals and a loop filter (30) is arranged to generate a frequency-control signal based on the output signal of the charge pump (20). Furthermore, a VCO (40a, 40b) is arranged to generate an oscillating signal and adjust the frequency of the oscillating signal in response to the frequency-control signal. The VCO (40a, 40b) is adapted to have a tuning range with a center frequency which is larger than or equal to 4 GHz.Type: GrantFiled: September 9, 2009Date of Patent: November 5, 2013Assignee: CSR Technology Inc.Inventors: Graham R. Leach, Gordon A. Wilson, Rolf Sundblad
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Patent number: 8571158Abstract: A method and a data transceiving system for generating a reference clock signal are provided. The data transceiving system comprises a voltage controlled oscillator, a phase lock loop (PLL) unit, and a data receiver. The voltage controlled oscillator is used to generate a reference clock signal. The PLL unit is used to increase a clock frequency of the reference clock signal to generate a PLL clock signal. The data receiver is used to compare the PLL clock signal with a clock signal of an input data stream, so as to output a voltage adjusting signal to the voltage controlled oscillator. The voltage controlled oscillator adjusts the clock frequency of the reference clock signal to be generated according to the reference clock signal, so as to lock the clock frequency of the PLL clock signal to a base frequency of the clock signal of the input data stream.Type: GrantFiled: August 17, 2010Date of Patent: October 29, 2013Assignee: Phison Electronics Corp.Inventors: An-Chung Chen, Wen-Lung Cheng, Wei-Yung Chen
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Patent number: 8565362Abstract: A clock recovery apparatus includes a mask generator configured to generate a plurality of time masks using a multi-phase clock signal and a clock recovery unit configured to select one of the time masks to recover a clock from a data stream.Type: GrantFiled: December 17, 2010Date of Patent: October 22, 2013Assignee: Dongbu HiTek Co., Ltd.Inventor: Sang Seob Kim
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Patent number: 8564347Abstract: Embodiments include implementing a phase detector for a delay-locked loop (DLL) circuit that is operable to detect substantially 270 degree and substantially 540 degree phase differences between two clock signals. In an embodiment, a DLL circuit comprises a delay line receiving a system clock signal and generating phase shifted clock signals, a phase detector receiving the system clock signal and phase shifted clock signal, and configured to generate corresponding up and down signals upon detection of a phase shift of substantially 270 degrees between the system clock signal and the phase shifted clock signal, a charge pump coupled to the phase detector, and configured to receive the up and down signals and generate a control signal responsive to thereto, and a regulator circuit to receive the control signal from the charge pump and generate a voltage control signal to the delay chain to control delay of the system clock signal.Type: GrantFiled: September 7, 2012Date of Patent: October 22, 2013Assignee: Advanced Micro Devices, Inc.Inventors: Min Xu, Ming-Ju E. Lee
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Patent number: 8559582Abstract: A circuit includes a phase detection circuit, a phase adjustment circuit, and a sampler circuit. The phase detection circuit compares a phase of a first periodic signal to a phase of a second periodic signal to generate a control signal. The phase adjustment circuit causes the phase of the second periodic signal and a phase of a third periodic signal to vary based on a variation in the control signal. The sampler circuit samples a data signal to generate a sampled data signal in response to the third periodic signal. The circuit varies a frequency of the third periodic signal to correspond to changes in a data rate of the data signal between at least three different data rates that are based on at least three data transmission protocols.Type: GrantFiled: September 13, 2010Date of Patent: October 15, 2013Assignee: Altera CorporationInventor: Tim Tri Hoang
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Patent number: 8558592Abstract: A circuit containing a pair of charge pumps and an active filter receives outputs of a phase frequency detector used in a phase locked loop. The charge pump is implemented using switches and resistors to reduce performance variations due to component mismatches. The loop filter includes a resistor and a capacitor coupled in series, the resistor and the capacitor determining a zero of the transfer function of the loop filter. The charge pump circuit simultaneously injects a first current pulse at a first node of the loop filter and a second current pulse at a second node formed by a junction of the resistor and the capacitor. The polarity of the first current pulse is the opposite of the polarity of the second current pulse. Multiplication of the capacitance of the capacitor is thereby achieved, enabling implementation of the loop filter in integrated circuit form.Type: GrantFiled: February 3, 2011Date of Patent: October 15, 2013Assignee: Texas Instruments IncorporatedInventors: Samala Sreekiran, Ramesh Chettuvetty
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Patent number: 8553827Abstract: A Phase-Locked Loop (PLL) includes a Phase-to-Digital Converter (PDC), a programmable digital loop filter, a Digitally-Controlled Oscillator (DCO), and a loop divider. Within the PDC, phase information is converted into a stream of digital values by a charge pump and an Analog-to-Digital Converter (ADC). The stream of digital values is supplied to the digital loop filter which in turn supplies digital tuning words to the DCO. A number of types of ADCs can be used for the ADC including a continuous-time delta-sigma oversampling Digital ADC and a Successive Approximation ADC. The voltage signal on the charge pump output is a small amplitude midrange voltage signal. The small voltage amplitude of the signal leads to numerous advantages including improved charge pump linearity, reduced charge pump noise, and lower supply voltage operation of the overall PLL.Type: GrantFiled: October 20, 2009Date of Patent: October 8, 2013Assignee: Qualcomm IncorporatedInventor: Gang Zhang
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Patent number: 8548405Abstract: A method of controlling the phases of RF output signals from a number of radio transmitters. A given radio has at least one synthesizer as a source of its RF output signal, and the synthesizer produces an output the phase offset of which relative to a reference signal is controlled by a phase offset command. A path from an antenna port of the radio obtains a fed back RF output signal and a phase difference between the reference signal and the fed back RF output signal is measured. A value of a zero degree phase offset command for the synthesizer is determined such that the phase difference between the reference signal and the fed back RF signal is nominally zero, and the value is stored. A phase offset command for providing a desired phase offset for the RF output signal is then determined based the stored value of the zero degree phase offset command.Type: GrantFiled: April 25, 2012Date of Patent: October 1, 2013Assignee: BAE Systems Information and Electronic Systems Integration Inc.Inventor: Michael S. Vogas
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Patent number: 8543068Abstract: A transceiver node includes a pulse coupled oscillator in an integrated circuit, which can synchronize with other nodes to generate a global clock subsequently used to facilitate synchronous communications between individual nodes. Known potential uses include a low power sensor node radio for an ad-hoc network for military applications and medical applications such as ingestible and implantable radios, self powered radios, and medical monitoring systems such as cardiac and neural monitoring patches.Type: GrantFiled: August 4, 2008Date of Patent: September 24, 2013Assignee: Cornell UniversityInventors: Xiao Y. Wang, Alyssa B. Apsel
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Patent number: 8537953Abstract: A clock-data recovery (CDR) that employs a time-interleaved scheme is disclosed. The circuit comprises: a time-interleaved sampler/phase-detector circuit for receiving an input voltage signal and a plurality of clock signals and outputting N-bit data and N phase signals, wherein N is an integer greater than 1; a control circuit, coupled to the time-interleaved sampler/phase-detector circuit, for receiving the N phase signals and converting the N phase signals into a control signal; and a controlled oscillator, coupled to the control circuit, for generating the plurality of clock signals under the control of the control signal. The CDR is used to relax circuit speed requirement by time-interleaving phase detection by using a multi-phase lower speed circuit.Type: GrantFiled: September 13, 2008Date of Patent: September 17, 2013Assignee: Realtek Semiconductor Corp.Inventor: Chia-Liang Lin
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Patent number: 8537945Abstract: An apparatus includes Radio Frequency (RF) circuitry and baseband circuitry. The RF circuitry is configured to receive strobe messages that are based on a system clock over a digital interface, and to communicate synchronously with the system clock based on the received strobe messages in accordance with a Radio Access Technology (RAT) that is selected from among multiple different RATs. The baseband circuitry is configured to generate the strobe messages, to delay the strobe messages by a delay that depends on the selected RAT, and to send the delayed strobe messages to the RF circuitry over the digital interface.Type: GrantFiled: November 21, 2010Date of Patent: September 17, 2013Assignee: Marvell International Ltd.Inventors: Daniel Ben-Ari, Avner Epstein
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Patent number: 8537952Abstract: A fractional-N PLL uses separate charge pumps under the control of separate frequency and phase detectors. Phase jitter from an N divider is linearized by the use of a circuit that generates pulses from the output of the N divider. After frequency lock, the frequency detector turns off the frequency charge pump. After phase lock, activity in the phase detector down charge pump is minimized, reducing the overall noise produced by respective phase and frequency detector charge pumps.Type: GrantFiled: March 7, 2008Date of Patent: September 17, 2013Assignee: Marvell International Ltd.Inventor: Himanshu Arora
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Patent number: 8537957Abstract: A clock synchronizer for generating a local clock signal synchronized to a received clock signal. The clock synchronizer incorporates a reference oscillator providing a reference signal, and a synthesizer circuit arranged to synthesize a local clock signal from the reference signal. The synthesizer circuit comprises a phase-locked-loop circuit, including a phase detector receiving the reference signal, and a controllable divider arranged in a feedback path from a controlled oscillator to the phase detector, the divider being controllable to set a frequency division value N along the path to determine a ratio of the local clock frequency to the reference frequency. The clock synchronizer also incorporates a clock comparison circuit adapted to generate a digital signal indicative of an asynchronism between the local and received clock signals. A control link is arranged to link the clock comparison circuit to the divider.Type: GrantFiled: May 23, 2011Date of Patent: September 17, 2013Assignee: Wolfson Microelectronics plcInventor: Paul Lesso
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Patent number: 8537935Abstract: A change-point detection circuit 16 extracts a clock signal from serial data, input data. A variable delay circuit provides a delay in accordance with a delay control signal to a reference signal having a predetermined frequency, so that the phase of the reference signal is shifted on the basis of an initial delay. An input latch circuit latches internal serial data by using an output signal of the variable delay circuit as a strobe signal. A phase comparator matches the frequencies of the clock signal and the strobe signal with each other, and generates phase difference data in accordance with a phase difference between the two signals. A loop filter integrates the phase difference data generated by the phase comparator and outputs it as the delay control signal. The phase shift amount acquisition unit acquires a phase shift amount based on the delay control signal, the phase shift amount being based on the initial delay provided to the reference signal by the variable delay circuit.Type: GrantFiled: March 18, 2008Date of Patent: September 17, 2013Assignee: Advantest CorporationInventors: Daisuke Watanabe, Toshiyuki Okayasu
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Patent number: 8537956Abstract: A demultiplexer circuit separates input data having different data rates into output data. A phase-locked loop circuit generates first clock signals having average frequencies that are based on a frequency of a second clock signal times a fractional, non-integer number. A serializer circuit serializes a set of the output data to generate serial data signals in response to one of the first clock signals generated by the phase-locked loop circuit.Type: GrantFiled: November 24, 2010Date of Patent: September 17, 2013Assignee: Altera CorporationInventors: Tien Duc Pham, Leon Zheng, Sergey Shumarayev, Zhi Y. Wong, Paul B. Ekas
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Patent number: 8532243Abstract: A technique that is readily implemented in monolithic integrated circuits includes a method including generating an output clock signal during a presence of a reference clock signal based, at least in part, on a digital control value indicating a phase difference between a feedback signal of a PLL and a reference clock signal. The method includes generating the output clock signal during an absence of the reference clock signal and based, at least in part, on an average digital control word indicating an average value of a number of samples of the digital control value during the presence of the reference clock signal, the number of samples preceding the absence of the reference clock signal by a delay period. The number of samples is selected from a plurality of numbers of samples and the delay period is selected from a plurality of delay periods.Type: GrantFiled: February 12, 2007Date of Patent: September 10, 2013Assignee: Silicon Laboratories Inc.Inventors: Srisai R. Seethamraju, Jerrell P. Hein, Kenneth Kin Wai Wong, Qicheng Yu
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Patent number: 8532163Abstract: A transceiver system is disclosed that includes a plurality of transceiver chips. Each transceiver chip includes one or more SERDES cores. Each SERDES core includes one or more SERDES lanes. Each SERDES lane includes a receive channel and a transmit channel. The transmit channel of each SERDES lane is phase-locked with a corresponding receive channel. The transceiver system has the capability of phase-locking a transmit clock signal phase of a transmitting component with a receive clock signal phase of a receiving component that is a part of a different SERDES lane, a different SERDES core, a different substrate, or even a different board. Each SERDES core receives and transmits data to and from external components connected to the SERDES core, such as hard disk drives. A method of transferring data from a first external component coupled to a receive channel to a second external component coupled to a transmit channel is also disclosed.Type: GrantFiled: February 6, 2012Date of Patent: September 10, 2013Assignee: Broadcom CorporationInventors: Abbas Amirichimeh, Howard Baumer, John Louie, Vasudevan Parthasarathy, Linda Ying
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Patent number: 8531214Abstract: Spread spectrum generators and methods are disclosed. In one implementation, a spread spectrum clock generator includes a phase locked loop generating an output clock according to a first clock and a second clock; a delay line coupled between the first clock and the phase locked loop; a modulation unit providing a modulation signal to control the delay line thereby modulating phase of the first clock, such that frequency of the output clock generated by the phase locked loop varies periodically; a scaling unit scaling the modulation signal from the modulation unit according to a scaling ratio, and outputting to the delay line; and a calibration unit generating an output signal for controlling the scaling ratio.Type: GrantFiled: January 18, 2013Date of Patent: September 10, 2013Assignee: MediaTek Inc.Inventors: Shang-Ping Chen, Ping-Ying Wang
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Patent number: 8520793Abstract: A phase detector includes a first sampling unit, a sampling module and a phase determining module. The first sampling unit is arranged for sampling a first data input signal to generate a first data signal according to a first clock signal. The sampling module includes a second sampling unit and a third sampling unit. The second sampling unit is arranged for sampling a second data input signal to generate a second data signal according to a second clock signal. The third sampling unit is arranged for sampling the second data signal to generate a third data signal according to the first clock signal. The phase determining module is arranged for generating a phase detecting result according to the first data signal and the third data signal.Type: GrantFiled: April 20, 2011Date of Patent: August 27, 2013Assignee: Faraday Technology Corp.Inventors: Chun-Cheng Lin, Ming-Shih Yu
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Patent number: 8520725Abstract: A data equalizing circuit includes an equalizer configured to control a gain of data according to a value of a control code and output a controller gain; and a detection unit configured to divide n cycles of the data into N periods, count data transition frequencies for n/N periods while changing the value of the control code, calculate dispersion values of data transition frequencies for 1/N periods of the data from the data transition frequencies for the n/N periods, and finally output the value of the control code corresponding to a largest dispersion value, wherein n is equal to or greater than 2 and is set such that boundaries of the respective n/N periods of the data have different positions in the 1 UI data.Type: GrantFiled: February 28, 2012Date of Patent: August 27, 2013Assignee: SK Hynix Inc.Inventors: Chun Seok Jeong, Jae Jin Lee, Chang Sik Yoo, Jang Woo Lee, Seok Joon Kang
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Patent number: 8514922Abstract: This invention relates to an apparatus and a method for controlling a filter coefficient. The filter coefficient control apparatus controls a coefficient of a filter of a phase recovering apparatus, and comprises a phase offset obtaining means, for obtaining a phase offset between a carrier and a local oscillation; an autocorrelation calculating means, for calculating an autocorrelation and related statistics of the phase offset; and a filter coefficient determining means, for determining the coefficient of the filter in accordance with the autocorrelation and related statistics.Type: GrantFiled: July 13, 2010Date of Patent: August 20, 2013Assignee: Fujitsu LimitedInventors: Lei Li, Zhenning Tao, Ling Liu, Shoichiro Oda
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Patent number: 8514995Abstract: A circuit includes a receiver circuit, a data valid monitor circuit, a clock signal generation circuit, and a phase shift circuit. The receiver circuit is operable to generate a first periodic signal, a sampled data signal based on an input data signal, and a data valid signal based on a predefined number of bits in the sampled data signal. The data valid monitor circuit is operable to generate a count value by counting periods of the first periodic signal. The data valid monitor circuit is operable to generate a phase error signal based on the data valid signal and the count value. The clock signal generation circuit is operable to generate a second periodic signal. The phase shift circuit is operable to generate a third periodic signal based on the second periodic signal and to adjust a phase of the third periodic signal based on the phase error signal.Type: GrantFiled: April 7, 2011Date of Patent: August 20, 2013Assignee: Altera CorporationInventors: Boon Hong Oh, Peter Schepers, Da Hai Tang