Particular Error Voltage Control (e.g., Intergrating Network) Patents (Class 331/17)
  • Patent number: 8890626
    Abstract: One or more techniques and systems for a divider-less phase locked loop (PLL) and associated phase detector (PD) are provided herein. In some embodiments, a pulse phase detector (pulsePD) signal, a voltage controlled oscillator positive differential (VCOP) signal, and a voltage controlled oscillator negative differential (VCON) signal are received. An up signal and a down signal for a first charge pump (CP) and an up signal and a down signal for a second CP are generated based on the pulsePD signal, the VCOP signal, and the VCON signal. For example, CP signals are generated to control the first CP and the second CP, respectively. In some embodiments, CP signals are generated such that the CPs facilitate adjustment of a zero crossing phase of the VCON and VCOP signals with respect to the pulsePD signal. In this manner, a divider-less PLL is provided, thus mitigating PLL power consumption.
    Type: Grant
    Filed: August 15, 2012
    Date of Patent: November 18, 2014
    Assignee: Taiwan Semiconductor Manufacturing Company Limited
    Inventors: Yen-Jen Chen, I-Ting Lee, Hsieh-Hung Hsieh, Chewn-Pu Jou, Fu-Lung Hsueh, Shen-Iuan Liu
  • Patent number: 8884671
    Abstract: A phase-locked loop system has a controlled oscillator that provides an output clock signal based on a oscillator control signal, a feedback path configured to provide a feedback signal based on the output clock signal, a phase detector configured to provide a phase dependent signal based on the feedback signal and a reference clock signal, a phase evaluation block configured to provide the oscillator control signal based on the phase dependent signal, a frequency detector that determines whether the frequency ratio between the output clock signal and the reference clock signal has a desired value, and a control logic. The control logic is configured to, during a start-up period, disable the phase evaluation block upon determination of the desired value of the frequency ratio; detect, after disabling the phase evaluation block, a subsequent clock edge of the reference clock signal; and enable, in response to the detection of the subsequent clock edge, the phase evaluation block.
    Type: Grant
    Filed: April 11, 2014
    Date of Patent: November 11, 2014
    Assignee: Synopsys, Inc.
    Inventor: Jan Grabinski
  • Patent number: 8884706
    Abstract: Embodiments of the invention include a method for use in a device having a local oscillator. The method includes performing, for the local oscillator that is disciplined by an external reference signal, while locked to the external reference signal, training at least two mathematical models of the oscillator to determine a predicted correction signal for each mathematical model based at least in part on a correction signal that is a function of the external reference signal and which is used to discipline drift in the oscillator. The method also includes selecting a mathematical model of the at least two mathematical models that results in a smallest time error when disciplining the oscillator to use when the external reference signal is unavailable and an alternative correction signal is to be used to discipline drift in the oscillator.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: November 11, 2014
    Assignee: BlackBerry Limited
    Inventors: Charles Nicholls, Philippe Wu
  • Patent number: 8884704
    Abstract: Embodiments of the present invention enable a feedback-based VCO linearization technique. Embodiments include a frequency locked loop formed by feeding back a VCO's output into the VCO's input in negative phase by means of a frequency-to-voltage (F/V) converter. Embodiments enable constant VCO gain over a wide input tuning range and across PVT variations. Further, embodiments can be nested within a PLL, for example, with negligible area and power consumption overhead.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: November 11, 2014
    Assignee: Broadcom Corporation
    Inventors: Michael Youssef, Ahmad Mirzaei, Hooman Darabi
  • Patent number: 8878614
    Abstract: A PLL circuit includes an oscillator, a detection block, an integral path and a proportional path. The oscillator generates an oscillation signal. The detection block detects a phase difference between the oscillation signal and a reference signal and generates an integral signal that represents an integral value of the phase difference and a proportional signal that represents a current value of the phase difference. The integral path includes a regulator that receives the integral signal and supplies a regulated integral signal to the oscillator, and the regulator has a feedback loop including an error amplifier. The proportional path supplies the proportional signal, separately from the integral signal, to the oscillator. The oscillator generates the oscillation signal having an oscillation frequency controlled by both of the regulated integral signal and the proportional signal such that the phase of the oscillation signal is locked to the phase of the reference signal.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: November 4, 2014
    Assignee: MegaChips Corporation
    Inventors: Wenjing Yin, Anand Gopalan
  • Patent number: 8872556
    Abstract: A phase-locked loop circuit using a multi-curve voltage-controlled oscillator (VCO) having a set of operating curves, each operating curve corresponding to a different frequency range over a control voltage range. The phase-locked loop circuit includes a phase and frequency detector driving a charge pump and a digital control circuit configured to generate a curve select signal using a closed loop curve search operation to select one of the operating curves in the multi-curve VCO, the selected operating curve being used by the VCO to generate an output signal with an output frequency being equal or close to a target frequency of the phase-locked loop. In one embodiment, the digital control circuit increases the charge pump current above a nominal current value during the closed loop curve search operation and set the charge pump current to the nominal current value after an operating curve is selected.
    Type: Grant
    Filed: April 30, 2013
    Date of Patent: October 28, 2014
    Assignee: Micrel, Inc.
    Inventors: Juinn-Yan Chen, Wei-Kang Cheng
  • Patent number: 8860478
    Abstract: The invention provides a phase-locked loop with loop gain calibration and methods for measuring an oscillator gain, gain calibration and jitter measurement for a phase-locked loop. The method for measuring an oscillator gain of a phase-locked loop includes the steps of providing a varying code at an input end of the oscillator; outputting excess reference phase information by a reference phase integral path and outputting excess feedback phase information based on the varying code by a feedback phase integral path; and obtaining an estimated gain information of the oscillator based on the excess reference phase information and the excess feedback phase information.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: October 14, 2014
    Assignee: National Chiao Tung University
    Inventors: Wei-Zen Chen, Shu-Chin Chuang
  • Publication number: 20140292417
    Abstract: A voltage-controlled oscillator (VCO) module combines a low VCO-gain value with compensation for large frequency drifts. The VCO module comprises a VCO circuit and a time-integrator. The VCO circuit is fed with a first frequency tuning voltage and a second frequency tuning voltage which is produced by the time-integrator from the first frequency tuning voltage. In some embodiments, the time-integrator may be comprised of a transconductor connected in series with a capacitor, and the transconductor may have a linear operation range with low slope or zero-slope, located between two side ranges with deeper slope.
    Type: Application
    Filed: March 27, 2014
    Publication date: October 2, 2014
    Applicant: ASAHI KASEI MICRODEVICES CORPORATION
    Inventors: David Canard, Matthieu Lecuyer
  • Patent number: 8847653
    Abstract: A dither control circuit includes a pseudo random number generator, which generates a pseudo random number sequence in response to a frequency-divided clock signal, and a dither circuit which dithers an input digital code by using at least one output bit of the pseudo random number sequence and outputs a dithered digital code corresponding to a result of the dithering. The dither circuit may output, as the dithered digital code, a digital code corresponding to a sum of or a difference between the input digital code and the input digital code based on the at least one output bit. The dithered digital code may be input to an accumulator which operates in-sync with the frequency-divided clock signal.
    Type: Grant
    Filed: January 9, 2013
    Date of Patent: September 30, 2014
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jong Phil Hong, Jenlung Liu, Nan Xing, Jae Jin Park
  • Patent number: 8847690
    Abstract: Aspects of the embodiments include a method for synchronizing a device having an oscillator to a reference signal. A correction signal can be determined based on the reference signal. A mathematical model of the oscillator can be trained based at least upon the correction signal. A predicted correction signal for the trained mathematical model can be determined. A time error using the predicted correction signal can be generated to assess suitability of the trained mathematical model for disciplining drift in the oscillator and synchronizing the device when the reference signal is not available.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: September 30, 2014
    Assignee: BlackBerry Limited
    Inventors: Charles Nicholls, Philippe Wu
  • Publication number: 20140266472
    Abstract: In some embodiments, provided are AFC circuits and methods for calibrating a second setting of an oscillator while a first setting is controlled by a temperature compensated control.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Inventors: Jeffrey W. Waldrip, Yongping Fan, Jing Li
  • Patent number: 8830001
    Abstract: A new all digital PLL (ADPLL) circuit and architecture and the corresponding method of implementation are provided. The ADPLL processes an integer and a fractional part of the phase signal separately, and achieves power reduction by disabling circuitry along the integer processing path of the circuit when the ADPLL loop is in a locked state. The integer processing path is automatically enabled when the loop is not in lock. Additional power savings is achieved by running the ADPLL on the lower-frequency master system clock, which also has the effect of reducing spur levels on the signals.
    Type: Grant
    Filed: June 5, 2008
    Date of Patent: September 9, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Jingcheng Zhuang, Robert Bogdan Staszewski
  • Patent number: 8810320
    Abstract: In a circuit having a runaway detector coupled to a phase-locked loop (PLL), the PLL may include a loop filter to receive a control voltage within the PLL and provide a filtered control voltage and a voltage-controlled oscillator to receive the filtered control voltage and provide an output clock signal. The runaway detector may provide a control signal for adjusting the filtered control voltage in response to a predetermined PLL condition. The runaway detector may include a comparator to receive a first and second input voltages, where the second input voltage is based on the output clock signal. When the predetermined PLL condition exists, the runaway detector may be active to adjust the filtered control voltage, thereby enabling the PLL to return to a lock condition.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: August 19, 2014
    Assignee: Marvell Israel (M.I.S.L)
    Inventor: Mel Bazes
  • Patent number: 8803627
    Abstract: A Direct VCO (DCO) modulation apparatus and method that provides a wideband modulated signal output. The wideband response is obtained via signal processing to counteract a high-pass frequency characteristic as seen from the VCO modulation input. That is, low frequency components of data signals are compensated before being applied to a VCO input. The high-pass characteristic in combination with the compensated signal provides a relatively flat, wideband frequency response of the DCO modulator.
    Type: Grant
    Filed: December 3, 2013
    Date of Patent: August 12, 2014
    Assignee: Innophase Inc.
    Inventors: Yang Xu, Sara Munoz Hermoso, Xi Li
  • Publication number: 20140218119
    Abstract: One embodiment of communication system comprises a crystal oscillator configured to output a reference clock; cellular radio frequency (RF) and baseband phase locked loops configured to receive the reference clock within a cellular module and compensate for calculated frequency errors between a received cellular downlink signal and a cellular local oscillator signal during operation of the cellular module; global positioning system (GPS) frequency compensation circuitry configured to receive the reference clock within a GPS module and compensate for calculated frequency errors during operation of the GPS module; and a temperature sensing circuit which includes a plurality of sensing resistors and is configured to output a signal corresponding to a temperature of a reference crystal which is translated to a frequency deviation, wherein the (GPS) frequency compensation circuitry is configured to offset the frequency deviation and output a temperate compensated signal to meet GPS clock frequency requirements.
    Type: Application
    Filed: February 3, 2014
    Publication date: August 7, 2014
    Applicant: Broadcom Corporation
    Inventor: Rong He
  • Patent number: 8791736
    Abstract: This invention provides a loop filter device and a method for IC designers to adjust the pole or zero location of a phase lock loop (PLL) circuit. The pole and zero location are controlled by an amplifier and some on-chip resistor and capacitor components. The effective capacitance is magnified by the gain of the amplifier. The advantage of the loop filter device and the method according to embodiments of the present invention provides a feasible way to achieve a very low bandwidth in the PLL circuit without a huge external surface-mount capacitor.
    Type: Grant
    Filed: March 3, 2014
    Date of Patent: July 29, 2014
    Inventor: Yen Dang
  • Patent number: 8791755
    Abstract: A self-oscillating driver circuit includes a driver stage, a feedforward path which is coupled to an input of the driver stage, and a feedback path which couples an output of the driver stage to an input of the feedforward path. The feedforward path includes a feedforward filter which is designed as an active filter. In order to prevent an oscillatory state of the driver circuit at an unwanted frequency, it is proposed that an internal state variable of the feedforward filter be monitored and that the feedforward filter be reset if the value of the monitored internal state variable is outside a predefined range.
    Type: Grant
    Filed: October 6, 2011
    Date of Patent: July 29, 2014
    Assignee: Lantiq Deutschland GmbH
    Inventors: Dario Giotta, Thomas Poctscher, David San Segundo Bello, Andreas Wiesbauer
  • Publication number: 20140203726
    Abstract: An oscillation circuit includes: a ramp voltage generating unit configured to generate a ramp voltage; and a clock signal generating unit configured to generate a clock signal. The clock signal generating unit includes: a bias unit configured to apply one of the ramp voltage and a fixed voltage, as a bias voltage, to a resistor; and an oscillator configured to determine an oscillation frequency of the clock signal in response to a bias current flowing through the resistor.
    Type: Application
    Filed: January 21, 2014
    Publication date: July 24, 2014
    Applicant: ROHM CO., LTD.
    Inventor: Koji Katsura
  • Patent number: 8786347
    Abstract: In an embodiment, a delay circuit includes a ring oscillator circuit and a counter circuit. The ring oscillator circuit includes a delay chain having delay elements and configured to generate one of more clock cycles of an oscillator clock signal in response to a clock cycle of a clock signal. The counter circuit includes two counters that are configured to store a count state corresponding to a number of clock cycles of the oscillator clock signal during a single clock cycle of the clock signal. A first buffer is configured to store the number of clock cycles of the oscillator clock signal. The delay circuit includes a buffer to store a bit pattern corresponding to a number of delay elements traversed in a partial clock cycle of the oscillator clock signal in response to the clock cycle of the clock signal based on outputs of the plurality of delay elements.
    Type: Grant
    Filed: May 14, 2013
    Date of Patent: July 22, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Abhishek Chakraborty, Nagalinga Swamy Basayya Aremallapur, Vikas Narang
  • Patent number: 8773207
    Abstract: An object is to provide a PLL having a wide operating range. Another object is to provide a semiconductor device or a wireless tag which has a wide operating range in a communication distance or temperature by incorporating such a PLL. The semiconductor device or the wireless tag includes a first divider circuit; a second divider circuit; a phase comparator circuit to which an output of the first divider circuit and an output of the second divider circuit are provided; a loop filter to which an output of the phase comparator circuit is supplied and in which a time constant is switched in accordance with an inputted signal; and a voltage controlled oscillator circuit to which an output of the loop filter is supplied and which supplies an output to the second divider circuit.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: July 8, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Kiyoshi Kato, Takanori Matsuzaki
  • Publication number: 20140184343
    Abstract: A voltage controlled oscillator (VCO) includes a current controlled oscillator, a voltage-to-current converter, and a sensing circuit. The sensing circuit includes a delay unit, and the sensing circuit is configured to generate a plurality of compensation control signals in response to a time delay of the delay unit. The voltage-to-current converter is configured to generate a current signal in response to a VCO control signal and the plurality of compensation control signals. The current controlled oscillator is configured to generate an oscillating signal in response to the current signal.
    Type: Application
    Filed: December 31, 2012
    Publication date: July 3, 2014
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventor: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
  • Patent number: 8766680
    Abstract: A voltage translation circuit (116) provides an output analog voltage signal that has a translated voltage of the voltage of an input analog voltage signal over a range of values of the input analog voltage signal. The voltage translation circuit includes an input stage (202) having a circuit node and an input transistor (210) coupled between the circuit node and a power supply terminal, wherein a gate of the input transistor is coupled to receive the input analog voltage signal; a current path circuit (204) in parallel with the input transistor, wherein the current path includes a first transistor coupled between the circuit node and the power supply terminal; and a circuit coupled to provide a variable body bias voltage to a body of the first transistor.
    Type: Grant
    Filed: September 26, 2012
    Date of Patent: July 1, 2014
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Xinghai Tang, Gayathri A. Bhagavatheeswaran, Hector Sanchez
  • Patent number: 8754714
    Abstract: Disclosed is a statistical reference oscillator that includes: a stochastic reference clock generator which receives an input data outputs a reference signal obtained by dividing the received input data at a first frequency division ratio; a frequency divider which divides the frequency of an output signal at a second frequency division ratio and outputs a feedback signal; a frequency detector which outputs a difference signal based on a difference between the reference signal and the feedback signal; and an output signal generator which outputs the output signal based on the difference signal.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: June 17, 2014
    Assignee: Terasquare Co., Ltd.
    Inventors: Hyeon-Min Bae, Jinho Han
  • Patent number: 8754713
    Abstract: In an ADPLL composed of a digital circuit, a technique improving phase difference detection in a vicinity of a phase difference of 0 (zero) is provided. A feedback loop comprises a PFD comparing phases and frequencies of a reference signal and a feedback signal, a TDC converting an output of the PFD into a digital value, a DLF removing a high frequency noise component from an output of the TDC, a DCO controlled based on an output of the DLF and a DIV frequency-dividing an output the DCO and outputting the feedback signal. An offset value is added at any portion of the feedback loop, a phase of the feedback signal is controlled and a value other than 0 is inputted to the TDC even when the ADPLL is locked.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: June 17, 2014
    Assignees: Renesas Electronics Corporation, Epoch Microelectronics, Inc.
    Inventors: Toshiya Uozumi, Keisuke Ueda, Mitsunori Samata, Satoru Yamamoto, Russell P Mohn, Aleksander Dec, Ken Suyama
  • Patent number: 8736385
    Abstract: The embodiments described herein provide a voltage controlled oscillator (VCO). The VCO may include, but is not limited to a voltage-to-current converter configured to receive a control voltage and to convert the control voltage to a current, a current bias circuit coupled to the voltage-to-current converter and configured to receive frequency band select digital inputs and to bias the current generated by the voltage-to-current converter based upon the band select inputs, and a ring oscillator coupled to receive the biased current and to output an oscillating signal based upon the biased current.
    Type: Grant
    Filed: July 27, 2011
    Date of Patent: May 27, 2014
    Assignee: GLOBALFOUNDRIES, Inc.
    Inventors: Sreenivasa Chalamala, Dieter Hartung
  • Patent number: 8736394
    Abstract: To provide a reference frequency generating device that can output a highly accurate reference frequency signal even if a reference signal becomes unable to be acquired. The reference frequency generating device includes a synchronization circuit, a temperature sensor, and a controller. The synchronization circuit controls a reference frequency signal outputted from a voltage controlled oscillator, by a control signal obtained based on a reference signal. The temperature detector detects a temperature of the voltage controlled oscillator being used. When the reference signal is unable to be acquired, the controller corrects a voltage controlled signal in consideration of a distortion in the aging characteristic of the voltage controlled oscillator based on a rate of change with time in a slope of the oscillator temperature, and generates a holdover control signal based on corrected contents to control the voltage controlled oscillator.
    Type: Grant
    Filed: January 7, 2011
    Date of Patent: May 27, 2014
    Assignee: Furuno Electric Co., Ltd.
    Inventor: Shinya Kowada
  • Patent number: 8723607
    Abstract: A phase locked loop comprising: an oscillator for generating an output signal of a frequency that is dependent on an input to the oscillator; sampling means for generating a sequence of digital values representing the output of the oscillator at moments synchronized with a reference frequency; a difference unit for generating a feedback signal representing the difference between successive values in the sequence; and an integrator for integrating the difference between the feedback signal and a signal of a desired output frequency; the signal input to the oscillator being dependent on the output of the integrator.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: May 13, 2014
    Assignee: Cambridge Silicon Radio Limited
    Inventors: Michael Story, Nicolas Sornin
  • Patent number: 8723567
    Abstract: This invention provides a loop filter device and a method for IC designers to adjust the pole or zero location of a phase lock loop (PLL) circuit. The pole and zero location are controlled by an amplifier and some on-chip resistor and capacitor components. The effective capacitance is magnified by the gain of the amplifier. The advantage of the loop filter device and the method according to embodiments of the present invention provides a feasible way to achieve a very low bandwidth in the PLL circuit without a huge external surface-mount capacitor.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: May 13, 2014
    Inventor: Yen Dang
  • Patent number: 8717075
    Abstract: A phase locked loop circuit includes a phase frequency detector, a control circuit, a charge pump, a loop filter, a supply circuit, a ring oscillator, a frequency divider and a voltage detector. The phase frequency detector generates a frequency-increasing signal and a frequency-decreasing signal according to a phase difference between an input signal and a feedback signal. The control circuit generates a first control signal and/or a second control signal according to the frequency-increasing signal and the frequency-decreasing signal. The charge pump generates a current signal according to the first control signal and/or the second control signal. The voltage detector monitors a supply voltage of the supply circuit, and controls the control circuit to generate only the second control signal so as to reduce the supply voltage if the supply voltage is greater than a high reference voltage.
    Type: Grant
    Filed: April 22, 2013
    Date of Patent: May 6, 2014
    Assignees: Global Unichip Corp., Taiwan Semiconductor Manufacturing Co., Ltd.
    Inventor: Chun-Chi Chang
  • Patent number: 8717107
    Abstract: An object is to provide a PLL having a wide operating range. Another object is to provide a semiconductor device or a wireless tag which has a wide operating range in a communication distance or temperature by incorporating such a PLL. The semiconductor device or the wireless tag includes a first divider circuit; a second divider circuit; a phase comparator circuit to which an output of the first divider circuit and an output of the second divider circuit are provided; a loop filter to which an output of the phase comparator circuit is supplied and in which a time constant is switched in accordance with an inputted signal; and a voltage controlled oscillator circuit to which an output of the loop filter is supplied and which supplies an output to the second divider circuit.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: May 6, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Kiyoshi Kato, Takanori Matsuzaki
  • Patent number: 8710938
    Abstract: An electronic device may include a voltage controlled oscillator (VCO) and a temperature sensor. The electronic device may also include a controller configured to cooperate with the VCO and the temperature sensor to determine both a temperature and a frequency error of the VCO for each of a plurality of most recent samples. Each of the most recent samples may have a given age associated therewith. The controller may also be configured to align the temperature, the frequency error, and the given age for each of most recent samples in a three-dimensional (3D) coordinate system having respective temperature, frequency error and age axes. The controller may also be configured to estimate a predicted frequency error of the VCO based upon the aligned temperature, frequency error, and given age of the most recent samples.
    Type: Grant
    Filed: August 3, 2011
    Date of Patent: April 29, 2014
    Assignee: BlackBerry Limited
    Inventors: Grant Henry Robert Bartnik, Ryan Jeffrey Hickey
  • Publication number: 20140104005
    Abstract: A voltage controlled oscillator includes a voltage-to-current converter and a current controlled oscillator, where the voltage-to-current converter is used for converting an input voltage to generate an output current, and the current controlled oscillator is used for generating an output frequency signal according to the output current. In addition, the voltage-to-current converter includes an input terminal, a resistor, a current mirror and a current generating circuit, where the input terminal is for receiving the input voltage; the resistor is coupled to the input terminal; the current mirror is coupled to the resistor, and is used for mirroring a reference current to generate a mirrored current, where the reference current is formed according to at least a current flowing through the resistor; and the current generating circuit is coupled to the current mirror, and is used for generating the output current according to at least the mirrored current.
    Type: Application
    Filed: March 13, 2013
    Publication date: April 17, 2014
    Inventor: Huajiang Zhang
  • Patent number: 8698568
    Abstract: An automatic self-calibrated oscillation method and an apparatus using the same are provided. After a static time tuning (STT) table and a run time tuning (RTT) table have been established, the apparatus converts an output clock signal to generate a current RTT value at every predefined time and then compares the current RTT value with a reference RTT value generated in response to a STT value of the STT table, or with an interpolated result generated in response to the reference RTT value to generate a deviation value. Thus, through the deviation value, the output clock signal may be calibrated to address the target frequency without the assistance of external reference clock unit or locked loop unit after the STT table and the RTT table are established.
    Type: Grant
    Filed: April 26, 2012
    Date of Patent: April 15, 2014
    Assignee: Silicon Integrated Systems Corp.
    Inventors: Song Sheng Lin, Chia-Yi Chu
  • Patent number: 8686797
    Abstract: There is provided a phase locked loop circuit which includes a frequency divider, a phase comparator, a filter, and an output signal oscillator. The frequency divides a feedback signal by a specific ratio and the feedback signal is used for synchronizing a phase of a reference signal and a phase of an output signal. The phase comparator compares the phases of the reference signal, the output signal, and the feedback signal and adjusts a gain of an analog signal used for generating the output signal in accordance with increase or decrease of the ratio. The filter filters the analog signal to pass signals in a specific frequency band, the gain of the analog signal having been adjusted by the phase comparator and the output signal oscillator outputs the output signal on the basis of the analog signal.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: April 1, 2014
    Assignee: Fujitsu Limited
    Inventor: Ken Atsumi
  • Publication number: 20140085011
    Abstract: The inventive concept relates to a supply regulated voltage controlled oscillator having a function of an active loop filter by sharing one operational amplifier without additional use of active elements in a supply regulated voltage controlled oscillator using an operational amplifier as a supply regulator, and a phase locked loop using the same.
    Type: Application
    Filed: June 25, 2013
    Publication date: March 27, 2014
    Inventors: Woo-Young Choi, Kwang-Chun Choi
  • Patent number: 8674772
    Abstract: An oscillating signal generator utilized in a phase-locked loop (PLL) includes: an oscillating circuit arranged to generate an oscillating signal according to at least a first control signal; and a control circuit, arranged to adjust the first control signal according to a temperature; and the first control signal is tuned between a first boundary and a second boundary, and when the temperature is closer to a first temperature boundary than a second temperature boundary, and the control circuit is arranged to make the first control signal to be closer to the first boundary than the second boundary such that the oscillating circuit outputs the oscillating signal of a predetermined frequency in a locked mode of the PLL.
    Type: Grant
    Filed: March 26, 2012
    Date of Patent: March 18, 2014
    Assignee: Mediatek Inc.
    Inventor: Chih-Hsien Shen
  • Patent number: 8669817
    Abstract: A technique and corresponding circuitry are presented for a process independent, self-calibrating relaxation based clock source. The technique and circuitry presented here can reduce the time and cost needed for calibration significantly. The relaxation based clock source produces a clock signal whose frequency is dependent upon a trim value. Starting from an initial trim value, the clock signal is generated, its frequency is compared with a reference clock frequency value, and the trim value is correspondingly adjusted up or down a bit at a time. After this process has continued for a while, min-max logic is used to determine the maximum and minimum trim values and, based on these, the final trim value for the clock is set. This calibration process can also be used to extract whether, and by how much, the implementation on silicon of a particular chip lies in the fast or slow process corners.
    Type: Grant
    Filed: November 21, 2011
    Date of Patent: March 11, 2014
    Assignee: SanDisk Technologies Inc.
    Inventors: Deepak Pancholi, Bhavin Odedara, Naidu Prasad, Srikanth Bojja, Srinivasa Rao Sabbineni, Jayaprakash Naradasi
  • Patent number: 8669816
    Abstract: An integrated circuit device includes at least one controllable oscillator including a first control port and at least one further control port, at least one frequency control module including an output arranged to provide a frequency control signal. The at least one controllable oscillator further includes at least one compensation module including an output arranged to provide at least one compensation signal. The at least one compensation module includes an integrator component arranged to receive at an input thereof a signal that is representative of a difference between the indication of the frequency control signal and a reference signal, and to output an integrated difference signal. The at least one compensation module is arranged to generate the at least one compensation signal based at least partly on the integrated difference signal output by the integrator component.
    Type: Grant
    Filed: October 14, 2011
    Date of Patent: March 11, 2014
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: Yen-Horng Chen, Augusto Marques, Caiyi Wang
  • Patent number: 8643439
    Abstract: An oscillation circuit of a semiconductor apparatus includes a first level regulation unit configured to regulate an output voltage at an output node according to a difference between a reference voltage and the output voltage, and a second level regulation unit coupled between a power supply voltage terminal and a source voltage terminal.
    Type: Grant
    Filed: August 27, 2011
    Date of Patent: February 4, 2014
    Assignee: SK Hynix Inc.
    Inventor: Kwan Dong Kim
  • Patent number: 8638146
    Abstract: A method of measuring a phase difference for use in a phase locked loop (PLL) that includes a binary phase detector (BPD), a time-to-digital converter (TDC) and a signal generator, the phase difference being that between a reference signal and a generated signal output from the signal generator. The method includes inputting the reference signal and the generated signal into the TDC; measuring the magnitude of the phase difference at the TDC; if the measured magnitude of the phase difference is less than a threshold value, operating the PLL according to a first operational mode in which the output of the BPD controls the signal generator; and if the measured magnitude of the phase difference is greater than the threshold value, operating the PLL according to a second operational mode in which the output of the TDC and the BPD controls the signal generator.
    Type: Grant
    Filed: July 31, 2012
    Date of Patent: January 28, 2014
    Assignee: Cambridge Silicon Radio Limited
    Inventors: Pasquale Lamanna, Davide Orifiamma
  • Patent number: 8638173
    Abstract: A method of calibrating a phase-locked loop (PLL) while maintaining lock includes detecting that a control signal to an oscillator in a PLL has exceeded a threshold value while the PLL is locked to an input signal. In response, an operating current of the oscillator is adjusted to return the control signal below the threshold value while maintaining lock of the PLL to the input signal. Adjusting the operating current includes slowly varying an output current of a calibration circuit coupled to the PLL, enabling the PLL to maintain lock to the input signal during adjustment of the operating current.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: January 28, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Glenn A. Murphy, Xiaohua Kong, Nam V. Dang
  • Patent number: 8629728
    Abstract: A voltage-controlled oscillator (VCO) control circuit, used for controlling a VCO to process phase locking procedure after receiving a frequency locking signal, comprises an operating frequency controller and a judgment unit. The operating frequency controller, coupled to the VCO and the judgment unit, generates one of a first control code and a second control code to the VCO. The judgment unit, coupled to an input end of the VCO, generates a phase locking signal according to a voltage control signal inputted to the VCO. When the operating frequency controller receives the frequency locking signal, the operating frequency controller generates a first control code to control the VCO to switch from a first candidate VCO curve to a second candidate VCO curve. When the operating frequency controller receives the phase locking signal, the operating frequency controller generates a second control code to control the VCO to switch from the second candidate VCO curve to the first candidate VCO curve.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: January 14, 2014
    Assignee: MStar Semiconductor, Inc.
    Inventors: Yao-Chi Wang, Ming-Yu Hsieh, Shih-Chieh Yen
  • Patent number: 8618886
    Abstract: A hybrid numeric-analog clock synchronizer, for establishing a clock or carrier locked to a timing reference. The clock may include a framing component. The reference may have a low update rate. The synchronizer achieves high jitter rejection, low phase noise and wide frequency range. It can be integrated on chip. It may comprise a numeric time-locked loop (TLL) with an analog phase-locked loop (PLL). Moreover a high-performance number-controlled oscillator (NCO), for creating an event clock from a master clock according to a period control signal. It processes edge times rather than period values, allowing direct control of the spectrum and peak amplitude of the justification jitter. Moreover a combined clock-and-frame asynchrony detector, for measuring the phase or time offset between composite signals. It responds e.g. to event clocks and frame syncs, enabling frame locking with loop bandwidths greater than the frame rate.
    Type: Grant
    Filed: March 7, 2011
    Date of Patent: December 31, 2013
    Inventor: Christopher Julian Travis
  • Patent number: 8598955
    Abstract: A PLL including an adaptive loop filter. The PLL includes a feedback circuit which provides a feedback signal based on an output signal and a phase detector generating an adjust signal based on a frequency of the feedback signal compared with a reference frequency. A charge pump receives the adjust signal and provides a control voltage. The adaptive loop filter includes a capacitor and an adaptive resistance with a current control input. A VCO has an output providing the output signal based on a voltage level of the control voltage. A bias generator converts the control voltage to a loop bias current, and has a bias output based on the loop bias current coupled to the current control input of the adaptive resistance. The bias output of the bias generator may also be used to control the charge current and the VCO using currents proportional to the loop bias current.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: December 3, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Dashun Xue
  • Patent number: 8581667
    Abstract: A circuit includes a first path including a first transistor and a first current source. The first transistor is responsive to a tuning voltage. The circuit also includes a tuning voltage range extension circuit responsive to the tuning voltage. The tuning voltage range extension circuit is configured to selectively change current supplied by the first path as the tuning voltage exceeds a capacity threshold of the first transistor.
    Type: Grant
    Filed: November 11, 2011
    Date of Patent: November 12, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Swarna L. Navubothu, Cheng Zhong, Nam V. Dang, Xiaohua Kong
  • Patent number: 8575979
    Abstract: Provided is a fully differential adaptive bandwidth phase locked loop with differential supply regulation. One fully differential phase locked loop includes a differential active loop filter and regulator coupled to an output of a differential charge pump, a differential voltage-controlled oscillator coupled to differential control voltages developed by the differential active loop filter and regulator, and a bias circuit coupled to the differential control voltages and providing a bias current to the differential charge pump.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: November 5, 2013
    Assignee: Conexant Systems, Inc.
    Inventor: Chandrashekar Reddy
  • Patent number: 8570113
    Abstract: A method and circuitry for calibrating the gain of a VCO (voltage controlled oscillator) is disclosed. In one embodiment, a circuit includes a comparator configured to provide a first indication if the VCO gain is not within the specified gain range, and a second indication if the VCO is within the specified gain range. The circuit further includes a control unit configured to, upon occurrence of at least a first cycle of a clock signal, cause adjustment of the VCO gain responsive to receiving the first indication. For each one or more successive cycles of the clock signal, the control unit is configured to cause corresponding adjustments of the VCO gain until the comparator provides the second indication. The control unit is configured to discontinue adjustments to the VCO gain responsive to receiving the second indication.
    Type: Grant
    Filed: June 23, 2010
    Date of Patent: October 29, 2013
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Dennis M. Fischette
  • Patent number: 8571134
    Abstract: The present application relates to at least one digitally controlled oscillator and a data modulation device. More particularly, the digital polar transmitter comprises at least one digitally controlled oscillator configured to generate at least one frequency. The digital polar transmitter comprises a data modulation device, wherein the data modulation device comprises at least one data input terminal, at least one output terminal, and at least one frequency input terminal, wherein the output terminal is connected to the digitally controlled oscillator. The digital polar transmitter comprises a phase measuring device configured to measure phase information from the output signal of the data modulation device for every frequency sample.
    Type: Grant
    Filed: August 24, 2009
    Date of Patent: October 29, 2013
    Assignee: NXP, B.V.
    Inventors: Nenad Pavlovic, Manel Collados, Xin He, Jan Van Sinderen
  • Patent number: 8564345
    Abstract: Digitally controllable delay lines including fine grain and coarse grain delay elements, and methods and system to calibrate the delay lines in fine grain increments. Calibration may include calibrating a number of fine grain elements for which a combined delay is substantially equal to a delay of a coarse grain element, and calibrating numbers of fine grain and coarse grain elements which a combined delay corresponds to a period of a reference clock. A digitally controlled delay line may be implemented as part of a digital delay locked loop (DLL), and calibration parameters may be provided to a slave DLL having a similarly implemented delay line. A digitally controllable DLL may provide relatively low-power, high-resolution over a spectrum of process, voltage, and temperature variations, and may be implemented in relatively high-speed applications previously reserved for analog DLLs.
    Type: Grant
    Filed: April 1, 2011
    Date of Patent: October 22, 2013
    Assignee: Intel Corporation
    Inventor: Wing K. Yu
  • Patent number: RE44879
    Abstract: A phase locked loop has a controlled oscillator for outputting an oscillator signal depending on a control signal. A comparator generates a comparison result from a comparison between a reference frequency signal and a feedback signal derived from the oscillator signal. The phase locked loop also has a filter block for filtering the comparison result and for deriving the control signal from the comparison result, where the filter block has a loop filter and a rejection filter for the frequency-selective attenuation of at least one first interference frequency in the comparison result.
    Type: Grant
    Filed: April 5, 2012
    Date of Patent: May 6, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Thomas Mayer, Christian Wicpalek, Thomas Bauernfeind, Linus Maurer