| Entries |
| Document | Title | Date |
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| 20080238508 | Input Clock Detection Circuit for Powering Down a PLL-Based System - An apparatus is provided for detecting the loss of an input clock signal for a phase-locked loop (PLL). The apparatus includes a time delay circuit, a first frequency divider and a digital logic circuit. The time delay circuit receives the input clock signal and outputs a first time-delayed clock signal. The first frequency divider receives an input signal from an internal clock of the PLL and outputs a clock signal having the same frequency or a lower frequency than that of the time-delayed clock signal. The digital logic circuit that receives the first frequency divider output signal and the first time-delayed clock signal and outputs a signal indicating the loss of the input clock signal if there is no first time-delayed clock signal for a cycle of the first frequency divider output signal. | 10-02-2008 |
| 20080246521 | MULTIPLE REFERENCE FREQUENCY FRACTIONAL-N PLL (PHASE LOCKED LOOP) - A system and a method for operating the same. The system includes a fractional-N phase-locked loop (PLL). The PLL includes a PLL input and a PLL output. The fractional-N PLL further includes a multiplexer. The multiplexer includes a multiplexer output electrically coupled to the PLL input. The multiplexer further includes M multiplexer inputs, M being an integer greater than 1. Two or more reference frequencies are applied to the inputs of the multiplexer, by the selection of one from the reference frequencies, the low spur can be reached. | 10-09-2008 |
| 20080246522 | PHASE LOCKED LOOP AND METHOD FOR ADJUSTING THE FREQUENCY AND PHASE IN THE PHASE LOCKED LOOP - A phase locked loop (PLL) which includes a phase frequency detector coupled with a time to digital converter capable of comparing a reference signal with an oscillator signal and generating a digital value representing the phase difference between the reference signal and the oscillator signal. The PLL further includes a state machine for phase acquisition that is capable of generating a control value depending on the digital value, and a controllable oscillator that is capable of generating the oscillator signal depending on the control value. | 10-09-2008 |
| 20080297217 | METHOD AND APPARATUS FOR REDUCING INTERFERENCE - A method and apparatus is provided for reducing interference in circuits. A management strategy is provided to reduce reference spurs and interference in circuits. The management strategy uses a combination of one or more techniques which reduce the digital current, minimize mutual inductance, utilize field cancellation, prevent leakage current, and/or manage impedance. These techniques may be used alone, or preferably, used on combination with one another. | 12-04-2008 |
| 20080315928 | DIGITAL PHASE LOCKED LOOP WITH DITHERING - An embodiment of the present invention provides a phase locked loop that operates on clock signals derived from an RF clock signal generated by the phase locked loop. A frequency reference input provides a reference clock. A controllable oscillator generates the RF clock signal. A phase detection circuit operates on the reference clock to provide digital phase error samples indicative of a phase difference between the reference clock and the RF clock. A dithering circuit is coupled to the reference signal and injects a short sequence dither signal into the reference signal in order to overcome quantization noise and thereby improve RMS phase-error detection for integer channels. | 12-25-2008 |
| 20090015303 | Delay cell of voltage controlled delay line using digital and analog control scheme - Provided is an analog/digital control delay locked loop (DLL). The DLL includes a phase detector for detecting a phase difference between an input clock signal and a feedback signal to provide an up detection signal or a down detection signal, a charge pump for generating an adjusted output current based on the up or down signals, a loop filter for low pass-filtering the output current to produce an analog control voltage, a voltage controlled delay Line (VCDL) for receiving the analog control voltage, the input clock signal and a digital code, and delaying the input clock signal based on the analog control voltage and the digital code to provide an output clock signal, a delay replica modeling unit formed by replica of delay factors for producing the feedback signal depending on the output clock signal, and a digital code generator for generating the digital code. | 01-15-2009 |
| 20090045859 | Method and system for diagnostic imaging using a digital phase locked loop - A method and apparatus are provided for minimizing output pulse jitters in a phase locked loop. The method includes pre-setting the digital phase locked loop to a desired frequency, locking the digital phase locked loop to the desired frequency to generate an output signal, and filtering the output signal of the digital phase locked loop to maintain undesirable jitter to an acceptable range. In one embodiment, the apparatus is a medical imaging device. In another embodiment, the apparatus is a baggage imaging device. | 02-19-2009 |
| 20090085622 | PHASE-LOCKED LOOP START-UP TECHNIQUES - Implementations feature systems and techniques for phase-locked loops (PLLs). In some aspects, implementations feature a system that has a PLL circuit including an oscillator and programmable reference frequency divider circuit or a programmable feedback frequency divider circuit. The PLL includes a control circuit to reduce a time required for a PLL settling time by programming a division value into the programmable reference frequency divider circuit and/or the programmable feedback frequency divider circuit to target the oscillator to operate outside of a system operating frequency range of the oscillator during start-up of PLL operations. The control circuit can program another division value into the programmable reference frequency divider circuit and/or the programmable feedback frequency divider circuit after stabilization of the variable oscillator. | 04-02-2009 |
| 20090167389 | Voltage-Controlled Oscillator - The present invention discloses a calibration circuit for a voltage-controlled oscillator ( | 07-02-2009 |
| 20090189659 | SWITCHING CIRCUIT IN A PHASE LOCKED LOOP (PLL) TO MINIMIZE CURRENT LEAKAGE IN INTEGRATED CIRCUITS - In an apparatus and method for reducing current leakage in a phase locked loop (PLL), a pair of resistive divider circuit is coupled to receive a pair of differential input signals and provide a pair of differential output signals. A timing control circuit controls a pair of switches, the pair of switches being operable to conduct the pair of differential output signals in response to at least one signal of the pair of differential input signals being present. An operational amplifier (OA) includes a pair of OA input terminals and an OA output terminal. The pair of OA input terminals is coupled to receive the pair of differential output signals conducted by the pair of switches. A feedback circuit is coupled between the OA output terminal and a first one of the pair of OA input terminals. The pair of switches is disabled by the timing control circuit to block a current leakage from the feedback circuit. | 07-30-2009 |
| 20090195278 | METHOD AND CIRCUIT FOR CONTROLLING CLOCK FREQUENCY OF AN ELECTRONIC CIRCUIT WITH NOISE MITIGATION - A technique to mitigate noise spikes in an electronic circuit device such as an integrated circuit. The clock frequency of a clock signal used by the electronic circuit is controlled such that instantaneously large changes to the clock frequency are avoided by use of a frequency filter that is capable of generating frequency ramps having a linear slope which is used as a feedback signal in a digital phase-locked loop clock circuit in lieu of a discrete, stair-stepped feedback control signal. | 08-06-2009 |
| 20100001773 | DIGITAL PLL DEVICE - An input clock dividing unit frequency-divides an input clock, and an input clock multiplying unit frequency-multiplies the input clock. An operation clock selecting unit selects the frequency-divided clock when the input clock is fast and selects the frequency-multiplied clock when the input clock is slow, based on the frequency detection result of frequency detecting unit. The operation clock selecting unit then outputs the selected clock to a phase comparing unit as an operation clock. The phase comparing unit operates according to the frequency-divided or frequency-multiplied clock, and controls an oscillating unit so that the phase difference between a reference signal and a comparison signal becomes zero. The phase of an output clock is thus caused to track the phase of the reference signal. | 01-07-2010 |
| 20100013531 | PHASE-LOCKED LOOP CIRCUITS AND METHODS IMPLEMENTING PULSEWIDTH MODULATION FOR FINE TUNING CONTROL OF DIGITALLY CONTROLLED OSCILLATORS - PLL (phase locked loop) circuits and methods are provided in which PWM (pulse width modulation) techniques are to achieve continuous fine tuning control of DCO (digitally controlled oscillator) circuits. In general, pulse width modulation techniques are applied to further modulate dithered control signals that are used to enhance the frequency tuning resolution of the DCO such that the dithered control signals are applied to the fractional tracking control port of the DCO for a selected fraction of a full clock signal based pulse width modulation applied. | 01-21-2010 |
| 20100013532 | PHASE-LOCKED LOOP CIRCUITS AND METHODS IMPLEMENTING MULTIPLEXER CIRCUIT FOR FINE TUNING CONTROL OF DIGITALLY CONTROLLED OSCILLATORS - Circuits and methods are provided in which fine tuning control of a DCO (digitally controlled oscillator) circuit in a digital PLL circuit is realized by dither controlling a multiplexer circuit under digital control to selectively output one of a plurality of analog control voltages with varied voltage levels that are input to a fractional frequency control port of the DCO to drive tuning elements of the DCO at fractional frequency resolution and achieve continuous fine tuning of the DCO under analog control. | 01-21-2010 |
| 20100013533 | DIGITAL DELAY LINE AND APPLICATION THEREOF - A digital delay line includes a plurality of hysteresis-based delay cells electrically connected in series. These hystersis delay units in the hysteresis-based delay cells may be similar or different. All of the hysteresis delay units respectively have an inverter mode and a hesteresis mode. The delay and resolution of the hysteresis delay unit may be derived from the time difference in the inverter mode and hysteresis mode. Such a digital delay line applied to a digital phase locked loop may reduce consumption of area and power. | 01-21-2010 |
| 20100033220 | ACCUMULATED PHASE-TO-DIGITAL CONVERSION IN DIGITAL PHASE LOCKED LOOPS - Techniques for converting an accumulated phase of a signal into a digital value in a digital phase-locked loop (DPLL). In an exemplary embodiment, a signal is coupled to a divide-by-N module that divides the frequency of the signal down by a divider ratio N. The divided signal is input to a delta phase-to-digital converter, which measures the phase difference between a rising edge of the divided signal and a rising edge of a reference signal. The accumulated divider ratios and the measured phase differences are combined to give an accumulated digital phase. Further techniques for varying the divider ratio N using a sigma-to-delta modulator are disclosed. | 02-11-2010 |
| 20100052752 | LOCK DETECTION CIRCUIT AND LOCK DETECTING METHOD - Provided are a lock detection circuit and a lock detecting method. The lock detection circuit includes two delay devices, four flip-flops and two logic gates, and can accurately detect a lock state of a phase locked loop (PLL) circuit. Therefore, the lock detection circuit can be implemented in a simple structure, and as a result, the lock detection circuit can be compact in size and can consume less electric power. Also, the lock detecting method enables lock detection process to be simpler, so that a lock state can be detected within a short time period. | 03-04-2010 |
| 20100066421 | ADAPTIVE CALIBRATION FOR DIGITAL PHASE-LOCKED LOOPS - Techniques for adaptively calibrating a TDC output signal in a digital phase-locked loop (DPLL). In an exemplary embodiment, a calibration factor multiplied to the TDC output signal is adaptively adjusted to minimize a magnitude function of a phase comparator output signal of the DPLL. In an exemplary embodiment, the calibration factor may be adjusted using an exemplary embodiment of the least-mean squares (LMS) algorithm. Further techniques for simplifying the adaptive algorithm for hardware implementation are described. | 03-18-2010 |
| 20100073054 | Techniques For Digital Loop Filters - A digital loop filter includes a fine control circuit and a coarse control circuit. The fine control circuit adjusts a phase of a feedback clock signal by a first phase adjustment in response to a first phase error signal that indicates a sign of a phase error between a reference clock signal and the feedback clock signal. The coarse control circuit adjusts the phase of the feedback clock signal by a second phase adjustment in response to a second phase error signal. The second phase adjustment is larger than the first phase adjustment. The second phase error signal indicates a magnitude of a phase error between the reference clock signal and the feedback clock signal. | 03-25-2010 |
| 20100141313 | DIGITAL PHASE-LOCKED LOOP WITH TWO-POINT MODULATION AND ADAPTIVE DELAY MATCHING - A digital phase-locked loop (DPLL) supporting two-point modulation with adaptive delay matching is described. The DPLL includes highpass and lowpass modulation paths that support wideband and narrowband modulation, respectively, of the frequency and/or phase of an oscillator. The DPLL can adaptively adjust the delay of one modulation path to match the delay of the other modulation path. In one design, the DPLL includes an adaptive delay unit that provides a variable delay for one of the two modulation paths. Within the adaptive delay unit, a delay computation unit determines the variable delay based on a modulating signal applied to the two modulation paths and a phase error signal in the DPLL. An interpolator provides a fractional portion of the variable delay, and a programmable delay unit provides an integer portion of the variable delay. | 06-10-2010 |
| 20100141314 | ALL DIGITAL PHASE LOCKED LOOP CIRCUIT - An all digital phase locked loop circuit includes a reference frequency indicator for receiving a reference signal with a reference frequency and generating a frequency indicating value; a phase frequency detector for comparing the reference signal with a frequency divided signal and generating a phase difference pulse; a time-to-digital circuit for receiving the phase difference pulse and a plurality of output signals and generating a phase difference value; a digital controller for receiving the frequency indicating value and the phase difference value and generating a control value; a delta-sigma modulator for modulating the control value and generating a modulated control value; a DCO for receiving the modulated control value and generating an output oscillating signal with a digital controlled frequency; a frequency divider for dividing the digital controlled frequency to generate the frequency divided signal; and a multi-phase generator for receiving the output oscillating signal and generating the output signals. | 06-10-2010 |
| 20100141315 | APPARATUS FOR LINEARIZATION OF DIGITALLY CONTROLLED OSCILLATOR - There is provided an apparatus for the linearization of a digitally controlled oscillator. The apparatus includes a first filter outputting only a low frequency band signal of an input signal to the digitally controlled oscillator; a negative feedback loop causing the signal of an input port of the digitally controlled oscillator to pass through a frequency table and a frequency-to-digital code mapper in sequence and correcting an input of the digitally controlled oscillator by performing negative feedback to an input port of the first filter; and a frequency table generator storing a frequency value of an output signal of the digitally controlled oscillator in the frequency table. | 06-10-2010 |
| 20100141316 | METHOD OF IMPROVING NOISE CHARACTERISTICS OF AN ADPLL AND A RELATIVE ADPLL - An all-digital phase locked loop (ADPLL) generates a feedback word representing a continuous-time oscillating signal. The ADPLL includes a time-to-digital converter (TDC) configured to be input with the continuous-time oscillating signal and a reference signal. The reference signal is a function of a reference clock signal. The TDC is configured to generate a digital word, the feedback word being a function of the digital word. The ADPLL includes a delay circuit configured to be input with at least one of the reference clock signal and the continuous-time oscillating signal and to be controlled by a first dither signal. | 06-10-2010 |
| 20100148832 | Clock data recovery circuit - A simple circuit that supports high and low data rates is provided. The circuit includes: a detection circuit | 06-17-2010 |
| 20100164575 | DATA REPRODUCTION CIRCUIT - Provided is a data recovery circuit including an input data phase detection circuit for outputting a gate signal synchronized with a rising phase of input data, a gated multiphase oscillator for instantly generating N-phase clocks based on the gate signal as a trigger, data discriminating and reproducing circuits for outputting sampled data of the input data which are synchronized with the clocks, a continuous clock generation circuit for generating a continuous clock which is a reference clock, continuous clock synchronization circuits for synchronizing the sampled data with the continuous clock and outputting the synchronized sampled data as phase synchronization data, and a phase selector for selecting the phase synchronization data having an optimum discrimination phase with the largest phase margin with respect to the input data and outputting the selected phase synchronization data as recovery data. | 07-01-2010 |
| 20100182060 | Digital phase-locked loop - A digital phase-locked loop circuit includes: a first counter which counts a first clock; a second counter which counts third clocks into which a second clock is divided; a first phase detector which detects a relative phase difference between the first and the third clocks according to a first comparison result that clocks in which the third clock is delayed are compared with the first clock and a second comparison result that clocks in which the first clock is delayed are compared with the third clock; a second phase detector which measures the period of the second clock; a phase error calculating unit which calculates a phase difference between the first and the third clocks according to the value that the result detected by the first phase detector is normalized by the result detected by the second phase detector and the count values of the first and the second counters; and a DCO which outputs the second clock according to the result calculated by the phase error calculating unit. | 07-22-2010 |
| 20100182061 | DEVICE AND METHOD FOR PHASE SYNCHRONIZATION WITH THE AID OF A MICROCONTROLLER - A phase controller device according to the invention comprises a hardware core that is formed by a signal detector, a voltage-controlled oscillator, a phase comparator, and an integration unit, where the hardware core, by controlling the working clock pulse frequency of the microcontroller, brings an output clock pulse signal that is generated by a microcontroller into phase with the input clock pulse information that is received from the input data stream, and does so in such a manner that the jitter is low. The microcontroller executes a program with this working clock pulse, where with that program the microcontroller generates the output clock pulse signal with an output clock pulse frequency that is in a predetermined division ratio to the control clock pulse frequency that is generated by the voltage-controlled oscillator and is given to the microcontroller as a working clock pulse frequency. In this way the program enables the phase controller device according to the invention to process, with a microcontroller, external periodic signals, data, or events, where the software processes taking place in the microcontroller are always locked in phase with the periodic occurrence of these external signals, data, or events. | 07-22-2010 |
| 20100271091 | METHOD OF FAST TRACKING AND JITTER IMPROVEMENT IN ASYNCHRONOUS SAMPLE RATE CONVERSION - A method for fast tracking and jitter improvement in an asynchronous sample rate conversion includes a digital phase locked loop (DPLL) for an asynchronous sample rate conversion (ASRC) device. A control apparatus in the DPLL includes a gain controller that sets and maintains gains (K | 10-28-2010 |
| 20100289544 | Receiver With Enhanced Clock And Data Recovery - A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler. | 11-18-2010 |
| 20100315140 | Compensation Of Phase Lock Loop (PLL) Phase Distribution Caused By Power Amplifier Ramping - Disclosed herein are techniques, systems, and methods relating to compensation of phase disturbances of a phase lock-loop during power ramp up or down of a power amplifier. More specifically, a phase lock-loop is described that is able to switch between type I and type II PLL modes depending on the power state of the power amplifier without introducing additional disturbances. | 12-16-2010 |
| 20110025390 | UPDATE CONTROL APPARATUS IN DLL CIRCUIT - An update control apparatus in a DLL circuit is provided. The update control apparatus includes a logic value determination, a phase information collection unit, and an update control unit. The logic value determination unit is configured to determine a logic value of a phase detection signal for a first period interval of a reference clock signal to generate a phase information signal, and configured to extend the first period interval into a second period interval when an extension instruction signal is enabled. The phase information collection unit is configured to determine consecutive logic values of an update possible signal to generate the extension instruction signal, and configured to collect the phase information signal to generate an update information signal. The update control unit is configured to generate the update possible signal, a valid interval signal, and an update control signal in response to the update information signal. | 02-03-2011 |
| 20110037505 | TRANSCEIVER AND OPERATING METHOD THEREOF - A semiconductor chip area is reduced and the possibility of malfunction in generation of reproduction data and a reproduction clock is reduced. A transceiver comprises a clock data recovery circuit, a deserializer, a serializer, a PLL circuit, and a frequency detector. The clock data recovery circuit extracts a reproduction clock and reproduction data in response to a receive signal and a clock signal generated by the PLL circuit. The deserializer generates parallel receive data from the reproduction clock and the reproduction data, and the serializer generates a serial transmit signal from parallel transmit data and the clock signal. The detector detects a difference in frequency of the receive signal and the clock signal, and generates a frequency control signal. In response to the frequency control signal, the PLL circuit controls a cycle of the clock signal so as to reduce the difference in frequency. | 02-17-2011 |
| 20110089983 | LOOP TYPE CLOCK ADJUSTMENT CIRCUIT AND TEST DEVICE - A variable delay circuit applies a variable delay that corresponds to an analog signal to a reference clock so as to generate a delayed clock. A phase detection unit detects the phase difference between the delayed clock and the reference clock, and generates a phase difference signal having a level that corresponds to the phase difference. A counter performs a counting up operation or a counting down operation according to the level of the phase difference signal. A digital/analog converter converts the count value of the counter into an analog signal, and supplies the count value thus converted to the variable delay circuit. The counter comprises: a first counter configured to use a first thermometer code to count the lower group of digits of the count value according to the phase difference signal; a second counter configured to use a second thermometer code to count an upper group of digits of the count value according to the phase difference signal; and a control circuit configured to perform a control operation such that the Hamming distance is maintained at 1 even in a carry operation and a borrow operation of the first counter and the second counter. | 04-21-2011 |
| 20110148488 | DIGITAL PHASE LOCKED LOOP WITH CLOSED LOOP LINEARIZATION TECHNIQUE - Apparatuses, systems, and a method for providing a digital phase-locked loop (PLL) are described. In one embodiment, an apparatus includes an integration-mode phase frequency detector (PFD) that compares a phase and frequency of a reference clock signal to a phase and frequency of a generated feedback clock signal and generates a digitized output signal. A digital loop filter (DLF) receives the digitized output signal and applies a linearization technique to the digitized output signal. The DLF includes a derivative gain unit of a derivative path, a proportional gain unit of a proportional path, and an integral gain unit of an integral path. The derivative path provides a direct proportional feedback loop path to the integration-mode PFD by compensating the integration of an integrator that receives output signals from the paths. The integration-mode PFD can be implemented with a hybrid circuit or a substantially digital circuit. | 06-23-2011 |
| 20110148489 | Adaptive digital phase locked loop - In some embodiments, a digital PLL is disclosed with a dynamically controllable filter for changing the effective DPLL bandwidth in response to one or more real-time performance parameters such as phase error. | 06-23-2011 |
| 20110148490 | TIME-TO-DIGITAL CONVERTER AND ALL DIGITAL PHASE-LOCKED LOOP INCLUDING THE SAME - An all digital phase-locked loop (ADPLL) includes: a phase counter accumulating a frequency setting word value and the phase of a digitally controlled oscillator (DCO) clock and detecting a fine phase difference between a reference clock and a retimed clock; a phase detector detecting a digital phase error value compensating for a phase difference between the frequency setting word value and the DCO clock according to the fine phase difference to detect a digital phase error value; a digital loop filter filtering the digital phase error value and controlling PLL operational characteristics; a lock detector generating a lock indication signal according an output of the digital loop filter; a digitally controlled oscillator varying the frequency of the DCO clock according to the output from the digital loop filter; and a retimed clock generator generating the retimed clock by retiming the DCO clock at a low frequency. | 06-23-2011 |
| 20110156781 | DEVICE AND METHOD FOR PHASE COMPENSATION - A frequency generation unit is provided that permits a receiver to tune from channel to channel without cycle skipping and in which compensation for phase offset introduced during tuning is provided. The frequency generation unit includes a fractional-N synthesizer, a voltage controlled oscillator (VCO), and a direct digital synthesizer (DDS). The fractional-N synthesizer generates frequencies from the VCO as well as a temperature controlled crystal oscillator. Outputs from the fractional-N synthesizer are supplied both the VCO and the DDS to control the VCO and DDS. The combination of the voltage controlled oscillator and fractional-N synthesizer is perpetually locked. The fractional-N synthesizer is maintained in a locked condition. The VCO output is provided to the DDS. An output from the DDS or from the fractional-N synthesizer forms the output signal of the frequency generation unit. | 06-30-2011 |
| 20110156782 | ONION WAVEFORM GENERATOR AND SPREAD SPECTRUM CLOCK GENERATOR USING THE SAME - An onion waveform generator and a spread spectrum clock generator (SSCG) using the same are provided. The onion waveform generator includes a value generation unit and an accumulating unit. The value generation unit outputs a counting value. The accumulating unit accumulates the counting value to output a waveform value. The accumulating unit switches from an increasing mode to a decreasing mode if the waveform value is a third boundary value, and the accumulating unit switches from the decreasing mode to the increasing mode if the waveform value is a fourth boundary value. | 06-30-2011 |
| 20110156783 | DIGITAL PHASE LOCKED LOOP - A digital phase locked loop ( | 06-30-2011 |
| 20110187428 | Electrothermal frequency reference - An electrothermal frequency-locked loop (EFLL) circuit is described. This EFLL circuit includes an oscillator in a feedback loop. A drive circuit in the EFLL circuit generates a first signal having a fundamental frequency, and an electrothermal filter (ETF) in the EFLL circuit provides a second signal based on the first signal. This second signal has the fundamental frequency and a phase (relative to the first signal) that corresponds to a temperature-dependent time constant of the ETF. Moreover, a sensing component in the EFLL circuit determines a parameter associated with a temperature of the ETF. For example, the parameter may be the temperature or may be other than the temperature, such as the fundamental frequency and/or the phase of the second signal. Furthermore, the EFLL circuit includes a compensation circuit that compensates for frequency changes associated with changes in the temperature based at least on the parameter so that the fundamental frequency is approximately independent of the temperature. | 08-04-2011 |
| 20110204944 | DIGITAL LOCK DETECTOR AND FREQUENCY SYNTHESIZER USING THE SAME - There is provided a digital lock detector and a frequency synthesizer using the same. The digital lock detector includes a comparator unit receiving a plurality of control bits, and generating a bit signal to notice a lock condition of the plurality of control bits; a delay cell block generating a plurality of delay signals based on the bit signal, and outputting a clock signal by combining the bit signal and the plurality of delay signals; and a detection unit detecting a shift time of the clock signal, and generating a lock indication signal according to the detection result. | 08-25-2011 |
| 20110227621 | GAIN NORMALIZATION OF A TIME-TO-DIGITAL CONVERTER - The invention relates to normalisation of a TDC system ( | 09-22-2011 |
| 20110267120 | DELAY LINE CALIBRATION - In some embodiments, provided are calibration techniques for measuring mismatches between TDL delay stage elements, and in some cases, then compensating for the mismatches to minimize performance degradation. | 11-03-2011 |
| 20110273210 | LOW POWER DIGITAL PHASE LOCK LOOP CIRCUIT - A digital phase lock loop circuit, where under certain conditions the phase error is derived from phase comparison between a reference clock edge and the next oscillator clock edge rather than a feedback clock edge. This technique can be used to significantly reduce digital phase lock loop circuit power by disabling feedback divider and sync FF once initial frequency lock is established, provided phase jitter of digital phase lock loop circuit is low enough so that there is no cycle slip. This technique can also be used to multiply the effective reference clock frequency of digital phase lock loop circuits to increases the loop bandwidth, thus reducing the phase noise. Both the applications of this technique can be combined in some circuits. | 11-10-2011 |
| 20110285439 | Digital to Frequency Synthesis Using Flying-Adder with Dithered Command Input - To make Flying-Adder architecture even more powerful, a new concept, time-average-frequency, is incorporated into the clock generation circuitry. This is a fundamental breakthrough since it attacks the clock generation problem from its root: how is the clock signal used in real systems? By investigating from this direction, a much more powerful architecture, fixed-VCO-Flying-Adder architecture, is created. Furthermore, based on fixed-VCO-Flying-Adder frequency synthesizer and time-average-frequency, a new type of component called Digital-to-Frequency Converter (DFC) is born. | 11-24-2011 |
| 20120013377 | Digital Phase Locked Loop - An adaptive digital phase locked loop comprises: a digital configurable phase detector for receiving a reference signal and a feedback signal and for generating a detection signal indicative of a phase/frequency difference between the reference signal and the feedback signal; a configurable digital loop filter for filtering the DPFD detection signal; a digital locking monitor for monitoring polarity transitions of the detection signal and adaptively switching the locking modes and DCO tuning resolution; and a DCO for generating the feedback signal as a function of the detection signal. | 01-19-2012 |
| 20120019297 | Systems And Methods For Electricity Metering - In one aspect, the invention comprises a system comprising: a master data clock source; one or more transponders; and a plurality of remote power line transceivers; wherein all of said plurality of transceivers are connected to a common alternating current power distribution grid; and wherein each of said plurality of transceivers has a location is operable to monitor a voltage waveform of a power line prevailing at said location. In another aspect, the invention comprises a system comprising: transponders and remote power line transceivers each connected to a common alternating current power distribution grid each operable to monitor the voltage waveform of the power line prevailing at its own location, and generate selectable frequencies from said local power line waveform of a frequency of p/q times the frequency of said power line where p and q are positive integers greater than or equal to 1. | 01-26-2012 |
| 20120056653 | DIGITAL PHASE-LOCKED LOOP - Apparatus, systems and methods are provided for digital phase-locked loops. A digital phase-locked loop comprises an oscillator module configured to generate an output signal and a phase detection module coupled to the oscillator module. The phase detection module is configured to signal the oscillator module to adjust a frequency of the output signal by a first amount when a phase difference between a reference signal and the output signal is less than a threshold amount, and signal the oscillator module to adjust the frequency by a greater amount when the phase difference is greater than the threshold amount. | 03-08-2012 |
| 20120056654 | PHASE LOCKED LOOP CIRCUIT INCLUDING AUTOMATIC FREQUENCY CONTROL CIRCUIT AND OPERATING METHOD THEREOF - Provided is a PLL circuit including automatic frequency control circuit and an operating method thereof. The voltage controlled oscillator is primarily controlled by an automatic frequency control circuit, and is secondarily controlled by a loop filter. The voltage controlled oscillator outputs a coarsely-tuned oscillation signal when primarily controlled, and outputs a finely-tuned oscillation signal when secondarily controlled. The PLL circuit can have a quick frequency fixing time, and output the oscillation signal having a broad and stable frequency. Moreover, the noise characteristic of the PLL circuit is enhanced. | 03-08-2012 |
| 20120062296 | TIME TO DIGITAL CONVERTER AND ALL DIGITAL PHASE-LOCKED-LOOP - According to one embodiment, a multiphase circuit, a flip-flop, and a decoder are provided. The multiphase circuit generates multiphase signals of which phases are different from each other by 180/M degrees by dividing a differential oscillation signal by M (M is an integral number not smaller than 2). The flip-flop captures the multiphase signal in synchronization with an input of a reference signal. The decoder decodes an output signal of the flip-flop. | 03-15-2012 |
| 20120062297 | PHASE LOCKED LOOP (PLL) BASED FREQUENCY SWEEP GENERATOR - A phase locked loop (PLL) based frequency sweep generator and methods for performing a frequency sweep are disclosed. In one implementation, the frequency sweep generator includes a circuit configured to generate a signal having a saw-tooth wave frequency ramp. The saw-tooth wave frequency ramp includes a rising portion and a resetting portion. The resetting portion has a shorter duration than the rising portion and includes a plurality of steps for decrementing the frequency of the signal. | 03-15-2012 |
| 20120092053 | ADAPTIVE CLOCK SWITCHING TO CAPTURE ASYNCHRONOUS DATA WITHIN A PHASE-TO-DIGITAL CONVERTER - A Phase-to-Digital Converter (PDC) within a Phase-Locked Loop (PLL) includes a PDC portion and a PDC decoder portion. The PDC portion receives a reference signal FR and a feedback signal FV and generates therefrom a stream of multi-bit digital values. Each multi-bit value is indicative of a time difference between an edge of FR and a corresponding edge of FV. The PDC decoder portion includes sequential logic elements that are clocked to capture the multi-bit digital values. In order to prevent metastability, the timing of when the sequential logic elements are clocked to capture the multi-bit digital values is adjusted as a function of the phase difference between FR and FV. In one specific example, if the phase difference is small then the falling edge of FR is used to clock the sequential logic elements, whereas if the phase difference is large then the rising edge of FR is used. | 04-19-2012 |
| 20120133405 | PLL START-UP CIRCUIT - A start-up circuit for a PLL includes a phase-frequency detector (PFD), one or more logic gates, a flip-flop and a false detection circuit. The false detection circuit includes a set of series connected flip-flops. The PFD receives a reference signal and a feedback signal. The PFD compares the frequency of a reference signal with that of a feedback signal. If the frequency of the reference signal is greater than the frequency of the feedback signal then a start-up signal is generated and transmitted to the PLL. The PLL increases the frequency of the feedback signal until it is greater than the frequency of the reference signal. The generation of the start-up signal is halted when the frequency of the feedback signal is greater than the frequency of the reference signal. | 05-31-2012 |
| 20120154003 | SPUR REDUCTION TECHNIQUE FOR SAMPLING PLL'S - Control circuitry and method of controlling for a sampling phase lock loop (PLL). By controlling the duty cycle of a sampling control signal, in accordance with the PLL reference and output signals, spurious output signals from the sampling PLL being controlled can be reduced. | 06-21-2012 |
| 20120161838 | MULTI-OUTPUT PLL OUTPUT SHIFT - Controlling a PLL includes providing a voltage controlled oscillator (VCO) and coupling an output of the VCO to a shifter circuit. The shifter circuit has a shifter circuit output, the shifter circuit also including an activation input for receiving an activation signal, the shifter circuit causing at least one pulse of the output signal to be suppressed at the shifter output upon receipt of the activation signal. Controlling also includes coupling the shifter circuit output to a first frequency divider. | 06-28-2012 |
| 20120229185 | Time-to-Digital Converter with Successive Measurements - The invention relates to the conversion into digital information of the time difference between a first signal and a second signal. In particular, in order to determine a fractional part of the number of periods of a first signal for a period of a second signal, the following are alternately performed: /1/ delaying the second signal relative to the first signal and determining a first digital information item, a function of the fractional part, /2/ delaying the first signal relative to the second signal and determining a second digital information item, a function of the fractional part. Then the fractional part is calculated as a function of the previously obtained first and second digital information items. | 09-13-2012 |
| 20120235721 | DIGITAL LOCKED LOOPS AND METHODS WITH CONFIGURABLE OPERATING PARAMETERS - A locked loop may have an adjustable hysteresis and/or a tracking speed that can be programmed by a user of an electronic device containing the locked loop or controlled by an integrated circuit device containing the locked loop during operation of the device. The looked loop may include a phase detector having a variable hysteresis, which may be coupled to receive a reference clock signal and an output clock signal from a phase adjustment circuit through respective frequency dividers that can vary the rate at which the phase detector compares the phase of the output clock signal to the phase of the reference clock signal, thus varying the tracking speed of the loop. The hysteresis and tracking speed of the locked loop may be programmed using a variety of means, such as by a temperature sensor for the electronic device, a mode register, a memory device command decoder, etc. | 09-20-2012 |
| 20120242386 | DIGITAL PLL CIRCUIT AND CLOCK GENERATING METHOD - A digital PLL circuit includes: a digital phase comparator to detect a phase difference between a master clock and a slave clock and output a phase difference detection value; a correction circuit to correct the phase difference detection value to a phase value in accordance with a comparison result between the phase difference detection value and a threshold; and a slave clock generation circuit to generate the slave clock in accordance with the phase value. | 09-27-2012 |
| 20120249200 | DIGITALLY CONTROLLED DELAY LINES WITH FINE GRAIN AND COARSE GRAIN DELAY ELEMENTS, AND METHODS AND SYSTEMS TO ADJUST IN FINE GRAIN INCREMENTS - 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. | 10-04-2012 |
| 20120319750 | MULTI-PART CLOCK MANAGEMENT - An improved approach is described for implementing a clock management system. A multi-part phase locked loop circuit is provided to handle the different clock needs of the circuit, where each of the phase locked loops within the multi-part phase locked loop circuit may feed a clock output to one or more divider circuits. The divider circuits may be dedicated to specific components. For example, a SoC PLL may generate a clock output to a SoC divider that is dedicated to providing a clock to content address memory (CAM) components. This approach allows the clock management system to efficiently generate clock signals with variable levels of frequencies, even for complicated circuits having many different functional portions and components. | 12-20-2012 |
| 20120326759 | REFERENCE QUANTITY GENERATOR - A reference quantity generator for generating a reference quantity includes a reference source configured to provide a reference source signal, a digitally controlled signal source and a digital controller. The digitally controlled signal source is configured to provide a digitally controlled quantity. The reference quantity is determined based on the digitally controlled quantity. The digital controller is configured to provide a digital control signal to control the digitally controlled signal source to adapt the digitally controlled quantity based on the reference source signal using a feedback. | 12-27-2012 |
| 20130043920 | DIGITAL PHASE-LOCKED LOOP APPARATUS USING FREQUENCY SHIFT KEYING AND METHOD OF CONTROLLING THE SAME - A digital phase-locked loop apparatus using FSK includes a PFD detecting phase differences between a reference clock and a frequency-divided signal, and a first adder for generating first digital control codes by adding first digital codes, second digital codes, and channel frequency codes including channel information to each other, the first digital codes being converted from time differences between first and second pulses. The apparatus further includes a digital filter correcting errors of the first digital control codes to generate second digital control codes, a DCO for varying an oscillating frequency in accordance with a digital tuning word based on the second digital control codes, and a dual modulus division unit dividing the oscillating frequency into a frequency-divided signal. | 02-21-2013 |
| 20130049832 | CLOCK GENERATOR WITH DUTY CYCLE CONTROL AND METHOD - A clock generator circuit for producing a clock output having a controlled duty cycle is disclosed. A bi-stable circuit provides the clock output which is switchable to a first state in response to an edge of the input clock signal and to a second state in response to a feedback signal. A duty cycle detection circuit is configured to source a current to a node and to sink a current from the node depending upon the output clock state. A capacitor is connected to receive a duty cycle current relating to the current at the node, with a comparator circuit being configured to sense a voltage on the capacitor and to produce the feedback signal when the voltage is at a selected level. | 02-28-2013 |
| 20130076415 | PLL USING INTERPOLATIVE DIVIDER AS DIGITALLY CONTROLLED OSCILLATOR - One or more PLLs are formed on an integrated circuit. Each PLL includes an interpolative divider configured as a digitally controlled oscillator, which receives a reference clock signal and supplies an output signal divided according to a divide ratio. A feedback divider is coupled to the output signal of the interpolative divider and supplies a divided output signal as a feedback signal. A phase detector receives the feedback signal and a clock signal to which the PLL locks. The phase detector supplies a phase error corresponding to a difference between the clock signal and the feedback signal and the divide ratio is adjusted according to the phase error. | 03-28-2013 |
| 20130154703 | Method and System to Measure and Compensate undue DCO Frequency Peaks at GFSK Ramp Down - One embodiment of the invention relates to a communication system having an amplitude modulation path, a frequency deviation component, a characterization component, a peak cancellation component and a compensation unit. The amplitude modulation path is configured to provide an amplitude modulation signal. The frequency deviation component is configured to generate a frequency deviation signal. The characterization component is configured to generate characterization coefficients according to the amplitude modulation signal and the frequency deviation signal. The peak cancellation component is configured to identify peaks according to the amplitude modulation signal and generate a peak cancellation signal to compensate for peak distortion by the identified peaks. The compensation unit utilizes the characterization coefficients, the amplitude modulation signal and the peak cancellation signal to generate a correction signal that compensates for peak distortions and amplitude modulation to frequency modulation effects. | 06-20-2013 |
| 20130181757 | Method and Device for Clock Recovery - A method and a device for processing a signal determine a timing phase over an observation interval of an input signal. A frequency estimation is determined based on the timing phase. A phase correction is determined for the observation interval based on the timing phase and the frequency offset. Then the phase correction is used to adjust the timing of the input signal. Also, a communication system with at least one such device is described. | 07-18-2013 |
| 20130187693 | FULL-DIGITAL CLOCK CORRECTION CIRCUIT AND METHOD THEREOF - The present invention provides a full-digital clock duty cycle correction circuit and a method thereof. The circuit comprises a sampling unit, a duty cycle correcting module, and a phase-lock module. The duty cycle correcting module produces a first clock signal according to an input clock signal. The phase-lock module produces a second clock signal according to the first clock signal and is used for aligning the positive edges of the clock signals. The duty cycle correcting module adjusts the pulse width of the first clock signal according to the clock signals. In addition, after the pulse width is adjusted, the positive edges of the clock signals are re-aligned. When the pulse width is not equal to zero, the pulse width is re-adjusted and the positive edges are re-aligned until the pulse widths of the clock signals are identical. Finally, the second clock signal is outputted and thus producing a clock signal having 50% duty cycle. | 07-25-2013 |
| 20130187694 | DIGITAL RE-SAMPLING APPARATUS USING FRACTIONAL DELAY GENERATOR - Disclosed herein is a digital re-sampling apparatus. The digital re-sampling apparatus includes a sample buffer, a sample buffer control unit, a filter bank, a first delay bank, a fractional delay constant table, a combiner bank, and a second delay bank. The sample buffer temporarily stores an input sample in synchronization with an input sampling frequency. The sample buffer control unit controls writing and reading operations. The filter bank includes a number of digital filters equal to the number of stages, and filters the input sample. The first delay bank differentially delays a filter output value. The fractional delay constant table stores information about re-sampling time. The combiner bank includes a number of adders and multipliers, performs an operation, and outputs a re-sampled value. The second delay bank causes a delay so that output of each combiner can be synchronized with each output of the fractional delay constant table. | 07-25-2013 |
| 20130249610 | SEMICONDUCTOR DEVICE AND CONTROL METHOD FOR SEMICONDUCTOR DEVICE - A semiconductor device includes: a frequency setting information storage unit that stores sets of frequency information indicating setting of a frequency supplied by an oscillation unit and frequency identification information identifying the frequency information and outputs one of a plurality of pieces of the frequency information to the oscillation unit based on frequency identification information inputted thereinto; a speed setting information storage unit that stores speed identification information indicating a speed of the semiconductor device and frequency identification information corresponding to the speed identification information; a frequency identification information count unit that holds a value of the frequency identification information inputted into the frequency setting information storage unit; and a control unit that causes the frequency identification information count unit to increment or decrement the held value of the frequency identification information to approach a value of the frequency identification information stored in the speed setting information storage unit. | 09-26-2013 |
| 20130249611 | APPARATUS, SYSTEM, AND METHOD FOR CONTROLLING TEMPERATURE AND POWER SUPPLY VOLTAGE DRIFT IN A DIGITAL PHASE LOCKED LOOP - Described herein are apparatus, system, and method for controlling temperature drift and/or voltage supply drift in a digital phase locked loop (DPLL). The apparatus comprises a DPLL including a digital filter to generate a fine code for controlling a frequency of an output signal of a digital controlled oscillator (DCO) of the DPLL; a logic unit to monitor the fine code and to generate a compensation signal based on the fine code; and a voltage adjustment unit to update a power supply level to the DCO based on the compensation signal, wherein the updated power supply level to cause the digital filter to generate the fine code near the middle of an entire range of the fine code across various temperatures, and wherein the digital filter to generate the fine code near the middle of the entire range across power supply drift. | 09-26-2013 |
| 20130271194 | DIGITAL DELAY-LOCKED LOOP WITH DRIFT SENSOR - Embodiments of the present disclosure provide methods, systems, and apparatuses related to an open-loop digital delay-locked loop having a drift sensor. Other embodiments may be described and claimed. | 10-17-2013 |
| 20130278311 | PHASE-FREQUENCY DETECTION METHOD - The present invention relates to a method and device for phase-frequency detection in a phase-lock loop circuit. The method comprises receiving compare edge of a reference clock signal and compare edge of a feedback clock signal, maintaining a phase/frequency detector, PFD, state machine with three PFD states, UP, DOWN, and IDLE, based on the received compare edges of the reference and feedback clock signals, recording current and previous time the state machine stays in UP or DOWN states, generating an UP or DOWN signal based on transition of PFD states and the comparison between recorded current time and recorded previous time; and outputting a digital control signal to a feedback frequency control device based on the UP or DOWN signal. A device and system is arranged to execute the method according to the present invention. | 10-24-2013 |
| 20130285724 | CLOCK GENERATOR FOR GENERATING OUTPUT CLOCK HAVING NON-HARMONIC RELATIONSHIP WITH INPUT CLOCK AND RELATED CLOCK GENERATING METHOD THEREOF - A clock generator has an oscillator block and an output block. The oscillator block provides a second clock of multiple phases, and includes an oscillator and a delay locked loop (DLL). The oscillator is used to provide a first clock. The DLL is used to generate the second clock according to the first clock. The output block is used to receive the second clock and generate a third clock by selecting signals from the multiple phases, wherein the third clock has non-harmonic relationship the first clock. | 10-31-2013 |
| 20130300476 | LOW NOISE AND LOW POWER VOLTAGE CONTROLLED OSCILLATORS - LC tank and ring-based VCOs are disclosed that each include a differential pair of transistors for steering a tail current generated by a current source responsive to a bias voltage. A biasing circuit generates the bias voltage such that a transconductance for the transistors in the differential pairs is inversely proportional to a resistance. | 11-14-2013 |
| 20130300477 | SEMICONDUCTOR DEVICE - A semiconductor device includes a controlled oscillator and a control unit. The controlled oscillator includes a resonance circuit, an amplification unit, and a current adjustment unit. The resonance circuit includes one or a plurality of inductors and a first capacitive unit having a variable capacitance value. The amplification unit is connected to the resonance circuit, and outputs a local oscillation signal having an oscillation frequency corresponding to a resonance frequency of the resonance circuit. The current adjustment unit adjusts a value of a drive current to be supplied to the amplification unit. The control unit controls the capacitance value of the first capacitive unit and the current adjustment unit. When the control unit instructs the current adjustment unit to change the value of the drive current to be supplied to the amplification unit, the control unit also changes the capacitance value of the first capacitive unit. | 11-14-2013 |
| 20130321051 | DIGITAL LOCKED LOOP FOR PRODUCING A CLOCK HAVING A SELECTED FREQUENCY RATIO RELATIVE TO A CLOCK PRODUCED BY A MEMS-BASED OSCILLATOR - A Micro Electrical Mechanical System (MEMS) oscillator supplies a MEMS clock signal to a digital locked loop that generates an output clock signal having a frequency that corresponds to a desired frequency ratio between the MEMS oscillator output signal and the digital locked loop output signal. The frequency ratio may be determined, at least in part, as a function of temperature. | 12-05-2013 |
| 20130328603 | CURRENT OUTPUT CONTROL DEVICE, CURRENT OUTPUT CONTROL METHOD, DIGITALLY CONTROLLED OSCILLATOR, DIGITAL PLL, FREQUENCY SYNTHESIZER, DIGITAL FLL, AND SEMICONDUCTOR DEVICE - A current output control device is provided that includes: a current cell array section including plural current cell circuits that are each connected in parallel between a first terminal (power source) and a second terminal (ground) that connect between the first terminal and the second terminal in by operation ON so as to increase control current flowing between the first terminal and the second terminal; and a code conversion section (decoder) that generates signals (row codes, column codes) to ON/OFF control current cells so as to change the number of current cells that connect the first terminal and the second terminal according to change in an externally input code and that inputs the generated signals to the current cell array section. | 12-12-2013 |
| 20130328604 | CLOCK GENERATOR AND SYSTEM INCLUDING THE SAME - A clock generator includes a digitally controlled oscillator configured to generate an output clock haying a frequency depending on an input code; phase comparison section configured to output a phase differences signal by comparing a reference phase with a phase of the output clock, the reference phase being based on an input clock and a predetermined frequency multiplication number; low-pass filter configured to provide the input code for the digitally controlled oscillator by filtering the phase difference signal; a waveform generating section configured to generate a predetermined spread spectrum wave, the predetermined spread spectrum wave being to be added with both of the frequency multiplication number and the input code; and a detection/compensation section configured to compensate the input code so that the phase difference is reduced, the phase difference being detected from the phase difference signal. | 12-12-2013 |
| 20140021991 | Digital Phase Locked Loop Circuits - Designs of devices having digital phase locked loop (DPLL) circuits that include multiple digital feedback loops to generate high frequency clock signals by a digitally controlled oscillator (DCO). A time-to-digital converter (TDC) module is provided in such a DPLL circuit to receive an input reference clock signal and a first feedback clock signal from a first digital feedback loop and produces a digital TDC output indicative of a first phase error caused by a difference in time between the input reference clock signal and the first feedback clock signal. A second digital feedback loop is provided to generate a second digital feedback signal indicative of a second phase error caused by a difference in frequency between a desired clock signal and a generated clock signal generated by the DCO. The first and second digital feedback loops are coupled to the DCO to generate the high frequency clock signals. | 01-23-2014 |
| 20140021992 | Digital Phase Locked Loop with Feedback Loops - Designs of devices having digital phase locked loop (DPLL) circuits that include multiple digital feedback loops to generate high frequency clock signals by a digitally controlled oscillator (DCO). A time-to-digital converter (TDC) module is provided in such a DPLL circuit to receive an input reference clock signal and a first feedback clock signal from a first digital feedback loop and produces a digital TDC output indicative of a first phase error caused by a difference in time between the input reference clock signal and the first feedback clock signal. A second digital feedback loop is provided to generate a second digital feedback signal indicative of a second phase error caused by a difference in frequency between a desired clock signal and a generated clock signal generated by the DCO. The first and second digital feedback loops are coupled to the DCO to generate the high frequency clock signals. | 01-23-2014 |
| 20140035641 | DUAL MODE PHASE DETECTION - 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. | 02-06-2014 |
| 20140077852 | DELAY LINE OFF-STATE CONTROL WITH POWER REDUCTION - A method and apparatus is provided for controlling a delay line for achieving power reduction. The device comprises a delay lock loop to provide an output signal based upon a phase difference between a reference signal and a feedback signal, said delay lock loop comprising at least one delay circuit comprising a plurality of logic gates configured to provide for substantially uniform degradation of a plurality of NAND gates in a static state. | 03-20-2014 |
| 20140084978 | Digitally Controlled Oscillator with Thermometer Sigma Delta Encoded Frequency Control Word - Systems and methods for generating a thermometer sigma delta encoded frequency control word for controlling a digitally controlled oscillator in accordance with embodiments of the invention are disclosed. In one embodiment, an all digital phase locked loop for generating an output clock signal includes a thermometer pulse coder configured to generate a frequency control word (FCW) that includes thermometer coded signals and a pulse modulated dither signal, and transmit the pulse modulated dither signal over a selected FCW signal line and transmit the thermometer coded signals over other FCW signal lines, and a digitally controlled oscillator to receive a FCW comprising a combined thermometer and pulse modulated signal and generate an output clock signal. | 03-27-2014 |
| 20140103977 | Use of Frequency Addition in a PLL Control Loop - A method and system is disclosed in which the phase detector in a phase-locked loop is able to run at the fastest speed appropriate for a reference signal. A frequency offset is added, to the output frequency of the phase-locked loop, to alter the frequency fed to the frequency divider which would receive the output frequency in a conventional PLL to an intermediate frequency. The frequency offset is selected so that the ratio of the intermediate frequency to the reference frequency is a simple fraction, and preferably an integer, i.e., the intermediate frequency is a multiple of the reference frequency. In cases where the relationship between the output frequency and the reference frequency is largely relatively prime, the phase detector is thus able to receive signals at the frequency of the reference signal and operate at the fastest speed appropriate for the reference signal. | 04-17-2014 |
| 20140132320 | LOSS OF LOCK DETECTOR FOR CLOCK AND DATA RECOVERY SYSTEM - An apparatus comprises a clock and data recovery system, and a loss of lock detector at least partially incorporated within or otherwise associated with the clock and data recovery system. The loss of lock detector is configured to generate a loss of lock signal responsive to phase adjustment requests generated for a clock signal in the clock and data recovery system. By way of example, the loss of lock signal may have a first logic level indicative of the phase adjustment requests occurring at a first rate associated with a lock condition and a second logic level indicative of the phase adjustment requests occurring at a second rate lower than the first rate. Absolute values of respective phase increments each associated with multiple up and down phase requests may be accumulated, and the loss of lock signal generated as a function of the accumulated phase increment absolute values. | 05-15-2014 |
| 20140132321 | IMPLEMENTING COMPACT CURRENT MODE LOGIC (CML) INDUCTOR CAPACITOR (LC) VOLTAGE CONTROLLED OSCILLATOR (VCO) FOR HIGH-SPEED DATA COMMUNICATIONS - A method and a phase locked loop (PLL) circuit for implementing compact current mode logic inductor capacitor voltage controlled oscillator for high speed communications, and a design structure on which the subject circuit resides are provided. The PLL circuit includes a current mode logic (CML) inductor capacitor (LC) Voltage Controlled Oscillator (VCO). The PLL circuit includes a reference circuit generates a virtual ground node for biasing noise sensitive components, providing level shifted VCO increment and decrement tuning values from a phase detector coupled by a respective resistor to tune a varactor of the LC VCO, and providing a loop filter function. The virtual ground node tracks a logic power supply noise, incurring no jitter penalty, and eliminating the need for a separate power supply for the PLL circuit. | 05-15-2014 |
| 20140145771 | DELAY LOCKED LOOP - A circuit includes a delay line and a delay locked loop. The circuit is configured to receive a delay parameter and a clock signal. The delay locked loop is configured to generate a pair of control codes based on a frequency of the clock signal and a frequency of an oscillator of the delay locked loop. The delay locked loop is configured to determine a difference between the frequency of the clock signal and the frequency of the oscillator based on a phase of an output of the oscillator and a phase of the clock signal after the output of the oscillator and the clock signal are aligned. The delay line is configured to receive an input signal and generate an output signal delayed from the input signal by a time delay that corresponds to a delay line control code calculated from the pair of control codes and the delay parameter. | 05-29-2014 |
| 20140159790 | NUMERICALLY CONTROLLED OSCILLATOR AND DIGITAL PHASE-LOCKED LOOP - A digital phase-locked loop is provided. The digital phase-locked loop includes: a phase-locked loop, for generating an output frequency according to a reference frequency; and a numerically-controlled oscillator, coupled to the phase-locked loop, for generating the reference frequency, in which the numerically-controlled oscillator includes: a phase accumulator (PA), for outputting a sawtooth signal according to a clock signal and a frequency control word; and a most significant bit (MSB) detector, coupled to the phase accumulator, for detecting a most significant bit of the sawtooth signal outputted from the phase accumulator, thereby generating the reference frequency with a square waveform. | 06-12-2014 |
| 20140210532 | Phase-Locked Loop Apparatus and Method - A PLL includes an oscillator, a time-to-digital converter (TDC) and a system for the remaining functionality. The TDC measures the oscillator's phase against a reference clock. The measured phase has an integer part obtained from a modulus-K counter, and a fractional part measured by a fine TDC. The system compares the measured phase with a desired phase, and filters it to obtain a parameter that controls the oscillator frequency. The TDC may also include a synchronization block to align the fine TDC and a pulse hider to reduce the power used by the fine TDC. The system may include an integrator to calculate the integer part of the desired phase, a second integrator to calculate the fractional part, and an interpolator for an even finer fraction. A method to obtain fast lock includes using the phase error rate of change to control the oscillator frequency. | 07-31-2014 |
| 20140218085 | PHASE COORDINATING SYSTEMS AND METHODS - Fast phase coordinating systems and methods are disclosed. An example system includes a phase locator configured to detect a first phase of a reference signal and a first phase of a coordinating signal after the first phase of the reference signal. An integrator is configured to integrate from the first phase of the reference signal to a location phase of the coordinating signal and integrate oppositely from the first phase of the coordinating signal to a time-shifted phase of the reference signal and output the result. A control function is configured to shift the phase of the coordinating signal in response to output from the integrator. | 08-07-2014 |
| 20140218086 | METHODS AND DEVICES FOR MULTIPLE-MODE RADIO FREQUENCY SYNTHESIZERS - Methods and devices provide for determining whether to operate a radio frequency synthesizer in a first mode of operation or a second mode of operation based on a reference frequency signal. The radio frequency synthesizer includes a digitally-controlled oscillator configured to generate an oscillator signal having an output frequency. A digital frequency locked-loop is configured to control the output frequency of the oscillator signal in a first mode of operation based on a first control signal. A digital phase locked-loop is configured to control the output frequency of the oscillator signal in a second mode of operation based on a second control signal. A controller determines whether to operate in the first mode or second mode based on a reference frequency signal. The controller generates the first or second control signal based on the determination of operating in the first or second mode, respectively. | 08-07-2014 |
| 20140266353 | MIXED SIGNAL TDC WITH EMBEDDED T2V ADC - A time-to-digital converter converts the difference between transition times of a reference clock signal and an oscillating signal to a digital signal whose value is proportional to the transitions timing difference. The time-to-digital converter includes an edge detector, a time-to-voltage converter, and an analog-to-digital converter. The edge detector is adapted to detect, during each period of the reference clock signal, the edge (transition) of the oscillating signal that is closest to the edge of the reference clock signal. The time-to-voltage converter is adapted to generate an analog signal proportional to a difference in time between the detected edge of the oscillating signal and the edge of the reference clock signal. The analog-to-digital converter is adapted to convert the analog signal to a digital signal whose value is proportional the difference between the occurrence of the detected edge of the oscillating signal and the edge of the reference clock signal. | 09-18-2014 |
| 20140266354 | DIGITAL PHASE-LOCKED LOOP - Disclosed is a digital phase-locked-loop including: a time-to-digital converter (TDC) configured to output a digital bit based on an input clock and a reference clock, in which the TDC includes: a first arbiter group configured to compensate for a phase difference between the input clock and the reference clock with a first average offset and output a first logic value; a second arbiter group configured to compensate for a phase difference between the input clock and the reference clock with a second average offset and output a second logic value; and a signal processor configured to output the digital bit based on the first and second logic values. | 09-18-2014 |
| 20140266355 | PHASE-LOCKED LOOP, METHOD OF OPERATING THE SAME, AND DEVICES HAVING THE SAME - A method of operating a phase-locked loop (PLL) such as an all-digital PLL includes operations of comparing a reference clock signal with a feedback signal of the PLL and outputting a comparison signal according to a result of the comparison, and detecting whether the PLL is in a lock state by using a number of times the comparison signal is toggled. | 09-18-2014 |
| 20140320186 | PHASE LOCKED LOOP WITH PRECISE PHASE AND FREQUENCY SLOPE LIMITER - Phase slope is controlled in a phase locked loop wherein a phase error signal controlling a controlled oscillator has a proportional component and an integral component, by determining whether the proportional component falls within a range bounded by upper and lower limit values. The proportional component is combined with the integral component if the proportional component falls within the range to provide the phase error signal. Otherwise, the proportional component is modified to meet a phase slope requirement while leaving the integral component unmodified. The modified proportional component is combined with the unmodified integral component to provide the phase error signal. | 10-30-2014 |
| 20140333358 | RE-CIRCULATING TIME-TO-DIGITAL CONVERTER (TDC) - A re-circulating time-to-digital converter (TDC) can include a triggered reference ring oscillator (TRRO) and a delay module. The triggered reference ring oscillator can, when triggered by a reference signal edge, generate a periodic ring oscillator signal with a ring oscillator period that is a selected ratio of a voltage-controlled oscillator (VCO) period. The delay module can store, in a plurality of latches, samples of a VCO signal docked by the periodic ring oscillator signal. Each latch can generate an output of the sample, and each latch output can represent a time difference polarity between VCO signal and TRRO signal. In another example, the re-circulating TDC can include the triggered reference ring oscillator, a digital frequency lock module, and a TDC post-process module. The digital frequency lock module can generate a ring oscillator control signal, which sets the ring oscillator period for the triggered reference ring oscillator. The TDC post-process module can generate a TDC output, which can be a binary representation of a phase difference between a reference signal and a VCO signal. | 11-13-2014 |
| 20140333359 | APPARATUSES AND METHODS FOR DELAYING SIGNALS USING A DELAY LINE WITH HOMOGENOUS ARCHITECTURE AND INTEGRATED MEASURE INITIALIZATION CIRCUITRY - Apparatuses and methods for delaying signals using a delay line are described. An example apparatus includes a controller configured to in a first mode, set a delay length, and, in a second mode, to determine an initial delay. The apparatus further including a delay line circuit coupled to the controller and includes delay elements. Each of the delay elements includes delay gates that are the same type of delay gate. The delay line circuit is configured to, in the first mode propagate a signal through one or more of the delay elements to provide a delayed signal. The delay line circuit is further configured to, in the second mode, propagate a pulse signal through one or more of the delay elements and provide a corresponding output signal from each of the one or more delay elements responsive to the pulse signal reaching an output of the corresponding delay element. | 11-13-2014 |
| 20140347109 | HYBRID PHASE-LOCKED LOOPS - A circuit may include an oscillator configured to generate an output signal based on an analog signal and a digital signal and a controller configured to generate an offset signal based on a comparison of a first analog control signal and a second analog control signal. The circuit may also include a divider configured to generate a feedback signal based on the output signal and the offset signal. The circuit may also include an analog control signal unit configured to generate the second analog control signal based on the feedback signal and a reference signal and a coupling unit configured to select either the first analog control signal or the second analog control signal as the analog signal. | 11-27-2014 |
| 20140347110 | CAPACITIVE LOAD PLL WITH CALIBRATION LOOP - A circuit includes a capacitive-load voltage controlled oscillator having an input configured to receive a first input signal and an output configured to output an oscillating output signal. A calibration circuit is coupled to the voltage controlled oscillator and is configured to output one or more control signals to the capacitive-load voltage controlled oscillator for adjusting a frequency of the oscillating output signal. The calibration circuit is configured to output the one or more control signals in response to a comparison of an input voltage to at least one reference voltage. | 11-27-2014 |
| 20150028926 | DIGITALLY CONTROLLED OSCILLATOR DEVICE AND HIGH FREQUENCY SIGNAL PROCESSING DEVICE - The present invention provides a digitally controlled oscillator device capable of realizing a reduction in DNL. The digitally controlled oscillator device includes, for example, an amplifier circuit block, coil elements and a plurality of unitary capacitor units coupled in parallel between oscillation output nodes. Each of the unitary capacitor units is provided with capacitive elements, and a switch which selects whether the capacitive elements should be allowed to contribute as set parameters for an oscillation frequency. The switch is driven by an on/off control line extending from a decoder circuit. The on/off control line is shielded between the oscillation output nodes by a shield section. | 01-29-2015 |
| 20150077165 | METHOD AND APPARATUS FOR AVOIDING SPURS IN CHIP - A method is for rejecting spurs within a chip containing analog and digital functions. The spurs may be timed by a clock signal derived from the output frequency of a high frequency phase locked loop. Original analog rejection bandwidths associated with operation of analog functions may be determined, and then original spurs associated with operation of the digital functions and capable of directly or indirectly affecting the original analog rejection bandwidths may be identified. A final analog rejection bandwidth may be determined based on the original analog rejection bandwidths, and final spurs may be obtained based on the original spurs. A frequency shift of the output frequency of the high frequency phase locked loop to effectuate a rejection of the final spurs from the final analog rejection bandwidth may be determined, and the high frequency phase locked loop may be controlled to shift the output frequency by the frequency shift. | 03-19-2015 |
| 20150102845 | Phase Locked Loop - A circuit includes a phase locked loop and a logic IC. The phase locked loop is coupled to the logic IC. The logic IC is configured for generating an adaptive residue according to a first parameter and a second parameter. The phase locked loop is configured for providing the first parameter and the second parameter, and the phase locked loop generates an oscillator signal based on the adaptive residue. | 04-16-2015 |
| 20150116018 | PHASE-LOCKED LOOP CIRCUIT - A phase-locked loop circuit, a phase converter module thereof and a phase-locked controlling method are disclosed herein. The phase converter module is suitable for a phase-locked loop circuit including a digitally-controlled oscillator (DCO) for generating an oscillator output signal and a divider for converting the oscillator output signal into N-phased oscillator output signals. The phase converter module includes a period extender, a phase finder and a time-to-digital converter. The period extender is configured for extending the N-phased oscillator output signals into M*N-phased oscillator output signals corresponding to M oscillation period of the digitally-controlled oscillator. The phase finder is configured for sampling the oscillator output signal with the M*N-phased oscillator output signals to calculate an estimated value of the fractional phase part. The time-to-digital converter is configured to calculate a precise value of the fractional phase part within one sub-period. | 04-30-2015 |
| 20150145571 | CANCELLATION OF DELTA-SIGMA QUANTIZATION NOISE WITHIN A FRACTIONAL-N PLL WITH A NONLINEAR TIME-TO-DIGITAL CONVERTER - A fractional-N phase-locked loop (PLL) includes a nonlinear time to digital converter that generates a digital representation of a phase error corresponding to a time difference between a feedback signal of the fractional-N PLL and a reference signal. A nonlinear quantization noise cancellation circuit supplies a correction signal to ensure that the generated digital representation has reduced quantization noise. The correctional signal may be applied in the analog or digital domain. | 05-28-2015 |
| 20150145572 | TIME-TO-DIGITAL CONVERTER AND PLL CIRCUIT USING THE SAME - A time-to-digital converter (TDC) that has high resolution, excellent linearity, and a widerange. The TDC includes a first oscillator unit that generates and outputs a pair of first oscillation signals based on a pair of predetermined clock signals that have a predetermined phase difference, a second oscillator unit that generates and outputs a second oscillation signal that have a predetermined frequency based on the pair of first oscillation signals outputted from the first oscillator unit, and a quantizer that calculates a quantized value based on a number of edges of the second oscillation signal outputted from the second oscillator unit. | 05-28-2015 |
| 20150311905 | ALL-DIGITAL PHASE-LOCKED LOOP (ADPLL) - An all-digital phase-locked loop (ADPLL) is provided. The ADPLL comprises a first circuit and a second circuit. The first circuit is configured to monitor a first signal and set a voltage of a second signal to a voltage within a first voltage range when a code of fine-tuning is equal to a first specified value. The first circuit is configured to set a voltage of a third signal to a voltage within a second voltage range when the code of fine-tuning is equal to a second specified value. The second circuit is configured to increase a code of coarse-tuning when the voltage of the second signal is within the first voltage range, and decrease the code of coarse-tuning when the voltage of the third signal is within the second voltage range. The ADPLL provides a target frequency despite changes in at least one of process, voltage or temperature. | 10-29-2015 |
| 20150311908 | LOCAL OSCILLATOR INTERFERENCE CANCELLATION - Systems and methods for mitigating interference in a Local Oscillator (LO) signal generated by a Phase-Locked Loop (PLL) are disclosed. In one embodiment, a system includes a PLL and an error compensation subsystem. The PLL includes a Controlled Oscillator (CO) that provides a LO output signal based on a control signal, a phase detector that generates a phase detector output signal that is indicative of a phase error between a feedback signal that is a function of the LO output signal and a reference signal, and a loop filter that filters the phase detector output signal to provide the control signal for the CO. The error compensation subsystem applies, based on the phase detector output signal, a phase rotation to a signal derived from the LO output signal to thereby compensate for a phase error in the signal resulting from a phase error in the local oscillator output signal. | 10-29-2015 |
| 20160013800 | LOW POWER AND COMPACT AREA DIGITAL INTEGRATOR FOR A DIGITAL PHASE DETECTOR | 01-14-2016 |
| 20160020775 | PHASE-LOCKED LOOP (PLL) - A phase-locked loop (PLL) is provided. The PLL comprises a clock adjuster configured to receive an initial clock signal having an initial frequency and a mode control signal. The clock adjuster is configured to modify the initial clock signal into a modified clock signal based on the mode control signal. The PLL is configured such that a loop bandwidth is equal to a specified bandwidth. When the modified clock signal is changed, a loop gain of a loop filter is adjusted such that the loop bandwidth is substantially equal to the specified bandwidth. When the modified clock signal is changed, an oscillator tuning word (OTW) signal is modified into a normalized OTW signal such that the loop bandwidth is substantially equal to the specified bandwidth. | 01-21-2016 |
| 20160049947 | SPREAD SPECTRUM CLOCK GENERATOR - A spread spectrum clock generator includes: a phase comparing unit that receives a reference clock signal and a feedback clock signal, and generates a control voltage corresponding to a phase difference between the reference clock signal and the feedback clock signal; a voltage-controlled oscillator that oscillates at an oscillating frequency corresponding to the control voltage, and generates an output clock signal; a delta-sigma modulator that receives a waveform signal for controlling spreading of a spectrum of the output clock signal, and outputs bits larger than 1 bit based on the waveform signal; a control circuit that controls a multiplication number according to an output signal of the delta-signal modulator; and a divider that generates the feedback clock signal by dividing the output clock signal according to the multiplication number controlled by the control circuit, and supplies the feedback clock signal to the phase comparing unit. | 02-18-2016 |
| 20160065223 | FOREGROUND AND BACKGROUND BANDWIDTH CALIBRATION TECHNIQUES FOR PHASE-LOCKED LOOPS - Certain aspects of the present disclosure support a method and apparatus for foreground and background bandwidth calibration in a frequency-do-digital converter based phase-locked loop (FDC-PLL) device. | 03-03-2016 |
| 20160079992 | SYSTEMS AND METHODS FOR FREQUENCY DOMAIN CALIBRATION AND CHARACTERIZATION - A system for assigning a characterization and calibrating a parameter is disclosed. The system includes a frequency measurement circuit and a finite state machine. The frequency measurement circuit is configured to measure frequencies of an oscillatory signal and to generate a measurement signal including measured frequencies. The finite state machine is configured to control measurements by the frequency measurement circuit, to assign a characterization to a parameter based on the measurement signal, and to generate a calibration signal based on the characterized parameter. | 03-17-2016 |
| 20160156362 | TIME-TO-DIGITAL CONVERTER USING STOCHASTIC PHASE INTERPOLATION | 06-02-2016 |
| 20160191066 | METHOD AND APPARATUS TO SUPPRESS DIGITAL NOISE SPURS USING MULTI-STAGE CLOCK DITHERING - A clock dithering circuit that provides cancellation of digital noise spurs is disclosed. The clock dithering circuit includes a control unit that receives an input clock. An ICG (integrated clock gating) cell receives the input clock and receives an enable signal from the control unit. The ICG cell generates a gated clock. A coarse dither unit receives the gated clock and receives a coarse select signal from the control unit. The coarse dither unit generates a coarse dither clock. A fine dither unit receives the coarse dither clock and receives a fine select signal from the control unit. The fine dither unit generates a fine dither clock. | 06-30-2016 |
| 20160254818 | Phase Locked Loop with Sub-harmonic Locking Prevention Functionality | 09-01-2016 |
