Class / Patent application number | Description | Number of patent applications / Date published |
331175000 | FREQUENCY STABILIZATION | 33 |
20080266011 | Oscillator signal stabilization - An oscillator signal stabilization method is provided for a radio transceiver, for example. In the present stabilization method, amplitude variation of a radio frequency oscillator signal generated by a frequency-adjustable oscillator signal generator is stabilized in an adaptive compensation circuit having adjustable compensation parameters. The stabilized oscillator signal is fed from the compensation circuit to one or more frequency dividers for frequency division. The compensation circuit is configured to stabilize signal variations caused by component non-idealities and, thereby, prevent undesired frequency division errors in the frequency dividers. | 10-30-2008 |
20090058548 | Method and signal control system providing fast transitions in an oscillating signal - In one embodiment, a signal control system has a signal output and includes: 1) a phase-locked loop (PLL) having a voltage-controlled oscillator (VCO), a phase error detector, an oscillating output coupled to the signal output of the signal control system, and a programmable frequency divider coupled in a feedback path between the oscillating output and the phase error detector; 2) at least one automatic level controller (ALC), coupled to the oscillating output; and 3) a plurality of switchable integrators, including first and second switchable integrators that are respectively coupled between the phase error detector and the VCO, and in the at least one ALC. Each of the switchable integrators is switchable between a narrow bandwidth mode that provides for stable operation of the signal control system, and a wide bandwidth mode that enables fast signal transitions at the signal output. | 03-05-2009 |
20090066432 | PLL Circuit and Semiconductor Device Having the Same - A PLL circuit includes a phase detector, a loop filter (LF), a voltage-controlled oscillator (VCO), and a frequency divider. The phase detector compares a phase of a signal Fs which is input from outside with a phase of a signal Fo/N which is input from the frequency divider. The loop filter generates a signal Vin by removing alternating current components from a signal input from the phase detector. The voltage-controlled oscillator outputs a signal Fo based on the signal Vin input from the loop filter. The frequency divider converts the signal Fo output from the voltage-controlled oscillator into Fo/N (frequency division by N), and outputs it to the phase detector. | 03-12-2009 |
20090096542 | FREQUENCY STABILIZING DEVICE OF AN OSCILLATOR - A frequency stabilizing device of an oscillator is disclosed. The frequency stabilizing device of an oscillator is used for stabilizing the frequency of an oscillator to keep the frequency in constant when input voltage is changed. The frequency stabilizing device comprises a plurality of transmission gates for receiving an input voltage and generating a current and a plurality of resistors for control the value of the current, wherein the current is positive in relation to the input voltage and the frequency of the oscillator is determined by the current. | 04-16-2009 |
20090267700 | TIMING OSCILLATORS AND RELATED METHODS - Timing oscillators as well as related methods and devices are described. A timing oscillator may include a mechanical resonating structure with major elements and minor elements coupled to the major element. The timing oscillator can generate stable signals with low phase noise at very high frequencies which allows a timing oscillator to be used effectively in a number of devices including computers and mobile phones for time and data synchronization purposes. The signal generated by the timing oscillator can be tuned using a driver circuit and a compensation circuit. | 10-29-2009 |
20090302962 | ELECTRONIC APPARATUS COMPENSATED THROUGH MONITORING NON-TEMPERATURE FACTOR INDICATIVE OF FREQUENCY DRIFT OCCURRENCE OF REFERENCE CLOCK AND RELATED METHOD THEREOF - In one exemplary implementation, an electronic apparatus has a reference clock source for generating a reference clock, a monitoring circuit for monitoring a non-temperature factor indicative of frequency drift occurrence of the reference clock to thereby generate a monitoring result, and a compensating circuit for compensating the reference clock according to the monitoring result. In another exemplary implementation, an electronic apparatus has a reference clock source for generating a reference clock, a processing logic for performing a designated operation according to the reference clock, a monitoring circuit for monitoring a non-temperature factor indicative of frequency drift occurrence of the reference clock to thereby generate a monitoring result, and a compensating circuit for compensating the designated operation according to the monitoring result. | 12-10-2009 |
20110025427 | ELECTRONIC APPARATUS COMPENSATED THROUGH MONITORING A STATUS OF GNSS RECEIVER AND RELATED METHOD THEREOF - In one exemplary implementation, an electronic apparatus includes: a reference clock source, for generating a reference clock; a global navigation satellite system (GNSS) receiver for receiving satellites signals and the reference clock, comprising: a monitoring circuit, for monitoring a status of the GNSS receiver to generate a monitoring result; and a compensating circuit, coupled to the reference clock source and the monitoring circuit, for compensating the reference clock according to the monitoring result. | 02-03-2011 |
20130027148 | ANTIRESONANT FREQUENCY-VARYING COMPLEX RESONANT CIRCUIT - A complex resonant circuit includes: a first current path performing a first gain control to an AC power signal being supplied; at least one second current path performing a second gain control different from the first gain control to the AC power signal; at least two resonant circuits provided on the respective first and second current paths, having mutually different resonance or antiresonance points for the AC power signals passing through the respective first and second current paths and capturing the respective AC power signals; at least one compensation current path performing a compensation phase shift to the AC power signal; a compensation circuit, provided on the compensation current path, for removing an unnecessary component of the resonant circuit; and an analog operational circuit performing analog addition or subtraction on the AC power signal having passed through the first and second current paths, and the compensation current path. | 01-31-2013 |
20140035690 | VOLTAGE CHANGE COMPENSATION TYPE OSCILLATOR AND METHOD OF COMPENSATING ERROR OF OSCILLATOR - The present invention relates to a voltage change compensation type oscillator and a method of compensating an error of an oscillator, which includes a voltage level detecting unit; a current level adjusting unit; and an oscillating core unit for generating and outputting a clock signal by receiving a power supply voltage and an output current of the current level adjusting unit, wherein the current level adjusting unit adjusts the output current in proportion to an increase of the voltage level detected by the voltage level detecting unit, thus remarkably reducing a frequency error of the clock signal in spite of changes in voltage. | 02-06-2014 |
20140077891 | CRYSTAL OSCILLATOR EMULATOR WITH EXTERNALLY SELECTABLE OPERATING CONFIGURATIONS - A crystal oscillator emulator having a plurality of predetermined operating configurations. The crystal oscillator emulator includes a measurement circuit configured to measure a value of an impedance connected to a select pin of the crystal oscillator emulator, wherein the impedance is external to the crystal oscillator emulator, and generate an output having a value corresponding to the value of the impedance. The storage circuit is configured to store a plurality of values corresponding to the plurality of predetermined operating configurations and select one of the plurality of values based on the output of the measurement circuit. A controller is configured to set an output frequency of the crystal oscillator emulator based on the selected one of the plurality of values. | 03-20-2014 |
331176000 | Temperature or current responsive means in circuit | 23 |
20080231386 | Oscillation circuit and the method for using the same - The oscillation circuit includes an output current mirror, a P-N complementary current mirror, a P-type current mirror and an N-type current mirror. The P-N complementary current mirror has the same structure as the output current mirror but has current that is only 1/k times the current of the output current mirror, wherein k is greater than 1. The P-type current mirror connects to the P-N complementary current mirror, and has current that is m times the current of the P-N complementary current mirror, where m is greater than 1. The N-type current mirror has one end connected to the P-type current mirror and another end connected to the output current mirror. The N-type current mirror has current that is n times the current of the P-type current mirror, where | 09-25-2008 |
20080238562 | VOLTAGE-CONTROLLED OSCILLATOR - A voltage-controlled oscillator has an oscillation frequency controlled through a voltage applied across ends of a variable-capacitance element. The voltage-controlled oscillator has a frequency control bias circuit which applies to a first end of the variable-capacitance element a voltage for frequency control according to a control voltage, a first current source which generates a first current according to the control voltage, a second current source which generates a second current according to temperature, independent of the control voltage, a converting resistor which converts a current, obtained by adding together the first and second currents, into a voltage, and a temperature compensation bias circuit which applies to the second end of the variable-capacitance element a voltage for temperature compensation according to the voltage produced by the converting resistor. | 10-02-2008 |
20080238563 | APPARATUS AND METHOD FOR MEASUREMENT OF TEMPERATURE USING OSCILLATORS - A temperature sensor includes: a first oscillator that generates a first frequency signal; a second oscillator that generates a second frequency signal; a multiplexer that selectively passes the first frequency signal and the second frequency signal; and a frequency-to-digital converter that converts a frequency difference between the first frequency signal and the second frequency signal into a digital code. | 10-02-2008 |
20080297268 | TEMPERATURE-COMPENSATED CRYSTAL OSCILLATOR AND TEMPERATURE COMPENSATION METHOD FOR OSCILLATOR - A temperature-compensated crystal oscillator includes an oscillation circuit including an oscillator, a temperature detector, a voltage variable capacitance element coupled to an oscillation loop of the oscillation circuit, and a temperature compensation circuit. The temperature compensation circuit is configured to apply a compensation voltage to the voltage variable capacitance element to compensate a temperature change in response to temperature data detected by the temperature detector. The temperature compensation circuit has a plurality of correction point data. The respective correction point data is set in advance for each divided temperature zone, selects a first correction point data in a lower temperature zone and a second correction point data in a higher temperature zone, as compared with the detected temperature data, performs an interpolation between the first and second correction point data by a weighted averaged first-order interpolation, and generates the compensation voltage. | 12-04-2008 |
20090002086 | Film bulk acoustic resonator calibration - Film bulk acoustic resonators (FBARS) have resonant frequencies that vary with manufacturing variations, but tend to be matched when in proximity on an integrated circuit die. FBAR resonant frequency is determined using a fractional-N synthesizer and comparing phase/frequency of an output signal from the fractional-N synthesizer to a reference. The reference may be derived from a low frequency crystal oscillator, an external signal source, or a communications signal. | 01-01-2009 |
20090085684 | LOW POWER RTC OSCILLATOR - The integrated circuit package includes a processing core for operating on a set of instructions to carry out predefined processes. An internal oscillator provides a system clock for the integrated circuit package. A programmable load capacitor array provides a programmable load to tune an oscillation frequency of the internal oscillator. An internal oscillator control register for controlling the operation of the programmable load capacitor array responsive to control bits of the programmable load capacitor array controlled by the processing core. | 04-02-2009 |
20090115542 | TEMPERATURE COMPENSATION OSCILLATOR AND METHOD FOR MANUFACTURING THE SAME - A temperature detection circuit ( | 05-07-2009 |
20090128246 | Apparatus and method of temperature compensating an ovenized oscillator - An oscillator having improved frequency stability which includes an oscillator circuit and an SC-cut resonator connected with the oscillator circuit. The SC-cut resonator has a first turning point. A temperature compensation circuit is connected with the oscillator circuit. The temperature compensation circuit is adapted to adjust a reference frequency generated by the oscillator circuit according to a frequency response associated with a second turning point of an AT-cut resonator. | 05-21-2009 |
20090146752 | Clock, Frequency Reference, and Other Reference Signal Generator with a Controlled Quality Factor - Exemplary embodiments of the invention provide a reference signal generator having a controlled quality (“Q”) factor. An exemplary apparatus to generate a harmonic reference signal includes a reference resonator, such as an LC-tank, which generates a first reference signal having a resonant frequency, and a plurality of reactance modules couplable to the reference resonator. Each reactance module comprises one or more reactance unit cells, and each reactance unit cell comprises a reactance element coupled in series to a switching element. In exemplary embodiments, the reactance element is a capacitor having a predetermined unit of capacitance, and the switching element is a transistor having a predetermined resistance when in an off state. The ratio of capacitance to resistance is substantially constant for all reactance modules of the plurality of reactance modules. | 06-11-2009 |
20090160569 | SYSTEMS AND METHODS FOR COMPENSATING FOR VARIATIONS OF THE OUTPUT OF A REAL-TIME CLOCK - Method and systems are provided for adjusting real-time clocks to compensate for frequency offset, temperature effects, and/or aging effects. | 06-25-2009 |
20090167451 | Frequency Controller for a Monolithic Clock Generator and Timing/Frequency Reference - In various embodiments, the invention provides a frequency controller to control and provide a stable resonant frequency of a clock generator and/or a timing and frequency reference. Such stability is provided over variations in a selected parameter such as temperature and fabrication process variations. The various apparatus embodiments include a sensor adapted to provide a signal in response to at least one parameter of a plurality of parameters; and a frequency controller adapted to modify the resonant frequency in response to the second signal. In exemplary embodiments, the sensor is implemented as a current source responsive to temperature fluctuations, and the frequency controller is implemented as a plurality of controlled reactance modules which are selectively couplable to the resonator or to one or more control voltages. The controlled reactance modules may include fixed or variable capacitances or inductances, and may be binary weighted. Arrays of resistive modules are also provided, to generate one or more control voltages. | 07-02-2009 |
20100079214 | Temperature compensation method and apparatus for an output frequency signal based on successive approximation - Techniques of compensating frequency in an output in reference to a reference frequency signal are disclosed. The reference frequency signal may be from a crystal oscillator or other oscillators. Due to the changes of the temperature, the reference frequency signal drifts. According to one aspect of the techniques, a temperature frequency correction word is generated in accordance with a frequency compensation value in view of a current temperature to generate a substantially temperature compensated frequency output from a reference frequency signal. The frequency control word is produced from a successive approximation circuit configured to produce the temperature frequency correction word in accordance with the frequency compensation value in view of the current temperature. Both the temperature frequency correction word and a frequency control word are data represented in a sequence of bits. As a result, the compensated frequency output can be of high precision. | 04-01-2010 |
20100265000 | TEMPERATURE COMPENSATED CRYSTAL OSCILLATOR - A temperature compensated crystal oscillator is mounted to a board. A quartz resonator includes a quartz chip that generates an oscillation frequency. A resistive element is formed on the quartz chip. A temperature sensor is located closer to the board than the quartz resonator. The compensation part compensates for a change in the oscillation frequency generated by the quartz resonator based on a value of a current flowing in the resistive element and an output of the temperature sensor. | 10-21-2010 |
20110121909 | TEMPERATURE COMPENSATION METHOD FOR PIEZOELECTRIC OSCILLATOR, AND PIEZOELECTRIC OSCILLATOR - A temperature compensation method for a piezoelectric oscillator including a piezoelectric vibrator having a frequency temperature characteristic with a hysteresis characteristic, and an oscillation circuit which oscillates the piezoelectric vibrator and outputs an oscillation signal, wherein, to a temperature compensation circuit which can calculate a quantity of temperature compensation using frequency temperature information indicating a temperature characteristic of an oscillation frequency of the piezoelectric vibrator and temperature information of the piezoelectric vibrator at the time of oscillation of the oscillation signal, the oscillation signal and the frequency temperature information are outputted, includes: calculating, as the frequency temperature information, an intermediate value between elevated-temperature frequency temperature information of the piezoelectric vibrator that is generated in the case where ambient temperature of the piezoelectric vibrator is elevated, and lowered-temperature frequency temperature information of the piezoelectric vibrator that is generated in the case where the ambient temperature is lowered. | 05-26-2011 |
20120286890 | TEMPERATURE-COMPENSATED OSCILLATOR AND ELECTRONIC DEVICE - A temperature-compensated oscillator includes a temperature sensor, a temperature compensation circuit, a voltage-controlled oscillation circuit adapted to output an oscillation signal on which temperature compensation is performed based on the temperature compensation voltage, an output circuit adapted to output an ON/OFF signal based on a relationship between variation of the detected-temperature voltage output by the temperature sensor and a reference voltage, a switch circuit adapted to supply the temperature compensation circuit with electrical power in response to the ON/OFF signal, and a sample-and-hold circuit adapted to be switched between a state of outputting the temperature compensation voltage to the voltage-controlled oscillation circuit while holding the temperature compensation voltage output by the temperature compensation circuit, and a state of outputting the temperature compensation voltage held to the voltage-controlled oscillation circuit while cutting the connection to the temperature compensation circuit in response to the ON/OFF signal. | 11-15-2012 |
20120319793 | OSCILLATION CIRCUIT - There is provided an oscillation circuit including: a band-gap circuit that outputs an output voltage adjusted for temperature dependency so as to give a constant output voltage independent of temperature; a voltage-current conversion circuit including a first variable resistor, the voltage-current conversion circuit converting an output voltage output from the band-gap circuit into an output current corresponding to the resistance of the first variable resistor and outputting a bias current based on the converted output current; and a CR oscillation circuit including a second variable resistor, a capacitor and a comparator section, the CR oscillation circuit oscillating with an oscillation frequency based on the resistance of the second variable resistor and the capacitance value of the capacitor, and the CR oscillation circuit operating according to the amperage of the bias current the comparator section has input from the voltage-current conversion circuit. | 12-20-2012 |
20130154753 | Oscillation circuit and oscillation system - An oscillation circuit includes a threshold voltage extraction module, a positive temperature coefficient voltage generation module, an addition module, a common-source amplifier module, a charge and discharge module, and a clock output terminal. The common-source amplifier module includes a first field effect transistor (FET) and a second FET. The addition module includes a first operational amplifier, a second operational amplifier, a third FET, a fourth FET, a fifth FET, a sixth FET, a first resistor, a second resistor, and a third resistor. The charge and discharge module includes a seventh FET, an eighth FET, a charge and discharge FET, a first switch, a second switch, a first comparator, a second comparator, a first nor gate and a second nor gate. An oscillation system is further provided. The oscillation circuit and the oscillation system of the present invention have simple structures and are easy to implement. | 06-20-2013 |
20130314169 | OSCILLATING DEVICE, OSCILLATING ELEMENT AND ELECTRONIC APPARATUS - An oscillating device includes a temperature compensated oscillator that compensates a frequency temperature characteristic in a temperature compensation range including apart of a first temperature range, and a temperature control circuit that includes a heater and controls a temperature of a quartz crystal resonator of the temperature compensated oscillator into a second temperature range included in the temperature compensation range. Further, the temperature compensation range of the temperature compensated oscillator may include a part of the first temperature range in which compensation can be performed by first-order approximation. | 11-28-2013 |
20140049331 | TCXO REPLACEMENT FOR GPS - To determine the level of frequency drift of a crystal oscillator as a result of a change in the its temperature, the temperature of the crystal oscillator is sensed and used together with previously stored data that includes a multitude of drift values of the frequency of the crystal oscillator each associated with a temperature of the crystal oscillator. Optionally, upon initialization of a GPS receiver in which the crystal oscillator is disposed, an initial temperature of the crystal oscillator is measured and a PLL is set to an initial frequency in association with the initial temperature. When acquisition fails in a region, the ppm region is changed. The temperature of the crystal oscillator is periodically measured and compared with the initial temperature, and the acquisition process is reset if there is a significant change in temperature. The GPS processor enters the tracking phase when acquisition is successful. | 02-20-2014 |
20140104012 | OSCILLATOR COMPENSATION CIRCUITS - A system and method is provided for controlling frequency of an oscillator. The system includes two or more temperature sensing circuits configured to generate temperature sensing signals corresponding to temperatures obtained by the two or more temperature sensing circuits. The system also includes a reference signal generation circuit configured to generate a reference signal and a first curve function generation circuit coupled to the two or more temperature sensing circuits and the reference signal generation circuit. The first curve function generation circuit is configured to provide two or more curve-generating signals based on the temperature sensing signals and the reference signal. The system further includes a summing circuit coupled to the first curve function generation circuit. The summing circuit is configured to provide, based on the two or more curve-generating signals, a first signal for controlling the frequency of the oscillator. | 04-17-2014 |
20140218123 | TEMPERATURE COMPENSATION FOR OSCILLATOR - A temperature compensation apparatus may include a sense circuit configured to produce a sense voltage that is dependent on temperature and a temperature compensation circuit configured to receive the sense voltage and produce a temperature compensation control signal to control a compensation capacitor array of an oscillator. The temperature compensation circuit may be configured to calibrate the control signal to have a first value at a first temperature. The temperature compensation circuit may also be configured to calibrate a trimming level (e.g., slope) of the control signal. | 08-07-2014 |
20140247095 | FREQUENCY TEMPERATURE OFFSET COMPENSATION - One embodiment relates to a method of compensating for crystal frequency variation over temperature. An example method includes obtaining an indication of temperature, computing a temperature compensation value based on the indication of temperature and a piecewise linear temperature compensation approximation, and compensating for a temperature offset in a crystal reference signal by adjusting a division ratio of a fractional divider in a phase-locked loop. The piecewise linear temperature compensation approximation can represent an approximation of frequency error in a crystal reference signal originating from a crystal over temperature. The piecewise linear temperature compensation approximation can be, for example, a linear approximation, a quadratic approximation, or a cubic approximation. | 09-04-2014 |
20150028960 | OSCILLATOR - An oscillator uses a differential signal corresponding to a difference between an oscillation output f1 of a first oscillator circuit and an oscillation output f2 of a second oscillator circuit as a temperature detection value, and outputs a control signal for reducing an influence caused by a temperature characteristic of the oscillation output f1 based on the differential signal. The oscillator includes a switching unit configured to alternately switch between a first state where a first connecting terminal and a second connecting terminal are connected to a storage unit for access of an external computer to the storage unit, and a second state where the first connecting terminal and the second connecting terminal are respectively connected to a first signal path and a second signal path via a frequency reduction unit such that the output signals from the frequency reduction unit are extracted to an external frequency measuring unit. | 01-29-2015 |