Abstract: Two oscillators produce respective signals at two different frequencies each dependent upon a parameter such as temperature in accordance with a polynomial with coefficients which are different for the two oscillators. A ratio of the frequencies is inverse to a ratio of a selected one of the coefficients of the polynomials. A mixer produces, at a sum or difference frequency of the two signals, an output signal for which a corresponding coefficient of a respective polynomial is substantially zero. The arrangement can be cascaded to produce zero coefficients for a plurality of terms in the polynomial.

Abstract: A downhole crystal-based clock that is substantially insensitive to the factors that cause frequency deviation. The clock may be maintained at a predetermined temperature using a temperature sensing device and a heating device, where the predetermined temperature corresponds to the temperature at which the crystal experiences only slight frequency deviation as a function of temperature. A microprocessor may monitor the clock and compensate for long-term aging effects of the crystal according to a predetermined algorithm. The predetermined algorithm may represent long-term aging effects of the crystal which were derived by comparing the crystal clock to a more accurate clock (e.g., an atomic clock) prior to placing the clock downhole. In this manner, the crystal-based clock may be substantially free from the factors that cause frequency, and therefore time variations.

Abstract: A circuit relates to phase and frequency-locked loop circuits (PLL and FLL circuits) with a controllable tracking oscillator whose signal phase relationship or frequency, respectively, is influenced by an external parameter, a reference oscillator, as well as a phase or frequency comparator, the output signal of which is used to control the tracking oscillator in such a way that any phase or frequency errors are reduced. A circuit provides for an element for the measurement of the external parameter (such as a microprocessor) which is capable of receiving a signal representing the output signal of the phase or frequency comparator, and convert it into a measurement value that represents the present value of the external parameter. This external parameter can, for example, represent the ambient temperature or the supply voltage of the tracking oscillator.

Abstract: A crystal oscillator having tunable ferroelectric components. A first ferroelectric capacitor is coupled to an automatic frequency control line for fine tuning the reference frequency. A second ferroelectric capacitor is coupled to temperature compensation control circuitry that applies a correction voltage to the second capacitor to vary the reference frequency in response to ambient temperature changes. A third ferroelectric capacitor has a capacitance that is adjusted and fixed during manufacture to set the initial tolerance of the crystal oscillator at ambient temperature.

Abstract: A ring oscillator having a stable output signal without influence of MOS devices is disclosed. The ring-oscillator has a bias circuit to drive a plurality of delay cells. The bias circuit has a first loading unit with a p-n junction, a second loading unit with a p-n junction, and a resistor electrically connected to the p-n junction of the second loading unit. The second loading unit and the resistor are positioned at a current path of a current mirror, and the first loading unit is positioned at another current path of the current mirror. The area of the p-n junction in the second loading unit is not equal to the area of the p-n junction in the first loading unit. The magnitudes of the current passing on the two current paths are only controlled by characteristics of the p-n junctions of the first and second loading units.

Abstract: An apparatus and method are provided for operating a processor core. This may include a first circuit to operate at a frequency that is dependent on a power supply voltage. A frequency control circuit may be provided to control a frequency of the first circuit by directing a voltage regulator to increase or decrease the power supply voltage.

Abstract: An apparatus that uses a linear voltage regulator to reject power supply noise in a temperature sensor is provided. Further, a method for using a linear voltage regulator to reject power supply noise in a temperature sensor is provided. Further, a method and apparatus that uses a differential amplifier with a source-follower output stage as a linear voltage regulator for a temperature sensor is provided.

Abstract: A liquid crystal driver IC comprising: a power circuit; an electric volume for varying an output voltage from the power circuit; a temperature detector; and a correction table for storing an electric volume control value corresponding to a temperature detected by the temperature detector. The power circuit includes: a first power circuit having a first temperature-voltage characteristic; a second power circuit having a second temperature-voltage characteristic; and a temperature gradient selection circuit for outputting a voltage conforming with a desired temperature gradient characteristic based on output voltages from the first and second power circuits. The temperature detector detects an actual temperature based on the first and second temperature-voltage characteristics.

Abstract: Method for acquiring frequency of a desired channel having a carrier frequency FMAIN, for a dynamic receiver frequency FMOBILE, from a starting frequency FSTART, in the presence of high power adjacent interfering channels, wherein the starting frequency FSTART is shifted from FMAIN by not more than a predetermined frequency gap &Dgr;F, the method includes the steps of determining a first frequency boundary and a second frequency boundary, detecting channels within a filtering bandwidth, selecting a dominant channel from the detected channels, progressing the dynamic receiver frequency FMOBILE towards the carrier frequency of the dominant channel, detecting when the step of progressing has exceeded one of the first frequency boundary and the second frequency boundary, restarting the step of detecting channels, from the other of the one of the first frequency boundary and the second frequency boundary, and repeating from the step of detecting channels.

Abstract: A crystal-less oscillator circuit with trimmable current control. In one embodiment, the present invention provides an oscillator circuit comprising a digital to analog converter circuit for generating a current, a band gap reference circuit for generating a voltage, and a relaxation oscillator circuit for creating a frequency based on the current and the voltage. In one embodiment, the digital to analog converter circuit comprises a trimmable current control. In one embodiment, the relaxation oscillator circuit is coupled to a frequency doubler circuit wherein the frequency is passed through the frequency doubler circuit for generating a second frequency. In another embodiment, the present invention provides a phase locked loop circuit comprising a phase detector circuit and the aforementioned oscillator circuit. In another embodiment, the present invention provides a microcontroller comprising a phase locked loop circuit comprising a phase detector circuit and the aforementioned oscillator circuit.

Abstract: A sheet substrate for use in manufacturing surface-mount crystal oscillators has a plurality of container bodies fabricated thereon. Each of the container bodies is capable of accommodating at least one IC chip, and has a bottom face formed with a plurality of mount terminals and a top face which is capable of forming a crystal unit thereto. On the sheet substrate, each of the container bodies has a conductive path extending from the container body to an adjacent container body and connected to a mount terminal of the adjacent container body, and a chip carrying terminal connected to one end of the conductive path for use in electric connection with the IC chip.

Abstract: With first, second and third current exchanger circuits cascaded, a current in proportion to a difference between an ambient temperature Ta and a reference temperature Tr is input to the first current exchanger circuit. The first current exchanger circuit supplies a current in proportion to the square of Ta−Tr to the second current exchanger circuit, the second current exchanger circuit supplies a current in proportion to the fourth power of Ta−Tr to the third current exchanger circuit, and the third current exchanger circuit outputs a current in proportion to the fifth power of Ta−Tr. Each of the first, second and third current exchanger circuits has a configuration which does not require a high supply voltage enough to drive a series circuit of three or more diodes.

Abstract: A piezoelectric oscillator includes a piezoelectric element, and an oscillation circuit connected to one of two terminals of the piezoelectric element. One terminal of first capacitance element of which the other terminal is grounded is connected to at least one of the two terminals of the piezoelectric element. A series circuit including a resistor, which has adjustable resistance, can be adjusted and a second capacitance element is connected in parallel to the first capacitance element.

Abstract: A temperature compensated oscillator keeping the area of a capacitor array and the bit number of a memory from increasing and allowing for high precision is provided. A adjusting method of such a resonator and an integrated circuit for temperature compensated oscillation are also provided. A capacitor array and a variable capacitance diode are connected and used as a load capacitance in an oscillation circuit, and the capacitance value of the former is digital-controlled and that of the latter is analog-controlled, so that the amount of compensation data necessary for the digital control is reduced and highly precise temperature compensation is permitted.

Abstract: A highly stable single chip resonator controlled oscillator with automatic amplitude control and biasing is designed for manufacture with monolithic integrated circuit technologies. Analog and digital output buffers with elaborate control for power saving purposes and sophisticated start-up and power-up circuits ensure, that a crystal controlled oscillation is safely induced at start-up and that the amplitude of oscillation is continuously controlled during operation to reach low phase noise and reduce power consumption of the circuit.

Abstract: An oven controlled crystal oscillator has an onboard processor containing an algorithm used to generate a frequency compensating signal based on a predetermined relationship and a monitored current consumption of a heater.

Abstract: A reference clock oscillating circuit intermittently carries out an oscillating operation on the basis of an oscillation control signal from an oscillation control circuit. A frequency multiplying circuit successively measures the period of a reference clock signal by using a measuring clock signal generated therein during a period for which the reference clock signal is input from the reference clock oscillating circuit, and generates a multiplied clock signal by using the period data thus measured. During a period for which no reference clock signal is input, the multiplied clock signal is generated by using the period data stored in a period data register. The interval of the intermittent oscillating operation is set on the basis of temperature variation of IC or the like.

Abstract: A pseudo-cubic function generator circuit comprises a CMOS inverter which is applied with a detected voltage of a sensor and supplied with a power supply voltage, and a voltage divider circuit for dividing the power supply voltage, wherein an output terminal of the CMOS inverter is connected to a voltage division point of the voltage divider circuit to generate an output voltage from the voltage division point. The pseudo-cubic function generator circuit can directly generate a large voltage change in a simple circuit configuration with a reduced noise component, and facilitates a setting of each parameter for specifying a cubic function curve. The parameter is set, for example, by scaling substantial gate areas of a P-MOS FET and an N-MOS FET which constitutes the CMOS inverter.

Abstract: A temperature-compensated crystal oscillator (TCXO) comprises a voltage-controlled crystal oscillator (VCXO) having a crystal unit, a compensating voltage generator for generating a compensating voltage applied to the voltage-controlled crystal oscillator, a low pass filter inserted between the compensating voltage generator and voltage-controlled crystal oscillator, and a switching element connected in parallel with the low pass filter for short-circuiting across the low pass filter. In a manufacturing process of the temperature-compensated crystal oscillator, switching element is brought into a conducting state when an excitation electrode of the crystal unit is irradiated with an ion beam for adjusting the oscillation frequency.

Abstract: The present invention relates to a method for compensating temperature in a crystal oscillator including a capacitor array consisted of a first bank of unit capacitors each with low capacitance and a second bank of unit capacitors each with high capacitance.

Abstract: Clock generation circuits for an integrated circuit device are provided including a temperature sensor circuit, the temperatures sensor circuit including a calibration circuit responsive to a temperature coding signal and a temperature sensor. The temperature sensor circuit has a first or test mode state in which a temperature output signal of the temperature sensor circuit is based on a temperature sensor output control signal and a second or normal operating mode state in which the temperature output signal is based on the temperature sensor and the calibration circuit. A clock period controller circuit includes a calibration circuit responsive to a period coding signal. The clock period controller circuit generates a period control signal based on the temperature output signal and the calibration circuit of the clock period controller circuit. A clock generator circuit generates a clock signal based on the period control signal.

Abstract: A method for synchronizing a local reference frequency in a mobile station includes measuring a current ambient condition of the mobile station and using stored data indicating variance of the local reference frequency with known ambient conditions to determine the method by which the local reference frequency is synchronized.

Abstract: A circuit including an oscillator circuit, a current generator circuit and a voltage generator circuit. The oscillator circuit may be configured to generate an output signal having a frequency in response to (i) a first control signal and (ii) a second control signal. The current generator may be configured to generate said first control signal in response to a first adjustment signal. The voltage generator circuit may be configured to generate the second control signal in response to a second adjustment signal.

Abstract: A temperature compensated crystal includes a crystal package including a package board and a crystal oscillating piece, conductive patterns for constituting a temperature compensating circuit formed on a surface of the package board, exterior terminals formed at corners of the board, temperature compensating components formed on the surface of the board, and resin molded part enveloping the surface of the board. With a lower surface of a crystal package serving as a component mounting area, it is not necessary to provide an additional printed circuit board required for mounting of temperature compensating components, and it is possible to provide a compact TCXO having a surface area corresponding to that of a crystal package.

Abstract: An analog memory cell that may be incorporated into a low power oscillator is provided. The analog memory cell stores an analog voltage as a digital signal and converts the digital signal back to an analog voltage to allow continued generation of an accurate constant output voltage regardless of temperature-dependent leakage currents associated with parasitic diodes and non-ideal devices. The accurate constant output voltage provided by the analog memory cell may be used by the low power oscillator to generate an accurate low frequency output signal. This accurate low frequency output signal may be used to maintain long-term timing accuracy in host devices during sleep modes of operation. Incorporation of the analog memory cell in the low power oscillator is fully implementable in a CMOS process.

Abstract: A method for operating a wide band voltage controlled oscillator comprises using a control voltage to tune the capacitance of at least one hybrid n+ and p+ gate-doped voltage variable capacitor of the wide band voltage controlled oscillator. A hybrid voltage variable capacitor includes a substrate, a well adjacent to the substrate, a first and second set of contact elements adjacent to the well, a first channel layer adjacent to the well and bound by the first set of contact elements, a first insulating layer adjacent to the first channel layer, a first electrode adjacent to the first insulating layer, a second channel layer adjacent to the well and bound by the second set of contact elements, a second insulating layer adjacent to the second channel layer, and a second electrode adjacent to the second insulating layer.

Abstract: Method for acquiring frequency of a desired channel having a carrier frequency FMAIN, for a dynamic receiver frequency FMOBILE, from a starting frequency FSTART, in the presence of high power adjacent interfering channels, wherein the starting frequency FSTART is shifted from FMAIN by not more than a predetermined frequency gap &Dgr;F, the method includes the steps of determining a first frequency boundary and a second frequency boundary, detecting channels within a filtering bandwidth, selecting a dominant channel from the detected channels, progressing the dynamic receiver frequency FMOBILE towards the carrier frequency of the dominant channel, detecting when the step of progressing has exceeded one of the first frequency boundary and the second frequency boundary, restarting the step of detecting channels, from the other of the one of the first frequency boundary and the second frequency boundary, and repeating from the step of detecting channels.

Abstract: A temperature-compensated crystal oscillator with good phase noise characteristics has a crystal unit, a voltage-variable capacitive element inserted in a closed oscillating loop including the crystal unit, and an amplifier for keeping oscillation in the closed oscillating loop. The frequency vs. temperature characteristics of the temperature-compensated crystal oscillator can be compensated for by the temperature compensating voltage input thereto. The temperature compensating voltage is applied to an anode of the voltage-variable capacitive element, and a voltage to prevent a current from flowing through the voltage-variable capacitive element is applied to a cathode of the voltage-variable capacitive element. The voltage-variable capacitive element preferably comprises a variable-capacitance diode.

Abstract: Disclosed is an amplifier apparatus that corrects mismatching of the filter transmission characteristic due to a change in the temperature of the amplifier apparatus itself and thereby stably amplifies the high-frequency signal. The amplifier apparatus converts a signal to be processed into one having an intermediate frequency band to thereby execute amplification processing.

Abstract: The present invention is for a thermally controlled package for oscillators, particularly evacuated miniature surface acoustical wave oscillators (EMSO) devices. In a preferred embodiment the surface acoustical wave device is bonded directly to a heated substrate. The package is evacuated to improve temperature characteristics. A temperature heater, sensor, and control controller are utilized to maintain the internal package temperature above ambient. In one embodiment there is an additional substrate layer that house components that are not sensitive to temperature with interconnects electrically connecting the heated substrate and the additional substrates.

Abstract: A temperature compensated clock and method of clocking systems are provided. The clock preferably has an oscillator for generating an oscillating waveform signal at a preselected frequency and a frequency divider responsive to the oscillator for dividing the frequency of the oscillating waveform signal. A temperature monitoring circuit is positioned responsive to a voltage input signal independent of temperature and a voltage input signal proportional to temperature for monitoring temperature variations. A temperature compensating circuit, preferably including a programmable scaling circuit, is responsive to the frequency divider and the temperature monitoring circuit for scaling the divided frequency of the generated waveform and thereby advantageously produces a temperature compensated output timing signal.

Abstract: The temperature of an oscillation circuit (47) is detected by a temperature detection circuit (13), a cubic term voltage generation circuit of a control voltage generation circuit (23) generates a cubic term voltage as a control voltage based on an output voltage of the temperature detection circuit (13), and a frequency adjustment circuit (45) changes an oscillation frequency of the oscillation circuit (47) by the control voltage.

Abstract: An oscillator includes first, second and third inverters (1, 2, 3) connected in series. A feedback path is connected from the output terminal of the third inverter (3) to the input terminal of the first inverter 1 through a resistor (5) while a second feedback path is connected from the output terminal of the second inverter (2) to the input terminal of the first inverter (1) through a capacitor (4). The second feedback path further includes a resistor (6) having a temperature coefficient larger than that of resistor (5) is inserted to adjust the charge/discharge trigger voltage and charge/discharge time of the capacitor (4).

Abstract: A frequency tracking circuit and method comprising a master crystal oscillator circuit is used for frequency tracking between a handset and a base station comprising a calibration subsystem for taking a temperature measurement, a reference control circuit for determining a numerical value needed to align a handset frequency with a base station frequency, an adder for adding the numerical value to a previous numerical value determined by the reference control circuit, a latch for latching the output of the adder, and a low precision master crystal oscillator for clocking the frequency of the latch. The most significant bit from the latch is input into a phase/frequency detector for forcing a voltage controlled oscillator to track a desired frequency.

Abstract: The device (1) includes a mixer (4) which generates a signal (S4) having a frequency (F4) equal to the difference between two frequencies (F2, F3), which are those of two signals (S2, S3) each generated by a generator (2, 3) and which vary parabolically as a function of the temperature (T) with quadratic coefficients (&bgr;1,&bgr;2) that are different to each other. In order for the frequency (F4) of the signal (S4) generated by the mixer (4) to be at least substantially independent of the temperature (T), the generators (2, 3) are arranged such that the ratio of the quadratic coefficients (&bgr;1,&bgr;2) is equal to the inverse of the ratio of values (F2r, F3r) that the corresponding frequencies (F2, F3) have at a determined temperature (Tr).

Abstract: A low noise block down converter accommodates two local oscillators within one shielding chamber in a metal shielding box and has a conductive bar provided between two dielectric resonators included in the local oscillators respectively. The conductive bar prevents electromagnetic coupling between the two dielectric resonators. Therefore, the device dimension can be made small compared to the conventional case in which two local oscillators are completely separated from each other by a metal wall.

Abstract: A crystal oscillator according to the present invention prevents abnormal oscillation at a temperature in a low-temperature area equal to or lower than an ordinary temperature. The crystal oscillator is configured such that a crystal vibrator is made to abut against a heat source, and the temperature of the crystal vibrator can be kept higher than a temperature where abnormal oscillation occurs. The temperature of the crystal vibrator is assumed to be, for example, higher than 0° C. Additionally, as the heat source, for example, a power transistor that amplifies an oscillation output is used.

Abstract: A system and method for programming a digitally tunable oscillator is provided. A desired output frequency is received. A tuning effect of a set of digital tuning words on a crystal resonant frequency is determined, and valid parameters of an algorithm for translating and tuning the crystal resonant frequency to a value within an error tolerance of the desired frequency, based on the determined tuning effect are calculated. Valid parameters are preferably calculated based on an intermediate tuning value, sorted by ascending divide parameter of the algorithm, and then evaluated in sorted order for ability of a tuning effect to null frequency error to within the error tolerance. The valid set of calculated parameters are then programmed into a nonvolatile memory. The oscillator control parameters may remain unprogrammed until all necessary parameters are defined.

Abstract: An oscillation circuit uses a SAW oscillator and is able to control the oscillation frequency easily and correct the temperature characteristic of the oscillator so that an oscillation signal with high temperature stability can be generated. A clock signal CLK having a prescribed frequency difference from the ideal oscillation frequency is generated by the SAW oscillator 10. Register 30 is driven by a frequency-divided clock signal obtained by dividing the frequency of the clock signal at a predetermined frequency division rate. In-phase signal SI and quadrature signal SQ generated corresponding to the data Da that is incremented by a prescribed addition value F every period of the frequency-divided clock signal are output, and the clock signal is IQ-modulated on the basis of these signals. The frequency error of clock signal CLK can be corrected, and an output signal Sout having near ideal oscillation frequency can be obtained.

Abstract: A feedback circuit and amplifiers using a vibrator comprising a piezoelectric body having a bismuth layered compound as the main ingredient thereof are provided so as to generate oscillation. Load capacitors comprising the feedback circuit together with the vibrator are formed. These load capacitors each have, as the main ingredient thereof, a dielectric body which decreases in the relative dielectric constant with the increase in temperature in the region not less than one half the temperature range from −20 to 80° C., and in which the &egr;-TC is not less than 5000 ppm/° C., wherein the &egr;-TC is an average change rate of the relative dielectric constant in the above-described temperature range and is represented by (Cmax−Cmin)/(C20·100), where Cmax is the maximum value of capacitance in the above-described temperature range, Cmin is the minimum value of capacitance in the above-described temperature range, and C20 is the capacitance at 20° C.

Abstract: An adjustable oscillating frequency function generator. The oscillating frequency of the function generator can be adjusted externally. The oscillation frequency is independent of the magnitude of the voltage source. Therefore, a pulse signal that withstands the voltage source signal can be provided.

Abstract: A temperature compensated crystal oscillator has a crystal oscillating unit and at least one part for temperature compensation and oscillation circuits. The temperature compensated crystal oscillator has a layered structure and a planar thin film resistor. The layered structure has an upper layer on which the crystal oscillator and the part are mounted, and at least one layer on which conduction patterns are formed. The planar thin film resistor is arranged on an upper surface of a bottom layer of the layered structure so as to adjust an output frequency of the temperature compensated crystal oscillator. Therefore, an area occupied by the resistor for adjusting the output frequency can be minimized by inserting the resistor between the layers.

Abstract: A frequency tracking circuit and method comprising a master crystal oscillator circuit is used for frequency tracking between a handset and a base station comprising a calibration subsystem for taking a temperature measurement, a reference control circuit for determining a numerical value needed to align a handset frequency with a base station frequency, an adder for adding the numerical value to a previous numerical value determined by the reference control circuit, a latch for latching the output of the adder, and a low precision master crystal oscillator for clocking the frequency of the latch. The most significant bit from the latch is input into a phase/frequency detector for forcing a voltage controlled oscillator to track a desired frequency.

Abstract: A frequency controlled oscillator (100) is manufactured using an array (200) of mechanically interconnected oscillator bases (110) having component cavities (130) and wiring patterns therein. A frequency control component (120) serves as a cover for a cavity within the array, and in addition is electrically connected to oscillator components (140, 150) mounted within the cavity to regulate the frequency of electrical oscillation. Both the oscillator bases and finished oscillators may be tested while still in the array, prior to being separated from each other. In a most preferred embodiment, the array of oscillator bases are manufactured from a polymeric sheet material laminated with electrically conductive traces. The polymeric sheet material is selectively punched or formed prior to lamination so that intermediate and upper layers (112, 113) have predetermined sections removed.

Abstract: A method and apparatus are provided for generating a control signal for compensating a temperature controlled crystal oscillator system for changes in an ambient temperature. The method includes the steps of providing a set of second-order coefficients relating ambient temperature to frequency drift over at least a portion of an operating temperature range of the temperature controlled crystal oscillator system and calculating a control signal for compensating the temperature controlled crystal oscillator system for the frequency drift due to the ambient temperature based upon the set of second-order coefficients.

Abstract: An apparatus and method are provided for operating a processor core. This may include a first circuit to operate at a frequency that is dependent on a power supply voltage. A frequency control circuit may be provided to control a frequency of the first circuit by directing a voltage regulator to increase or decrease the power supply voltage.

Abstract: A temperature compensated crystal oscillator has first and second layered structures, an IC chip, a crystal vibrating chip, a resin mold portion and a metal cover. Each of the first and second layered structures has a cavity formed therein. The cavity formed in the second layered structure does not overlap with the cavity of the first layered structure. The IC chip is inserted into the cavity of the first layered structure. The crystal vibrating chip is inserted into the cavity of the second layered structure. The resin mold portion is formed by charging resin into the cavity of the first layered structure. The metal cover is arranged on the upper surface of the second layered structure for covering an opening of the cavity of the second layered structure.

Abstract: A method and system of compensating for reference frequency drift utilizes time stamps from a networked reference clock to adjust a local crystal oscillator of a communications device. In an example embodiment, a microprocessor arrangement of the communications device obtains a synchronization time stamp from a networked clock arrangement and synchronizes the local oscillator clock and a clock circuit of the microprocessor with the time stamp. After a predetermined time duration has transpired, a calibration time stamp is obtained from the network clock and the difference between the calibration time stamp and the current time of the clock circuit is extracted. The clock circuit and the networked clock arrangement are then synchronized and the local crystal oscillator is adjusted for crystal aging as a function of the difference between the calibration time stamp and the current time of the clock circuit.

Abstract: Based on an initial crystal coefficient value, a processor generates a control signal for a frequency synthesizer. The processor estimates a new crystal coefficient value based on a comparison of the frequency of the output of the frequency synthesizer against a target output frequency in relation to a crystal temperature value.

Abstract: A temperature compensation technique is disclosed which allows to obtain a compensated clock signal. The temperature compensation technique comprises the use of a thermal model of the oscillator with a temperature sensor in order to accurately compute the oscillator frequency, irrespective of time-variations and rates.