A method for multiphase frequency to voltage conversion includes generating for each cycle of an oscillating input, one of a plurality of non-overlapping clocks. A respective voltage in proportion to an input frequency of the oscillating input, is generated in response to each of the non-overlapping clocks, with a respective one of a plurality of frequency to voltage converters. Each of the respective voltages is summated to generate a voltage sum proportional to the input frequency.

In one aspect, a method of adjusting a first oscillating signal, includes generating a relationship prediction responsive to a deep learning model configured to predict a relationship between a fundamental quantity of a first oscillating signal and a fundamental quantity of a second oscillating signal, and applying an adjustment to the first oscillating signal responsive to the relationship prediction to produce an adjusted oscillating signal, wherein the adjusted oscillating signal replaces the second oscillating signal.

A reference frequency signal generator comprises a plurality of ovenized reference crystal oscillators (OCXOs) having different turn-over-temperatures, a selector logic circuit coupled to outputs of the OCXOs, a temperature sensor, and a controller coupled to an output of the temperature sensor. The selector logic circuit outputs one of the outputs of the OCXOs based on a control signal from the controller. The controller also generates control signals for the OCXOs. In some implementations, the reference frequency signal generator includes a phase-locked loop or a fractional output divider coupled to the output of the selector logic circuit and configured to receive a calibration signal from the controller.

There is provided a dual-output microelectromechanical system (MEMS) resonator. The MEMS resonator can be operated selectively and concurrently in an in-plane mode of vibration and an out-of-plane mode of vibration to obtain respectively a first electrical signal having a first frequency, and a second electrical signal having a second frequency being less than the first frequency. The first and second electrical signals are mixed to obtain a third electrical signal having a third frequency, where the third frequency is proportional to a temperature of the MEMS resonator. The temperature is determined based on the third frequency. Values of the first and second frequencies can be adjusted based on the determined temperature to compensate for frequency deviations due to temperature deviations. There is also provided methods and systems for determining the temperature of the dual-output MEMS, for compensating the frequency, and a method of manufacturing the dual-output MEMS.

There is provided a dual-output microelectromechanical system (MEMS) resonator. The MEMS resonator can be operated selectively and concurrently in an in-plane mode of vibration and an out-of-plane mode of vibration to obtain respectively a first electrical signal having a first frequency, and a second electrical signal having a second frequency being less than the first frequency. The first and second electrical signals are mixed to obtain a third electrical signal having a third frequency, where the third frequency is proportional to a temperature of the MEMS resonator. The temperature is determined based on the third frequency. Values of the first and second frequencies can be adjusted based on the determined temperature to compensate for frequency deviations due to temperature deviations. There is also provided methods and systems for determining the temperature of the dual-output MEMS, for compensating the frequency, and a method of manufacturing the dual-output MEMS.

Provided is an oscillator including: a first resonator; a second resonator; a first oscillation circuit generating a first oscillation signal by oscillating the first resonator; a second oscillation circuit generating a second oscillation signal that has frequency-temperature characteristics different from frequency-temperature characteristics of the first oscillation signal by oscillating the second resonator; a clock signal generation circuit generating a clock signal with a frequency that is temperature compensated by temperature compensation data; and a processing circuit performing time digital conversion processing based on the first oscillation signal and the second oscillation signal, and obtaining the temperature compensation data based on measurement data of the time digital conversion processing.

Systems and methods for digital synthesis of an output signal using a frequency generated from a resonator and computing amplitude values that take into account temperature variations and resonant frequency variations resulting from manufacturing variability are described. A direct frequency synthesizer architecture is leveraged on a high Q resonator, such as a film bulk acoustic resonator (FBAR), a spectral multiband resonator (SMR), and a contour mode resonator (CMR) and is used to generate pristine signals.

Provided is an oscillator including: a first resonator; a second resonator; a first oscillation circuit generating a first oscillation signal by oscillating the first resonator; a second oscillation circuit generating a second oscillation signal that has frequency-temperature characteristics different from frequency-temperature characteristics of the first oscillation signal by oscillating the second resonator; a clock signal generation circuit generating a clock signal with a frequency that is temperature compensated by temperature compensation data; a storage unit storing information on a learned model that is machine-learned to output data corresponding to the temperature compensation data with respect to input data; and a processing circuit obtaining the temperature compensation data by performing processing based on the information on the learned model with respect to the input data based on the first oscillation signal and the second oscillation signal.

A circuit apparatus includes an oscillation circuit that causes a resonator to oscillate to produce an oscillation signal, an oven control circuit that controls a heater provided in correspondence with the resonator, a non-volatile memory that stores control data, a holding circuit that holds the control data transferred from the non-volatile memory, and a processing circuit that carries out a process based on the control data held in the holding circuit. After a power source voltage is supplied, the processing circuit carries out the process of transferring the control data from the non-volatile memory to the holding circuit, and after the transfer of the control data is completed, the processing circuit causes based on a data transfer end signal the oven control circuit to start operating.

Systems, methods, and devices of the present disclosure relate, generally, to compensating for frequency error of a reference signal supplied to a clock-tracking-loop due to temperature. Error characteristics of a crystal oscillator that supplies the reference signal are used to compensate for possible frequency errors. Other systems, methods and devices are disclosed.