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.

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.

An oscillator control system includes an non-linear oscillator structure configured to oscillate about an axis; a driver circuit configured to generate a driving signal to drive the oscillator structure; a detection circuit configured to measure an angle amplitude and a phase error of the oscillator structure; an amplitude controller configured to generate a reference oscillator period based on the measured angle amplitude; a period and phase controller configured to receive the reference oscillator period and the measured phase error from the detection circuit, generate at least one control parameter of the driving signal based on the reference oscillator period and the measured phase error, and determine a driving period of the driving signal based on the reference oscillator period and the measured phase error. The driver circuit is configured to generate the driving signal based on the at least one control parameter and the driving period.

An oscillator control system includes an non-linear oscillator structure configured to oscillate about an axis; a driver circuit configured to generate a driving signal to drive the oscillator structure; a detection circuit configured to measure an angle amplitude and a phase error of the oscillator structure; an amplitude controller configured to generate a reference oscillator period based on the measured angle amplitude; a period and phase controller configured to receive the reference oscillator period and the measured phase error from the detection circuit, generate at least one control parameter of the driving signal based on the reference oscillator period and the measured phase error, and determine a driving period of the driving signal based on the reference oscillator period and the measured phase error. The driver circuit is configured to generate the driving signal based on the at least one control parameter and the driving period.

An example pulse generation circuit includes a parallel-to-serial circuit configured to convert parallel data to serial data according to parallel clock signal and a serial clock signal, the serial data comprises a sequence of pulses; a clock generator configured to generate a clock signal; and a phase controller configured to generate the serial clock signal from the clock signal based on a phase control signal.

An example pulse generation circuit includes a parallel-to-serial circuit configured to convert parallel data to serial data according to parallel clock signal and a serial clock signal, the serial data comprises a sequence of pulses; a clock generator configured to generate a clock signal; and a phase controller configured to generate the serial clock signal from the clock signal based on a phase control signal.

A phase frequency detector (PFD) includes a first circuit portion and a second circuit portion. The first circuit portion receives a reference signal and activates a first error signal if the phase of the reference frequency leads the phase of a feedback signal. The second circuit portion receives the reference and activates a second error signal if the phase of the reference frequency lags the phase of the feedback signal. The first circuit portion is powered by a first power supply, and the second circuit portion is powered by a second power supply. A PLL implemented using the PFD generates a frequency output with minimized jitter.

An example a phase-locked loop (PLL) circuit includes a sampling phase detector configured to receive a reference clock and a feedback clock and configured to supply a first control current and a pulse signal. The PLL further includes a charge pump configured to generate a second control current based on the first control current and the pulse signal. The PLL further includes a loop filter configured to filter the second control current and generate an oscillator control voltage. The PLL further includes a voltage controlled oscillator (VCO) configured to generate an output clock based on the oscillator control voltage. The PLL further includes a frequency divider configured to generate the reference clock from the output clock.

In a first clock frequency multiplier, multiple injection-locked oscillators (ILOs) having spectrally-staggered lock ranges are operated in parallel to effect a collective input frequency range substantially wider than that of a solitary ILO. After each input frequency change, the ILO output clocks may be evaluated according to one or more qualifying criteria to select one of the ILOs as the final clock source. In a second clock frequency multiplier, a flexible-injection-rate injection-locked oscillator locks to super-harmonic, sub-harmonic or at-frequency injection pulses, seamlessly transitioning between the different injection pulse rates to enable a broad input frequency range. The frequency multiplication factor effected by the first and/or second clock frequency multipliers in response to an input clock is determined on the fly and then compared with a programmed (desired) multiplication factor to select between different frequency-divided instances of the frequency-multiplied clock.

In a first clock frequency multiplier, multiple injection-locked oscillators (ILOs) having spectrally-staggered lock ranges are operated in parallel to effect a collective input frequency range substantially wider than that of a solitary ILO. After each input frequency change, the ILO output clocks may be evaluated according to one or more qualifying criteria to select one of the ILOs as the final clock source. In a second clock frequency multiplier, a flexible-injection-rate injection-locked oscillator locks to super-harmonic, sub-harmonic or at-frequency injection pulses, seamlessly transitioning between the different injection pulse rates to enable a broad input frequency range. The frequency multiplication factor effected by the first and/or second clock frequency multipliers in response to an input clock is determined on the fly and then compared with a programmed (desired) multiplication factor to select between different frequency-divided instances of the frequency-multiplied clock.