The present disclosure relates to circuitry for driving a piezoelectric transducer based on an input signal. The circuitry comprises: primary driver circuitry configured to receive the input signal and to output a primary driving signal to the piezoelectric transducer based on the input signal; and secondary driver circuitry configured to receive an error signal indicative of an error between the input signal and the primary driving signal and to output a secondary driving signal to the piezoelectric transducer based on the error signal, wherein the primary driver circuitry and the secondary driver circuitry both comprise switching converter circuitry.

A resonance method for a vibration system for resonant vibration of an excitation unit having a vibrating mass includes detecting a deflection of the vibrating mass, differentiating the deflection to form a velocity of the vibrating mass; generating from the deflection and the velocity a mechanical phase position; forming from the mechanical phase position a corrected phase position by using a correction value; forming, based on the corrected phase position, an electrical angular frequency with a P-regulation; integrating the electrical angular frequency to determine an electrical phase position; forming from the electrical phase position a correction factor by using a trigonometric function; and applying the correction factor to an excitation setpoint value to generate a corrected excitation setpoint value. Also disclosed are a converter, an excitation unit having the converter, and a vibration system having the excitation unit and the vibrating mass.

An ultrasonic apparatus includes an ultrasonic transducer, a transmitting circuit, a receiving circuit, a Q-factor measuring circuit, and a frequency measuring circuit. The ultrasonic transducer is a three-terminal ultrasonic transducer that includes a transmitting electrode, a receiving electrode, and a common electrode. The transmitting circuit outputs a driving signal to the transmitting electrode to cause the ultrasonic transducer to transmit ultrasonic waves. The receiving circuit receives a receive signal from the receiving electrode. The frequency measuring circuit measures a resonant frequency of the ultrasonic transducer from a reverberation signal in the receive signal. The Q-factor measuring circuit measures a Q factor of the ultrasonic transducer from the reverberation signal in the receive signal.

Methods and apparatuses provide a phacoemulsification probe, wherein the probe has a piezoelectric actuator coupled with a needle configured to be inserted into an eye of a patient; and a processor configured to sequentially drive the actuator electrically in a range of frequencies, to measure a respective electrical power input to the actuator at each of the frequencies in the range, to identify a frequency in the range of frequencies wherein a metric of the electrical power input is a maximum, and to estimate from the identified frequency a mechanical resonant frequency of the actuator, and to drive the actuator electrically at the mechanical resonant frequency.

A hookah device (202) which attaches to a hookah (246). The hookah device (202) comprises a plurality of ultrasonic mist generator devices (201) for generating a mist for inhalation by a user. The hookah device (202) comprises a driver device (202) which controls the mist generator devices (201) to maximize the efficiency of mist generation by the mist generator devices (201) and optimize mist output from the hookah device (202).

A hookah device (202) which attaches to a hookah (246). The hookah device (202) comprises a plurality of ultrasonic mist generator devices (201) for generating a mist for inhalation by a user. The hookah device (202) comprises a driver device (202) which controls the mist generator devices (201) to maximize the efficiency of mist generation by the mist generator devices (201) and optimize mist output from the hookah device (202).

A hookah device (202) which attaches to a hookah (246). The hookah device (202) comprises a plurality of ultrasonic mist generator devices (201) for generating a mist for inhalation by a user. The hookah device (202) comprises a driver device (202) which controls the mist generator devices (201) to maximize the efficiency of mist generation by the mist generator devices (201) and optimize mist output from the hookah device (202).

An acoustophoretic system is controlled and driven to attain a desired level of performance. An RF controller and a driver provide a frequency and power to an acoustic transducer, which can be implemented as a piezoelectric element, which presents a reactive load or a complex load. A controller implements a control technique for efficient transducer operation. The control technique can locate a frequency for operation that is at a reactance minimum or maximum for the system to produce a modal pattern and to provide efficient operation of the transducer. A method of detecting a minimum or maximum reactance in a acoustophoretic system used to trap, separate, deflect, cluster, fractionate or otherwise process particles or secondary fluids or tertiary fluids in a primary fluid and utilizing the frequency of the detected reactance to operate the acoustophoretic system.

An ultrasound-based handheld animal and plant tissue ablation instrument includes a housing internally provided with a control board and a drive board, and an ultrasonic vibrator fixedly connected to a front end of the housing. The ultrasonic vibrator includes an ultrasonic transducer and an amplitude transformer. The amplitude transformer is fixedly connected to a front end of the ultrasonic transducer, changes an amplitude of vibration input by the ultrasonic transducer and transmits out the vibration. The control board is provided with a power supply, a DCDC conversion unit, a main control unit, a DCDC power adjustment unit and a sampling unit. The drive board is provided with a drive unit, a transformer unit and a resonance unit. The housing includes a first section and a second section. The end of the first section away from the second section is the front end of the housing.

A system may include a signal generator configured to generate a raw waveform signal and a modeling subsystem configured to implement a discrete time model of an electromagnetic load that emulates a virtual electromagnetic load and further configured to modify the raw waveform signal to generate a waveform signal for driving the electromagnetic load by modifying the virtual electromagnetic load to have a desired characteristic, applying the discrete time model to the raw waveform signal to generate the waveform signal for driving the electromagnetic load, and applying the waveform signal to the electromagnetic load.