A mist inhaler device (200) for generating a mist for inhalation by a user. The device includes a mist generator device (201) and a driver device (202). The driver device (202) is configured to drive the mist generator device (201) at an optimum frequency to maximise the efficiency of mist generation by the mist generator device (201).

A high voltage driving circuit for driving a load receives a low voltage input signal and generates a high voltage output signal. A short circuit protection circuit including a first electronic switch operated by the low voltage input signal and a second electronic switch operated by a low voltage signal obtained by a voltage division of the output high voltage signal. The first electronic switch causing a first pull-up current to be sent to a capacitive element whose voltage controls an input of a threshold comparator. A second electronic switch causes a second pull-down current to be drawn from the capacitive element whose voltage controls the input of the threshold comparator. A short circuit detection signal is generated at an output of said threshold comparator, indicating a short circuit and capable of inhibiting operation of the driving circuit.

An amplifier system may include a first feedback loop coupled between an output of an amplifier to an input of a modulator for regulating an output voltage driven at the output of the amplifier to a first terminal of a load of the amplifier system, a sense resistor for sensing a physical quantity associated with the amplifier, a second control loop coupled to the sense resistor such that the sense resistor is outside of the second control loop, the second control loop configured to regulate a common-mode voltage at a second terminal of the load, and a common-mode feedforward circuit coupled to the sense resistor and configured to minimize effects of a signal-dependent common-mode feedback of the sense resistor.

Phacoemulsification apparatus includes a phacoemulsification handpiece having a needle and an electrical circuitry for ultrasonic vibrating the needle. A power source provides pulsed electrical power to the handpiece electrical circuitry and an input is provided for enabling a surgeon to select an amplitude of dislighted pulses and a pulse width. A control system and pulse duty cycle is provided for controlling the off duty cycle to insure heat dissipation before a subsequent pulse is activated, including a foot pedal switch.

A control console for a powered surgical tool. The console includes a transformer that supplies the drive signal to the surgical tool. A linear amplifier with active resistors selectively ties the ends of the transformer primary winding between ground and the open circuit state. Feedback voltages from the transformer windings regulate the resistances of the active resistors.

A vibration presentation device includes: an electrostatic or piezoelectric actuator; a first elastic body laminated on the actuator; a second elastic body laminated on the actuator on the opposite side to the first elastic body; an electrostatic or piezoelectric sensor disposed around the actuator; a cover that holds the first elastic body and the second elastic body such that the first elastic body and the second elastic body are compressed more than the actuator, the cover transmitting, when a pressing force in the laminate direction is applied to the cover from the outside, the pressing force to a sensor, and vibrating by vibration generated by the actuator; and a control device that drives the actuator when the sensor detects the pressing force.

A switched resonant power amplifier system for ultrasonic transducers is disclosed. The system includes an amplifier that receives and processes a driver output signal for generating a drive signal that is provided to an ultrasonic device for controlling output of the ultrasonic device. An output control circuit receives and processes a signal related to a feedback signal generated by the ultrasonic device and a divider reference signal, and generates a compensated clock signal that is adjusted for at least one of phase and frequency differences between the received feedback signal and the divider reference signal. A compensated drive circuit receives and processes the compensated clock signal for generating the divider reference signal, and for generating the driver output signal.

The present disclosure relates to driver circuitry for driving a piezoelectric transducer. The circuitry comprises: output stage circuitry configured to receive an input signal and to drive the piezoelectric transducer to produce the output signal; variable voltage power supply circuitry configured to output a supply voltage for the charge drive output stage circuitry, wherein the supply voltage output by the variable voltage power supply circuitry varies based on the input signal; a supply capacitor for receiving the supply voltage output by the variable voltage power supply circuitry; a reservoir capacitor; and circuitry for transferring charge between the reservoir capacitor and the supply capacitor.

A vibration damping system for a charged particle beam apparatus according to the present invention includes a column through which a charged particle beam passes, a vibration detection unit that detects vibration of the column, a damping mechanism that applies vibration to the column to suppress the vibration of the column, and a control device that controls the damping mechanism. The control device includes a damping gain control unit that amplifies a detection signal of the vibration detection unit with a set amplification factor and outputs an amplified detection signal as a control signal to the damping mechanism, and a saturation suppression unit that adjusts a feedback gain value of the damping gain control unit according to a detection signal of the vibration detection unit, a signal of the damping mechanism, and a maximum output value and a minimum output value of the damping mechanism.

Piezoelectric user interface arrangement comprises a voltage converter for controllably generating voltage waveforms driving one or more piezoelectric elements. The voltage converter has a control input. A controller is coupled to said control input to control an output voltage of said voltage converter. The controller has one or more scaling inputs. The controller forms said control signals to make said output voltage follow a target waveform as a function of time. The controller is configured to scale said target waveform on the basis of scaling information received through said one or more scaling inputs.