One aspect of the present invention relates to a driver of a vibrator including: a control section; and an alternating current signal generation section configured to generate an alternating current signal based on an output from the control section, and to apply the alternating current signal to the vibrator, wherein the control section is configured to lower a frequency of the alternating current signal, and to change, after the frequency change, at least one of a voltage ratio and a phase difference of the alternating current signal such that the ellipse ratio of the elliptical motion changes from a first ellipse ratio to a second ellipse ratio, the second ellipse ratio has a larger ratio of a component in a moving direction in the elliptical motion to a component in a direction perpendicular to the moving direction in the elliptical motion than the first ellipse ratio.

A membrane switch in which a first conductive part is formed on a first substrate, a second conductive part is formed on a second substrate, and the substrates are layered via a spacer such that the conductive parts face each other with a space therebetween, and an organic material showing piezoelectricity is filled, or disposed in the space such that an air gap is present, are useful for obtaining an output signal corresponding to an applied pressure.

An ink-jet head driving circuit includes: PMOS transistors each of which has an Nwell area, a drain terminal and a source terminal, the PMOS transistors connected to a piezoelectric element for jetting ink from a nozzle; and an NMOS transistor connected to the drain terminals of the PMOS transistors. The source terminals and Nwell areas of the PMOS transistors are connected respectively to power sources, and voltage of one of the power sources connected to the Nwell area of each of the PMOS transistors is equal to or higher than the highest voltage of the power sources connected to the source terminals of the PMOS transistors.

The disclosure relates to a circuit arrangement that includes a first DC-DC converter that is connected on the output side to a capacitor. A first terminal of the capacitor is a supply voltage terminal and a second terminal of the capacitor is a reference potential terminal. The circuit arrangement also includes a second DC-DC converter, which is connected on the input side with the capacitor and on the output side to a first terminal of a piezo actuator. The second terminal of the piezo actuator is connected to the first terminal of the capacitor.

A control apparatus controls driving of an oil feeding unit. The oil feeding unit includes a piezoelectric body that deforms in response to a voltage applied thereto, and a reservoir to store lubricating oil. The capacity of the reservoir changes in accordance with deformation of the piezoelectric body so as to discharge lubricating oil from the oil feeding unit. The control apparatus includes N driving circuits 71a to 71n configured to apply voltages to the piezoelectric body (where N is an integer equal to or greater than two). The N driving circuits 71a to 71n are connected in parallel to the piezoelectric body. During oil feeding, the control apparatus uses a predetermined number of the driving circuits selected from the N driving circuits. The predetermined number is smaller than

A bulk acoustic wave (BAW) resonator comprises: a seed layer disposed over a substrate; a first electrode disposed over the seed layer; and a second electrode disposed over a piezoelectric layer. The seed layer has a thickness in the range of approximately 30 Å to approximately 150 Å.

An electronic device includes an integrated circuit, a flexible heat spreader, an actuator, and a controller. The actuator is coupled to the flexible heat spreader and the controller is configured to control the actuator between a first actuation mode and a second actuation mode. When in the first actuation mode, the actuator positions the flexible heat spreader with an air gap between the flexible heat spreader and the integrated circuit such that the flexible heat spreader is thermally separated from the integrated circuit to increase a thermal impedance between the flexible heat spreader and the integrated circuit. When in the second actuation mode, the actuator positions the flexible heat spreader in thermal contact with the integrated circuit without the air gap there between to reduce the thermal impedance between the flexible heat spreader and the integrated circuit.

There is provided a displacement sensor which can precisely detect the amount of displacement given by an operator. A touch sensor which is a type of the displacement sensor has a piezoelectric element, a voltage converting unit and a detecting unit. The piezoelectric element instantaneously generates a voltage proportional to a pressing force (the amount of pressing). The voltage converting unit converts the voltage generated by the piezoelectric element, into a voltage proportional to a transition determined based on a predetermined time constant determined by an impedance of a resistor of the voltage converting unit and capacitances of a capacitor and the piezoelectric element, and a pressing force. The detecting unit integrates output voltages of the voltage converting unit, and calculates the pressing force (the amount of pressing) based on an integration value.

The inventive concept discloses a piezoelectric energy harvesting array and a method of manufacturing the same. The manufacturing method may include forming a plurality of piezoelectric energy harvesting devices; connecting masses to one side of the piezoelectric energy harvesting devices and connecting the other side of the piezoelectric energy harvesting devices facing the masses to a base; and individually tuning a resonant frequency of each of the piezoelectric energy harvesting devices to prevent mismatch of resonant frequency when the masses vibrate.

A nebulizing driving apparatus is used to drive a piezoelectric material of a nebulizing module. The nebulizing driving apparatus includes a driving circuit, a control circuit and a feedback circuit. The feedback circuit detects an electrical data fed back from the piezoelectric material and sends the electrical data to the control circuit when the control circuit is configured to control the driving circuit to drive the piezoelectric material with a driving frequency. According to the electrical data, the control circuit is configured to control the driving circuit to drive the piezoelectric material with a working frequency.