Abstract: Techniques are provided for segmented windings of a coupled inductor within a DC-DC voltage converter or regulator. In an example, a coupled inductor circuit can include a first winding comprising a conductive coil having a central axis, and a second winding configured to magnetically couple with the first winding. The second winding can have a plurality of individual segments. Each individual segment can form a fraction of one turn of the second winding. Each segment can include a first conductor, a ground conductor, and a first switch to selectively couple, and selectively isolate, the first conductor and the ground conductor.

Abstract: To provide a power converter which can maintain the stability and the response of the feedback control system, even if the frequency characteristic of the chopper circuit changes according to change of driving condition. A power converter is provided with a chopper circuit which has reactor and switching device; and a control circuit which changes a feedback value of duty ratio of the switching device so that a deviation between a target value of output voltage and a detection value of output voltage approaches to 0, wherein the control circuit changes a frequency characteristic of the feedback control, based on at least any two or more of information on the output voltage, information on an input voltage, and information on duty ratio.

Abstract: A novel method to operate a switching regulator is presented. The method includes the generation of at least two reference signals. A first reference signal is a constant DC voltage signal and a second reference signal is a periodic ramp sawtooth signal at a given frequency. It also includes the generation of a feedback signal by using the output voltage of the switching regulator. In one method, a capacitor is either charged by a bias current or discharged by a switch. A first comparator is configured to compare a first constant DC reference voltage signal to a feedback signal. A second comparator is configured to compare a periodic ramp sawtooth signal to a voltage signal on the capacitor. In an alternative method, a comparator is configured to compare the feedback signal to either the periodic ramp sawtooth reference signal or the constant DC reference signal depending on the switching operation of the switching regulator. The periodic ramp sawtooth reference signal can be either positive or negative.

Abstract: A piezoelectric device includes: a first electrode provided above a substrate; a piezoelectric layer provided above the first electrode; and a second electrode provided above the piezoelectric layer. The piezoelectric layer includes a plurality of layers that includes a composite oxide of a Perovskite structure containing potassium, sodium, and niobium. The piezoelectric layer has a first region and a second region in a 3 ?m×3 ?m region of a plane perpendicular to a thickness direction of the piezoelectric layer. The first region is a region in which the ratio of an atomic concentration (atm %) of potassium with respect to the sum of the atomic concentration (atm %) of potassium and an atomic concentration (atm %) of sodium is 0.30 to 0.45, and the second region is a region in which the ratio is 0.55 to 0.75.

Abstract: A transformer including a piezoelectric plate and interdigital electrodes is provided. The interdigitated electrodes includes a plurality of conductive strips disposed over the piezoelectric plate. A cross-sectional Lamé mode resonance is excited in a cross sectional plane of the piezoelectric plate in response to input voltage applied through the interdigitated electrode, producing a voltage gain. A device including the aforementioned transformer is also provided.

Abstract: An apparatus includes an input voltage, a comparator configured to generate a pulsed-width modulation signal based upon variation in the input voltage using a reference signal, and a switched mode power supply control circuit configured to control a power supply in voltage mode based at least upon the first pulsed-width modulation signal.

Abstract: The semiconductor device includes a semiconductor element substrate having an insulation property, and a wire for positioning the semiconductor element with respect to the semiconductor element substrate. The semiconductor element substrate includes a disposition region for disposing the semiconductor element. The wire is provided at least at a part of the periphery of the disposition region.

Abstract: An input device includes a substrate structure, a conductive adhesive layer, and a piezoelectric structure. The conductive adhesive layer is disposed over the substrate structure. The conductive adhesive layer includes an adhesive portion and a plurality of metal particles, and the plurality of metal particles are substantially aligned in a first direction. The piezoelectric structure is disposed over the conductive adhesive layer. The piezoelectric structure extends in a second direction that is perpendicular to the first direction.

Abstract: A piezoelectric actuator (1) includes: a piezoelectric element (3); and a first frictional portion (10) and a second frictional portion (12) that are disposed on one principal surface (2d) of the piezoelectric element (3). The first frictional portion (10) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from one of the end surfaces (2a) is less than ? L, where L represents a length in the longitudinal direction of the piezoelectric element (3). The second frictional portion (12) is disposed at a position other than the antinodes of the piezoelectric element (3) at which a distance from the other of the end surfaces (2b) is less than ? L.

Abstract: There is provided a laminated substrate with a piezoelectric thin film, comprising: a substrate; an electrode film formed on the substrate; and a piezoelectric thin film formed on the electrode film, wherein the piezoelectric thin film is made of an alkali niobium oxide represented by a composition formula of (K1?xNax) NbO3 (0<x<1), having a perovskite structure, and oriented preferentially in (001) plane direction, and contains a metallic element selected from a group consisting of Mn and Cu at a concentration of 0.2 at % or more and 0.6 at % or less.

Abstract: A piezoelectric drive device includes: a vibrating body having a first surface and a second surface provided with a recessed portion; and a piezoelectric element provided on the first surface. The recessed portion and the piezoelectric element have an overlap region when viewed in a normal direction of the second surface.

Abstract: A rectifier includes a first stage to convert an AC signal to a first rectified signal and a second stage to convert the AC signal to a second rectified signal. Each stage includes a MOSFET, a differential amplifier with a predetermined gain, and an analog buffer coupled to the output of the differential amplifier. The differential amplifier generates an amplified signal based on a difference between an input signal voltage and an output signal voltage. The analog buffer outputs a gate signal to switch the MOSFET based on the amplified signal. Switching of the MOSFET converts the AC signal corresponding to the input signal voltage to a corresponding one of the first rectified signal and the second rectified signal. The first and second rectified signals may be combined to form a DC signal for driving a load.

Abstract: A switching power supply device includes a voltage conversion transformer, a primary-side control semiconductor device, a rectification and smoothing circuit, an output voltage detection circuit, a failure detection circuit, and a switch. The primary-side control semiconductor device generates a driving signal which controls a switching element connected to a primary winding of the transformer. The rectification and smoothing circuit is connected to a secondary winding of the transformer. The output voltage detection circuit detects a secondary-side output voltage of the transformer and transmits a feedback signal corresponding to the output voltage to the primary-side control semiconductor device through an insulated signal transmitter. The failure detection circuit detects a failure on a secondary side of the transformer. The switch cuts off a current flowing to the insulated signal transmitter if the failure detection circuit detects a failure.

Abstract: An acoustic wave device includes: a first substrate made of a piezoelectric material; an acoustic wave element located on the first substrate; a bump located on the first substrate; a second substrate located on the first substrate through the bump, the second substrate facing the first substrate across an air gap; and a support layer that is located in at least a part of a periphery of the first substrate, is in contact with a side surface of the first substrate, and has a less linear thermal expansion coefficient than the first substrate.

Abstract: A microelectromechanical system includes a piezoelectric drive and a control unit coupled to the piezoelectric drive and designed to control the piezoelectric drive based on a change of the admittance and/or the impedance of the piezoelectric drive.

Abstract: The motor has a stator unit covered with a resin. The stator unit has a stator core, a coil, a circuit board, and an insulator. The insulator has a cylindrical portion and a circumferential-direction positioning portion. Below the stator core, the cylindrical portion surrounds a central axis. The circumferential-direction positioning portion protrudes outwards in a radial direction from an outer circumferential surface of the cylindrical portion. At least a part of the circuit board and the circumferential-direction positioning portion are opposed to each other in a circumferential direction. In addition, a lower end of the circumferential-direction positioning portion is positioned above a lower end of the cylindrical portion.

Abstract: Described embodiments provide a Micro-Electro-Mechanical System (MEMS) vibration energy harvester. The energy harvester includes a buckled multi-layer beam that includes a plurality of stacked layers. The plurality of stacked layers includes at least one piezoelectric layer. Each one of the plurality of stacked layers has a determined stress level and a determined thickness. The determined stress level includes at least a compressive stress. The plurality of stacked layers achieves a desired total stress level of the beam to achieve substantial deformation of the beam in at least one direction when a proof mass is added to the beam. In response to applied external vibrations having a vibration frequency and an acceleration amplitude, the beam deflects and deforms to provide strain to the at least one piezoelectric layer, thereby generating an electrical charge to provide a continuous power output in response to the external vibrations.

Abstract: A voltage reducing circuit comprises a power switch circuit portion comprising a high-side and low-side field-effect-transistors connected at a switch node. The power switch circuit portion has an on-state wherein the high-side transistor is enabled and the low-side transistor is disabled and, vice versa, an off-state. An energy storage circuit portion comprising an inductor connected to the switch node is arranged to provide an output voltage. A drive circuit portion receives a pulse width modulation control signal and outputs pulse width modulated (PWM) drive signals. A pre-biasing circuit portion applies bias voltages to the gate terminals of the high-side and low-side transistors in response to the PWM drive signals, wherein the pre-biasing circuit portion is arranged such that the bias voltage applied to the gate terminal of the currently disabled transistor is set to an intermediate voltage before switching between the on-state and off-state.

Abstract: A buck-boost charge pump includes a flying capacitor and a switch network. The switch network couples an input terminal to a first terminal of the flying capacitor using a first double switch and the second terminal of the flying capacitor to a power supply voltage terminal using a second switch in a charging phase of a boost mode, the input terminal to the second terminal of the flying capacitor using a third switch and the first terminal of the flying capacitor to an output terminal using the fourth switch in both a discharging phase of the boost mode and a charging phase of a buck mode, and the power supply voltage terminal to the first terminal of the flying capacitor using a first switch and the second terminal of the flying capacitor to the output terminal using a second double switch in a discharging phase of the buck mode.

Abstract: Direct-current-to-direct-current (DC-DC) power converters that include two or more multi-quadrant, multi-level, DC-DC, switching converter subcircuits, connected in parallel at respective input and output sides, so as to provide a multi-channel, multi-quadrant, multi-level configuration, are disclosed. The DC-DC power converters further include a control circuit configured to control the switching converter subcircuits so that corresponding switching semiconductors in each of the switching converter subcircuits are switched in an interleaved manner. In some embodiments, each of the switching converter subcircuits is a three-level, neutral-point-clamped, four-quadrant DC-DC converter circuit. In other embodiments, each of the switching converter subcircuits is a three-level, neutral-point-clamped, two-quadrant DC-DC converter circuit. In any of these embodiments, a filter capacitor may be connected between across a pair of output terminals at the output sides of the switching converter subcircuits.