Abstract: Disclosed herein are IC structures, packages, and devices that include III-N transistors integrated on the same substrate or die as resonators of RF filters. An example IC structure includes a support structure (e.g., a substrate), a resonator, provided over a first portion of the support structure, and an III-N transistor, provided over a second portion of the support structure. The IC structure includes a piezoelectric material so that first and second electrodes of the resonator enclose a first portion of the piezoelectric material, while a second portion of the piezoelectric material is enclosed between the channel material of the III-N transistor and the support structure. In this manner, one or more resonators of an RF filter may be monolithically integrated with one or more III-N transistors. Such integration may reduce costs and improve performance by reducing RF losses incurred when power is routed off chip.

Abstract: A circuit and method for starting-up a crystal oscillator is described. A crystal resonator is configured to be coupled to a start-up circuit including an H-bridge circuit having a number of switches. A plurality of switch control signals are generated in response to detecting a zero-crossing event of the motional current in the crystal resonator. The switches of the H-bridge circuit are controlled by the switch control signals to apply a voltage to the terminals of the crystal resonator in a first polarity during a first switch control phase and a second opposite polarity during a second switch control phase. During a respective first subphase of the respective switch control phase, the plurality of switches are configured in a first configuration to couple the supply node to a respective crystal resonator terminal.

Abstract: A vibrator device includes a base; and a vibrator element including a quartz crystal vibrator element attached to the base via a first metal bump, in which the first metal bump is disposed on a straight line inclined within a range of +55° to +65° or ?65° to ?55° with respect to an X axis of the quartz crystal constituting the quartz crystal vibrator element in plan view seen from a direction in which the base and the quartz crystal vibrator element are arranged.

Abstract: A clock generation circuit includes a switched capacitor circuit for providing a discrete amount of charge to a resonator for sustaining energization of the resonator at specific portions of the clock cycle.

Abstract: A sensor assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a substrate layer formed on a localized surface of a rotatable gas turbine engine component, and at least one pair of transducers deposited on the substrate layer.

Abstract: A resonance device that includes a lower cover formed from non-degenerate silicon; a resonator having a degenerate silicon substrate with a lower surface facing the lower cover, and including first and second electrode layers laminated on the substrate with a piezoelectric film formed therebetween and having a surface opposing an upper surface of the substrate. Moreover, the lower surface of the substrate has an adjustment region where a depth or height of projections and recesses formed on the surface is larger than that in another region of the lower surface of the substrate or is a region where an area of the projections and recesses is larger than that in the other region of the lower surface of the substrate.

Abstract: A fluid sensing device is provided, including a main body and a light sensing unit. The main body includes a casing and a rotary member. A containing chamber is formed in the casing. The rotary member is rotatably disposed in the casing, and the rotary member has at least one transparent portion. A fluid flows into the containing chamber to drive the rotary member rotating around a central axis. The light sensing unit includes a first light transceiver module and a second light transceiver module disposed near the main body in an asymmetrical manner with respect to the central axis to transmit and receive the light passing through the translucent portion.

Abstract: A self-powered wireless switch includes at least one micro generator and a control panel for transmitting wireless control signals, the micro generator including a magnet assembly and a coil assembly being moved relatively to one another to generate an induced current within the coil assembly; the coil assembly including an iron core and a wire winding around the outside of the iron core to form a magnetic coil; the magnet assembly including a permanent magnet and magnet conductive plates arranged at two sides of the opposite magnetic poles of the permanent magnet. The self-powered wireless switch enables the magnetic assembly and the coil assembly to move relatively to one another and converts the mechanical energy to electricity, thereby achieving self-power generation and providing electricity to the control panel for transmission of wireless control signals.

Abstract: A method for operating a resonant measurement system has at least one: adjustment device, electric actuation device, electromagnetic vibration generator, vibrating element, and vibration recorder. The adjustment device generates an output signal to trigger the electric actuation device, the electric actuation device provides an electric excitation signal to the electromagnetic drive, the electromagnetic drive excites the vibrating element to the same vibration in at least one normal mode, and the excited vibration is sensed by the vibration recorder and is output as an output signal. To approach, maintain and readjust a resonant point as an operating point of the resonant measurement system, the phase difference between the output signal of the vibration recorder and the adjustment device output signal is acquired, an adjustment deviation is calculated from a predefined phase difference and the acquired phase difference, and the adjustment deviation provided to the adjustment device as an input signal.

Abstract: Provided is a crystal vibration device in which it is difficult to transfer heat to a temperature-sensitive element and a crystal vibrator. A crystal vibration device 1 according to the present invention includes: a mounting board 2; connection electrodes 4a and 4b extending on a side surface of the mounting board 2 and reaching an upper surface 2a of the mounting board 2; a first package material 9 provided on the mounting board 2; a crystal vibrator 7 provided on an upper surface 9a of the first package material 9; and a temperature-sensitive element 14 mounted on a lower surface 9b of the first package material 9. Each of the connection electrodes 4a and 4b has a first portion 4A located on the upper surface 2a of the mounting board 2.

Abstract: A SAW device includes a SAW chip formed of a piezoelectric substrate and an IDT formed thereon, a base substrate that supports the SAW chip, and a fixing member that fixes the SAW chip to the base substrate. The SAW chip that forms a cantilever is supported by the base substrate via the fixing member in a position where the IDT does not overlap with the fixing member in a plan view of the SAW chip. The length W of the SAW chip in a y-axis direction and the length D of the fixing member in the y-axis direction satisfy 1<D/W?1.6. The fixing member bonds the lower surface and side surfaces of the fixed end of the SAW chip to the base substrate.

Abstract: The invention relates to a method for operating control equipment (1) of a resonance circuit (2), wherein the control equipment (1) comprises at least two circuit elements (8, 9) connected in series, in particular each comprising a recovery diode (13, 14) connected in parallel, between which a connection (6) of the resonance circuit (2) is connected. According to the invention, the circuit elements (8, 9) are actuated as a function of the voltage detected at the connection (6). The invention further relates to control equipment (1) of a resonance circuit (2).

Abstract: A second piezoelectric vibrator (30) is located in a hollow portion (21) of the first piezoelectric vibrator (20) when seen in a plan view. A support (40) is a frame-shaped member, and the inside surface thereof supports the edge of a vibration member (10). The fundamental resonance frequency of the first piezoelectric vibrator (20) is lower than the fundamental resonance frequency of the second piezoelectric vibrator (30). In addition, the second piezoelectric vibrator (30) overlaps a loop of vibration generated in the vibration member (10) when the first piezoelectric vibrator (20) is driven at the fundamental resonance frequency. Preferably, the center of the second piezoelectric vibrator (30) overlaps the center of a loop of vibration generated in the vibration member (10) by the first piezoelectric vibrator (20).

Abstract: There are disposed a sealing member, a pair of electrode pads to electrically couple a piezoelectric resonator, a plurality of connection pads to electrically couple an integrated circuit element and the piezoelectric resonator, and wiring patterns to establish electrical continuity between the pair of electrode pads and the plurality of connection pads, and the piezoelectric resonator and the integrated circuit element are disposed side by side in plan view. An output wiring pattern establishes electrical continuity between one of the connection pads and an alternating current output terminal of an oscillation circuit, and a power source wiring pattern establishs electrical continuity between one of the connection pads and a direct current power source terminal of the oscillation circuit. The electrode pads are disposed closer to the power source wiring pattern than the output wiring pattern.

Abstract: A variable phase amplifier circuit is disclosed and its method of use in tuning devices having resonators. The variable phase amplifier receives an input differential signal pair. The input differential signal pair can be generated by a resonator device. The variable phase amplifier generates a modified differential signal pair in response to receiving the input differential signal pair. The variable phase amplifier provides a means to vary the phase of the modified differential signal pair with respect to the input differential signal pair, in an accurate and stable manner. If the modified differential signal pair with a phase shift introduced in it is fed back to the resonator device, the resonator will change its frequency of oscillation, where the new frequency of oscillation is a function of the phase of the modified differential signal pair.

Abstract: Embodiments relate to MEMS resonator structures and methods that enable application of a maximum available on-chip voltage. In an embodiment, a MEMS resonator comprises a connection between a ground potential and the gap electrode of the resonator. Embodiments also relate to manufacturing systems and methods that are less complex and enable production of MEMS resonators of reduced dimensions.

Abstract: It is possible to reduce the size of a surface acoustic wave (SAW) resonator by enhancing a Q value. In a SAW resonator in which an IDT having electrode fingers for exciting SAW is disposed on a crystal substrate, the IDT includes a first region disposed at the center of the IDT and a second region and a third region disposed on both sides of the first region. A frequency is fixed in the first region and a portion in which a frequency gradually decreases as it approaches an edge of the IDT is disposed in the second region and the third region. When the frequency of the first region is Fa, the frequency at an edge of the second region is FbM, and the frequency at an edge of the third region is FcN, the variations in frequency are in the ranges of 0.9815<FbM/Fa<0.9953 and 0.9815<FcN/Fa<0.9953, respectively.

Abstract: An ultrasound system for the generation of low-frequency high-power ultrasound includes a resonator for transmitting the ultrasound to a medium. To safely handle the ultrasound system, the ultrasound system has a light source illuminating a workspace of the ultrasound system.

Abstract: A highly sensitive micro-piezoelectric tunable resonator element and device that uses a tapered transition region from the actuator and sensor elements to the resonator beam to permit maximum mechanical energy transfer to the beam. A dual-resonator beam embodiment with a shared tuning element is provided in an alternative embodiment.

Abstract: A multilayer ceramic component includes a stack containing ceramic layers and electrode layers interspersed among the ceramic layers. The electrode layers contain copper and define first and second internal electrodes. First and second external contacts are on different sides of the stack. The first and second external contacts contain copper and are substantially perpendicular to the ceramic layers and electrode layers. The first internal electrode is connected to the first external contact and the second internal electrode is connected to the second external contact. The first and second internal electrodes overlap each other at a plane intersecting the stack. In areas adjacent to boundaries between the first and second external contacts and the ceramic layers, the first and second external contacts are not oxidized and material making-up the ceramic layers is not diminished. A bonding strength of the external contacts to the stack exceeds 50 N.

Abstract: The present invention relates to an oscillator. The oscillator includes a resonator unit configured to resonate terahertz waves generated by an active layer using intersubband transitions of a carrier. The oscillator further includes a strain generating unit configured to generate strain of the active layer. Still furthermore, the oscillator includes a control unit configured to control the strain generating unit in accordance with the oscillation characteristic (the frequency or the output) of the terahertz waves resonated by the resonator unit.

Abstract: A SAW device includes a SAW chip formed of a piezoelectric substrate and an IDT formed thereon, a base substrate that supports the SAW chip, and a fixing member that fixes the SAW chip to the base substrate. The SAW chip that forms a cantilever is supported by the base substrate via the fixing member in a position where the IDT does not overlap with the fixing member in a plan view of the SAW chip. The length W of the SAW chip in a y-axis direction and the length D of the fixing member in the y-axis direction satisfy 1<D/W?1.6. The fixing member bonds the lower surface and side surfaces of the fixed end of the SAW chip to the base substrate.

Abstract: A piezoelectric device includes an integrated circuit (IC) chip and a piezoelectric resonator element, a part of the piezoelectric resonator element being disposed so as to overlap with a part of the IC chip when viewed in plan. The IC chip includes: an inner pad disposed on an active face and in an area where is overlapped with the piezoelectric resonator when viewed in plan; an insulating layer formed on the active face; a relocation pad disposed on the insulating layer and in an area other than a part where is overlapped with the piezoelectric resonator element, the relocation pad being coupled to an end part of a first wire; and a second wire electrically coupling the inner pad and the relocation pad, the second wire having a relocation wire and a connector that penetrates the insulating layer, the relocation wire being disposed between the insulating layer and the active face.

Abstract: A MEMS resonator system that reduces interference signals arising from undesired capacitive coupling between different system elements. The system, in one embodiment, includes a MEMS resonator, electrodes, and at least one resonator electrode shield. In certain embodiments, the resonator electrode shield ensures that the resonator electrodes interact with either one or more shunting nodes or the active elements of the MEMS resonator by preventing or reducing, among other things, capacitive coupling between the resonator electrodes and the support and auxiliary elements of the MEMS resonator structure. By reducing the deleterious effects of interfering signals using one or more resonator electrode shields, a simpler, lower interference, and more efficient system relative to prior art approaches is presented.

Abstract: A periodic signal generator is configured to generate high frequency signals characterized by relatively low temperature coefficients of frequency (TCF). A microelectromechanical resonator, such as concave bulk acoustic resonator (CBAR) supporting capacitive and piezoelectric transduction, may be geometrically engineered as a signal generator that produces two periodic signals having unequal resonant frequencies with unequal temperature coefficients. Circuitry is also provided for combining the two periodic signals using a mixer to thereby yield a high frequency low-TCF periodic difference signal at an output of the periodic signal generator.

Abstract: It is possible to reduce the size of a surface acoustic wave resonator by enhancing the Q value. In a surface acoustic wave resonator in which an IDT having electrode fingers for exciting surface acoustic waves is formed on a crystal substrate, a line occupying ratio is defined as a value obtained by dividing the width of one electrode finger by the distance between the center lines of the gaps between one electrode finger and the electrode fingers adjacent to both sides thereof, and the IDT includes a region formed by gradually changing the line occupying ratio from the center to both edges so that the frequency gradually becomes lower from the center to both edges than the frequency at the center of the IDT.

Abstract: A resonator element includes a base portion which includes one end portion and the other end portion opposing the one end portion in a plan view, and a pair of vibrating arms which extend along a first direction from the one end portion of the base portion. The base portion includes a reduced width portion in which a width is gradually decreased along a second direction intersecting the first direction toward a direction side which is separated from the base portion along the first direction, in at least one of the one end portion and the other end portion, and a fixing portion is provided between the one end portion and the other end portion of the base portion.

Abstract: A piezoelectric vibrating piece, a piezoelectric vibrator, an oscillator, an electronic apparatus and a radio timepiece capable of reducing the size while suppressing reduction of rigidity and having excellent vibration characteristics. The piezoelectric vibrating piece includes a pair of vibrating arm portions in parallel to each other, a base portion integrally fixing base end portions of the pair of vibrating arm portions in a length direction, groove portions on main surfaces of the pair of vibrating arm portions and extending along the length direction, where each of the groove portions includes a first groove portion near a tip portion end of the vibrating arm portions and a second groove portion near the base end portion side of the vibrating arm portions with respect to the first groove portion, and the second groove portion is offset in a ?X axis direction with respect to the first groove portion.

Abstract: A capacitively-driven Micro-Electro-Mechanical System (MEMS) resonator is provided, in which a piezoresistively differential measurement is used to enable the MEMS resonator to transfer a signal. The MEMS resonator uses a Complementary Metal-Oxide-Semiconductor (CMOS) manufacturing process to make its oscillator and piezoresistor to achieve electrical insulation, thereby lowering the level of feedthrough signal.

Abstract: A resonator element includes a substrate including a vibrating portion that performs thickness-shear vibration and an excitation electrode provided on top and bottom main surfaces of the vibrating portion. Assuming that the average plate thickness calculated from the plate thicknesses of a plurality of regions of the vibrating portion is H and the plate thickness difference, which is a difference between the maximum and minimum values of the plate thicknesses of the plurality of regions of the vibrating portion, is ?H, 0%<?H/H?0.085% is satisfied as a relationship between H and ?H.

Abstract: A method of actuating a system comprising a movable component and an actuator configured to move the movable component comprises providing a control signal representative of a desired motion of the movable component. The control signal is supplied to one or more resonators. Each of the one or more resonators has a mode of oscillation representative of at least one elastic mode of oscillation of the system. The control signal is modified by subtracting from the control signal a signal representative of a response of the one or more resonators to the control signal. The actuator is operated in accordance with the modified control signal. Thus, undesirable elastic oscillations of the system which might occur if the system were operated with the original control system can be reduced.

Abstract: MEMS oscillators, which include a silicon-type, in particular piezoresistive resonators, can be used to provide a fixed, stable output frequency. Silicon has a natural temperature dependence of Young's modulus, therefore, as ambient temperature changes and/or the piezoresistive resonator is powered, the resonator temperature changes, and the resonance frequency of the resonator drifts. In order to account for the temperature drift of the piezoresistive resonator, the piezoresistive resonator itself is used as a temperature sensor. The relative resistance change of the piezoresistive resonator depends only on the relative temperature change and material property of the resonator. Therefore, an accurate temperature can be sensed directly on the piezoresistive resonator. The temperature drift information is provided to a frequency adjuster, which corrects the output frequency of the circuit.

Abstract: An oscillation device (electro-acoustic transducer (100)) includes an oscillation element (110) that has a vibrating member (120) and a piezoelectric element (111) that is attached to one surface of the vibrating member (120). The oscillation device includes a sheet-shaped waterproof member (140) that is constituted by a waterproof material. The oscillation device includes a frame-shaped supporting member (130) that holds an outer peripheral portion of the vibrating member (120) and an outer peripheral portion of the waterproof member (140) so that the waterproof member (140) and the oscillation element (110) face each other. The oscillation device includes a connection member (150) that partially connects mutual opposed surfaces of the oscillation element (110) and the waterproof member (140).

Abstract: In an electro-acoustic transducer 100 which is an oscillator device, a flat piezoelectric film 120 that moves expansively and contractively through the application of an electric field is disposed on at least one surface of a flat elastic member 110 in which a plurality of holes 111 penetrate a principal surface thereof. Since the stiffness of the elastic member 110 is adjusted by the holes 111, the stiffness impedance with respect to the piezoelectric film 120 can be matched optimally. Thus, it is possible to suppress the amount of vibration displacement and to complement the conversion efficiency of the piezoelectric film 120.

Abstract: Each of piezoelectric vibrators 110 includes an elastic member 112 and a piezoelectric element 111. The piezoelectric element 111 is attached to the elastic member 112. A supporting member 120 has an opening. A plurality of the piezoelectric vibrators 110 are arranged in the opening along a first direction. It is preferable that the plurality of piezoelectric vibrators 110 have the same fundamental resonance frequency. In addition, it is preferable that an arrangement pitch of the piezoelectric vibrators 110 is equal to or less than half the wavelength of the fundamental resonance frequency.

Abstract: An electrical circuit for emulating a capacitance, comprises a physical capacitor which is charged by charge flow from the input of the electrical circuit. An amplifier amplifies the voltage at the input of the electrical circuit such that the physical capacitor is charged with a larger change in voltage than the change in voltage at the input. This implements an effective multiplication of capacitance. A reset system resets the physical capacitor without drawing charge from the input of the electrical circuit. This extends the voltages which can be provided to the input.

Abstract: A package and method for manufacturing the package using a rivet having a head portion and a core portion protruding from a rear surface of the head portion. The package includes a plurality of substrates bonded to each other and a cavity that houses an object in a sealed state. The core portion is disposed in a through hole in a base substrate and electrically connects the object with the outside. The core portion is inserted into the through hole and a glass frit is formed between the through hole and the core portion and seals the rivet in the through hole. A gas relief passage is formed leading from a base end of the core portion to a surface of the head portion.

Abstract: A surface mount piezoelectric oscillator includes a piezoelectric resonator with a container main body, a plurality of external terminals, a mounting board with an IC chip, a plurality of connecting terminals, and a solder ball. The solder ball bonds the plurality of external terminals and the plurality of connecting terminals by melting and hardening. The solder bonding portion has approximately a circular shape with approximately a same size as a size of the connecting terminal of the mounting board. The solder ball placed on the connecting terminal of the mounting board is melted, self-aligned, and hardened so as to form a solder fillet of nearly axial symmetry. The solder fillet bridges between the both electrodes and bonds the connecting terminal of the mounting board and the solder bonding portion of the external terminal of the piezoelectric resonator.

Abstract: Electromechanical systems resonator structures, devices, circuits, and systems are disclosed. In one aspect, an oscillator includes an active component and a passive component connected in a feedback configuration. The passive component includes one or more contour mode resonators (CMR). A CMR includes a piezoelectric layer disposed between a first conductive layer and a second conductive layer. The conductive layers include an input electrode and an output electrode. The passive component is configured to output a first resonant frequency and a second resonant frequency, which is an odd integer harmonic of the first resonant frequency. The active component is configured to output a signal including the first resonant frequency and the second resonant frequency. This output signal can be a substantially square wave signal, which can serve as a clock in various applications.

Abstract: A piezoresistive MEMS oscillator comprises a resonator body, first and second drive electrodes located adjacent the resonator body for providing an actuation signal; and at least a first sense electrode connected to a respective anchor point. The voltages at the electrodes are controlled and/or processed such that the feedthrough AC current from one drive electrode to the sense electrode is at least partially offset by the feedthrough AC current from the other drive electrode to the sense electrode.

Abstract: It is possible to reduce the size of a surface acoustic wave (SAW) resonator by enhancing a Q value. In a SAW resonator in which an IDT having electrode fingers for exciting SAW is disposed on a crystal substrate, the IDT includes a first region disposed at the center of the IDT and a second region and a third region disposed on both sides of the first region. A frequency is fixed in the first region and a portion in which a frequency gradually decreases as it approaches an edge of the IDT is disposed in the second region and the third region. When the frequency of the first region is Fa, the frequency at an edge of the second region is FbM, and the frequency at an edge of the third region is FcN, the variations in frequency are in the ranges of 0.9815<FbM/Fa<0.9953 and 0.9815<FcN/Fa<0.9953, respectively.

Abstract: A transverse acoustic wave resonator includes a base, a resonator component, a number of driving electrodes fixed to the base and a number of fixing portions connecting the base and the resonator component. The resonator component is suspended above a top surface of the base and is perpendicular to the base. The driving electrodes are coupling to side surfaces of the resonator component. The resonator component is formed in a shape of an essential regular polygon. The driving electrodes and the resonator component jointly form an electromechanical coupling system for converting capacitance into electrostatic force. Besides, a capacitive-type transverse extension acoustic wave silicon oscillator includes the transverse acoustic wave resonator and a method of fabricating the transverse acoustic wave resonator are also disclosed.

Abstract: The invention relates to a method for operating control equipment (1) of a resonance circuit (2), wherein the control equipment (1) comprises at least two circuit elements (8, 9) connected in series, in particular each comprising a recovery diode (13, 14) connected in parallel, between which a connection (6) of the resonance circuit (2) is connected. According to the invention, the circuit elements (8, 9) are actuated as a function of the voltage detected at the connection (6). The invention further relates to control equipment (1) of a resonance circuit (2).

Abstract: A method of adjustment on manufacturing of a monolithic oscillator including circuit elements and a BAW resonator, this method including the steps of: a) forming the circuit elements and the resonator and electrically connecting them; b) covering the resonator with a frequency adjustment layer; c) measuring the output frequency of the oscillator; d) modifying the thickness of the frequency adjustment layer to modify the output frequency of the oscillator.

Abstract: A second piezoelectric vibrator (30) is located in a hollow portion (21) of the first piezoelectric vibrator (20) when seen in a plan view. A support (40) is a frame-shaped member, and the inside surface thereof supports the edge of a vibration member (10). The fundamental resonance frequency of the first piezoelectric vibrator (20) is lower than the fundamental resonance frequency of the second piezoelectric vibrator (30). In addition, the second piezoelectric vibrator (30) overlaps a loop of vibration generated in the vibration member (10) when the first piezoelectric vibrator (20) is driven at the fundamental resonance frequency. Preferably, the center of the second piezoelectric vibrator (30) overlaps the center of a loop of vibration generated in the vibration member (10) by the first piezoelectric vibrator (20).

Abstract: A pressure detecting device includes: a resonator whose oscillation frequency varies depending on a pressure; a first oscillation circuit that oscillates the resonator and outputs a signal of a frequency corresponding to the pressure; an AT-cut quartz crystal resonator; a second oscillation circuit that oscillates the AT-cut quartz crystal resonator and outputs a reference clock signal; a measuring unit that measures the reference clock signal by the use of a reciprocal counting method; a temperature detecting unit that detects a temperature of the resonator; and a storage unit that stores coefficients of a first approximating polynomial for calculating a first correction value used to compensate for a frequency-temperature characteristic of the measuring unit, wherein the frequency-temperature characteristic of the value measured by the measuring unit includes a frequency-temperature characteristic of the AT-cut quartz crystal resonator and a frequency-temperature characteristic of the resonator.

Abstract: In a SAW oscillator, each of a first SAW element and a second SAW element includes interdigital electrodes and a reflector formed on a piezoelectric material. A first oscillating circuit part forms an oscillating loop including the first SAW element. A second oscillating circuit part forms an oscillating loop including the second SAW element. The first and second oscillating circuit parts have an identical admittance property. The first and second SAW elements are configured that an electrode pitch is identical and an admittance property indicating a relation between a frequency and an admittance value is different therebetween. Further, a first intersection point between the admittance property of the first SAW element and the admittance property of the first oscillating circuit part and a second intersection point between the admittance property of the second SAW element and the admittance property of the second oscillating circuit part are at different frequencies.

Abstract: A SAW device includes a SAW chip formed of a piezoelectric substrate and an IDT formed thereon, a base substrate that supports the SAW chip, and a fixing member that fixes the SAW chip to the base substrate. The SAW chip that forms a cantilever is supported by the base substrate via the fixing member in a position where the IDT does not overlap with the fixing member in a plan view of the SAW chip. The length W of the SAW chip in a y-axis direction and the length D of the fixing member in the y-axis direction satisfy 1<D/W1?1.6. The fixing member bonds the lower surface and side surfaces of the fixed end of the SAW chip to the base substrate.

Abstract: It is possible to reduce the size of a surface acoustic wave (SAW) resonator by enhancing a Q value. In a SAW resonator in which an IDT having electrode fingers for exciting SAW is disposed on a crystal substrate, the IDT includes a first region disposed at the center of the IDT and a second region and a third region disposed on both sides of the first region. A frequency is fixed in the first region and a portion in which a frequency gradually decreases as it approaches an edge of the IDT is disposed in the second region and the third region. When the frequency of the first region is Fa, the frequency at an edge of the second region is FbM, and the frequency at an edge of the third region is FcN, the variations in frequency are in the ranges of 0.9815<FbM/Fa<0.9953 and 0.9815<FcN/Fa<0.9953, respectively.

Abstract: Periodic signal generators include an oscillator circuit, which is configured to generate a first periodic signal at an output thereof, and a piezoelectric-based microelectromechanical resonator. The resonator is configured to generate a second periodic signal at a first electrode thereof, which is electrically coupled to the oscillator circuit. A variable impedance circuit is provided, which is electrically coupled to a second electrode of the piezoelectric-based microelectromechanical resonator. The variable impedance circuit is configured to passively modify a frequency of the second periodic signal by changing an induced electromechanical stiffness in at least a portion of the piezoelectric-based microelectromechanical resonator.