A resonance device is provided for reducing the influence on the resonant frequency of the resonance device of the electric charge borne by an insulating film of a frame. The resonance device includes a resonator including a vibration portion and a frame disposed in at least a part of a vicinity of the vibration portion. The frame includes a holding body and an insulating film, with the holding body holding the vibration portion to vibrate and the insulating film being formed above the holding body. A lower cover is provided having a recess forming at least a part of a space in which the vibration portion vibrates. An inner side surface of the insulating film is disposed at a first distance from an inner surface of a side wall defining the recess.

A passive wireless switch circuit and related apparatus are provided. In examples discussed herein, an apparatus includes a smaller number of voltage circuits configured to control a larger number of microelectromechanical systems (MEMS) switches. The voltage circuits passively generate a number of constant voltages based on a number of radio frequency (RF) signals to collectively identify each of the MEMS switches. A decoder circuit decodes the constant voltages to identify a selected MEMS switch and provides a selected constant voltage higher than a defined threshold voltage to close the selected MEMS switch. As such, it may be possible to eliminate active components and/or circuits from the passive wireless switch circuit, thus helping to reduce leakage and power consumption. It may be further possible to reduce conductive traces between the voltage circuits and the MEMS switches, thus helping to reduce routing complexity and footprint of the apparatus.

A resonator system is provided in which a combined overtone resonator device is excited with a two-dimensional mode of mechanical vibration in a cross sectional plane of a piezoelectric plate in response to an alternating voltage applied through an interdigitated electrode. The cross sectional plane extends along the width direction and the thickness direction, and the two-dimensional mode of mechanical vibration is a two-dimensional combined overtone mode of second and third order asymmetrical Lamb-wave overtones.

A microelectromechanical resonator, including a support structure, a resonator element suspended to the support structure, the resonator element including a plurality of sub-elements, and an actuator for exciting the resonator element into a resonance mode. The sub-elements are dimensioned such that they are dividable in one direction into one or more fundamental elements having an aspect ratio different from 1 so that each of the fundamental elements supports a fundamental resonance mode, which together define a compound resonance mode of the sub-element. The sub-elements are further coupled to each other by connection elements and positioned with respect to each other such that the fundamental elements are in a rectangular array configuration, wherein each fundamental element occupies a single array position, and at least one array position of the array configuration is free from fundamental elements.

A passive wireless sensor includes a substrate having at least one Microelectromechanical system (MEMS) piezoelectric resonator thereon. The MEMS piezoelectric resonator includes a piezoelectric layer between a top metal or semiconductor layer (top electrode layer) and a bottom metal or semiconductor layer (bottom electrode layer). The top electrode layer is a patterned top electrode layer including at least a first electrode for sensing an electrical signal and a second electrode for providing a ground reference. An antenna is connected to the first and/or second electrode for wirelessly transmitting the electrical signal and for receiving a wireless interrogation signal.

The temperature-dependent resistance of a MEMS structure is compared with an effective resistance of a switched CMOS capacitive element to implement a high performance temperature sensor.

An apparatus includes a microelectromechanical system (MEMS) die having a first surface and an opposing second surface. The MEMS die includes a surface-mounted resonator on the first surface and includes a first inductor. The apparatus also includes first and second dies. The first die has a third surface and an opposing fourth surface. The first die is coupled to the MEMS die such that the third surface of the first die faces the first surface of the MEMS die. The first and second surfaces are spaced apart. The first die includes an oscillator circuit and a second inductor. The oscillator circuit is coupled to the second inductor. The second inductor is inductively coupled to the first inductor. The second die is electrically coupled to the first die.

There are disclosed various apparatuses and methods for tuning a resonance frequency. In some embodiments there is provided an apparatus (200) comprising at least one input electrode (202, 204) for receiving radio frequency signals; a graphene foil (210) for converting at least part of the radio frequency signals into mechanical energy; at least one dielectric support element (212) to support the graphene foil (210) and to space apart the at least one input electrode (202, 204) and the graphene foil (210). The graphene foil (210) has piezoelectric properties. In some embodiments there is provided a method comprising receiving radio frequency signals by at least one input electrode (202, 204) of an apparatus (200); providing a bias voltage to the apparatus (200) for tuning the resonance frequency of the apparatus (200); and converting at least part of the radio frequency signals into mechanical energy by a graphene foil (210) having piezoelectric properties.

A microelectromechanical resonator includes a support structure, a resonator element suspended to the support structure, and an actuator for exciting the resonator element to a resonance mode. The resonator element includes a plurality of adjacent sub-elements each having a length and a width and a length-to-width aspect ratio of higher than 1 and being adapted to a resonate in a length-extensional, torsional or flexural resonance mode. Further, each of the sub-elements is coupled to at least one other sub-element by one or more connection elements coupled to non-nodal points of the of said resonance modes of the sub-elements for exciting the resonator element into a collective resonance mode.

According to one embodiment, a sensor module includes at least one sensor and at least one switch. The sensor includes a first piezoelectric element. The first piezoelectric element includes a first electrode. The first piezoelectric element is set with a resonance frequency to resonate at a vibration frequency of a detection target. The switch includes a second piezoelectric element. The second piezoelectric element includes a second electrode connected to the first electrode and a third electrode electrically separated from the second electrode.