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.

Microphones including a housing defining a cavity, a plurality of conductors positioned within the cavity, at least one dielectric bar positioned within the cavity, and a transducer diaphragm. The conductors are structured to move in response to pressure changes while the housing remains fixed. A first conductor generates first electrical signals responsive to the pressure changes resulting from changes in an atmospheric pressure. A second conductor generates second electrical signals responsive to the pressure changes resulting from acoustic activity. The dielectric bar is fixed with respect to the cavity and remains fixed under the pressure changes. The dielectric bar is adjacent to at least one of the conductors. In response to an applied pressure that is an atmospheric pressure and/or an acoustic pressure, the transducer diaphragm exerts a force on the housing and displaces at least a portion of conductors with respect to the dielectric bar.

A microelectromechanical systems (MEMS) switching circuit and related apparatus is provided. In examples discussed herein, the MEMS switching circuit is configured to toggle (open or close) a number of MEMS switches without causing hot switching in any of the MEMS switches. More specifically, the MEMS switching circuit determines a switching sequence for toggling the MEMS switches such that each MEMS switch is only opened or closed under a very low current (e.g., <0.1 mA) or a very low voltage (e.g., <0.1 V). By operating the MEMS switches based on the determined switching sequence, it may be possible to protect the MEMS switches from hot switching damage, thus making it possible to employ the MEMS switches in an apparatus (e.g., a wireless communication device) to replace conventional switches for improved power amplifier efficiency and radio frequency (RF) performance.

A moisture detector includes a sensor chip and a moisture determining unit. The sensor chip includes a humidity detector having a detection surface on which to measure humidity, and also includes a heater heating the detection surface, and the moisture determining unit is configured to, after causing the heater to start heating, determine whether moisture is present on the detection surface based on a difference in changes in the humidity measured by the humidity detector.

An integrated sensor device including a first die, housing a sensor element to detect a quantity external to the sensor device and transduce the external quantity into an electrical sensing signal; a second die mechanically coupled to the first die so that the first and second dies are stacked on one another along one and the same axis; and at least one heater of a resistive type integrated in the first die and/or in the second die, having a first conduction terminal and a second conduction terminal configured to couple respective first and second conduction terminals of a signal generator for causing an electric current to flow, in use, between the first and second conduction terminals of the heater and generate heat by the Joule effect. It is possible to carry out calibration in temperature of the sensor element.

An MEMS microphone is provided, comprising: a first substrate; a vibration diaphragm supported above the first substrate by a spacing portion, the first substrate, the spacing portion, and the vibration diaphragm enclosing a vacuum chamber, and a static deflection distance of the vibration diaphragm under an atmospheric pressure being less than a distance between the vibration diaphragm and the first substrate; and a floating gate field effect transistor outputting a varying electrical signal, the floating gate field effect transistor including a source electrode and a drain electrode both provided on the first substrate and a floating gate provided on the vibration diaphragm.

In accordance with an embodiment, a MEMS sensor includes a MEMS arrangement having a movable electrode and a stator electrode arranged opposite the movable electrode. The MEMS sensor includes a first bias voltage source, which is connected to the stator electrode and which is configured to apply a first bias voltage to the stator electrode. The MEMS sensor further includes a common-mode read-out circuit connected to the stator electrode by a capacitive coupling and comprising a second bias voltage source, which is configured to apply a second bias voltage to a side of the capacitive coupling that faces away from the stator electrode.

A MEMS component includes a MEMS sound transducer having a membrane structure and an assigned counterelectrode structure, and a circuit unit, which is electrically coupled to the MEMS sound transducer and which in a first operating mode of the MEMS sound transducer in the audio frequency range detects an audio output signal of the MEMS sound transducer on the basis of a deflection of the membrane structure relative to the counterelectrode structure, the deflection being brought about by an acoustic sound pressure change, and in a second operating mode of the MEMS sound transducer in the ultrasonic frequency range to drive and read the MEMS sound transducer as an ultrasonic transceiver.

A circuit device includes a drive circuit driving a resonator, an oscillation circuit having the resonator and a variable capacitance circuit coupled to an oscillation loop including the drive circuit, and a D/A converter circuit that performs D/A conversion on frequency control data and outputs a first voltage signal and a second voltage signal which are differential signals. The variable capacitance circuit includes a first variable capacitance capacitor, to one end of which the first voltage signal is input and, to the other end of which a first bias voltage is input and a second variable capacitance capacitor, to one end of which the second voltage signal is input and, to the other end of which a second bias voltage is input.

A method is provided for checking a sensor value of a MEMS sensor. In the process, an output signal of the MEMS sensor is detected and the sensor value is ascertained as a function of the output signal. In addition, frequency components of the output signal are examined and a determination is made as to whether the ascertained sensor value is reliable or unreliable as a function of the examination of the frequency components. If the sensor value is determined to be unreliable, the sensor value is discarded or provided with a lower weighting, or a warning it output relating to the unreliability of the sensor value or an item of information about the unreliability of the sensor value is stored.