Techniques for improving acoustic resonators and resonator structures are disclosed, including filters, oscillators and systems that may include such devices. A bulk acoustic wave (BAW) resonator may comprise a substrate. The bulk acoustic wave (BAW) may further comprise a plurality of piezoelectric layers including first, second, third and fourth piezoelectric layers acoustically coupled with one another and arranged over the substrate. The first, second, third and fourth piezoelectric layers may have respective piezoelectric axis orientations. The first, second, third and fourth piezoelectric layers may have respective thicknesses. Electromechanical coupling of the bulk acoustic wave (BAW) resonator may, but need not be limited.

A transmitting device for wireless transmission of measured parameters comprising a microcontroller and pulse generating elements connected to the microcontroller, the microcontroller being configured to receive at least one detection signal representative of at least one measured parameter value and being also configured to control the pulse generating elements so that the pulse generating elements generate at least one pulse position modulation (PPM) signal comprising information corresponding to the at least one measured parameter value, the transmitting device further comprising or being connectable to an antenna for the wireless transmission of the PPM signal, the pulse generating elements comprising an oscillator and a power amplifier connected to the oscillator in order to amplify the pulses output from the oscillator and to output the PPM signal.

An oscillation module includes an SAW filter, and a high-pass filter formed in an integrated circuit, the high-pass filter has a coil part, a capacitance part, and a first interconnection adapted to connect the coil part and the capacitance part to each other, and the capacitance part includes a capacitance array.

An acoustic-wave device with active calibration mechanism is provided. The acoustic-wave device with active calibration mechanism includes at least one acoustic-wave duplexer, a voltage-controlled oscillator (VCO), a frequency discriminator and a control circuit. The acoustic-wave duplexer includes a TX filter and an RX filter. The voltage-controlled oscillator includes a calibration resonator and a tunable negative impedance circuit. The TX filter, the RX filter and the calibration resonator are disposed on the same piezoelectric substrate. The frequency discriminator generates a calibration signal according to a frequency deviation of the calibration resonator. The control circuit is connected to the acoustic-wave duplexer and the frequency discriminator. The control circuit adjusts an operating frequency of the TX filter or an operating frequency of the RX filter according to the calibration signal.

A SAW resonator which, using a quartz crystal substrate with Euler angles (−1.5°≦φ≦1.5°, 117°≦θ≦142°, and 41.9°≦|ψ|≦49.57°, includes an IDT that excites a stop band upper end mode SAW, and an inter-electrode finger groove provided between electrode fingers configuring the IDT. When a wavelength of the SAW is λ, a first depth of the inter-electrode finger groove is G, a line occupation rate of the IDT is η, and an electrode film thickness of the IDT is H, λ, G, η and H satisfy the relationship of 0<H≦0.005λ, 0.01λ≦G≦0.09λ, and 0.18≦η≦0.71.

An oscillator includes: a bulk-acoustic wave (BAW) resonator having a first BAW resonator terminal and a second BAW resonator terminal; and an active circuit coupled to the first and second BAW resonator terminals and having a series resonance topology with: a first transistor; a second transistor; a first resistor; a second resistor; a capacitive network coupled to first and second BAW resonator terminals and to respective current terminals of the first and second transistors; and an inductor having a first inductor terminal and a second inductor terminal, the first inductor terminal coupled to the capacitive network, and the second inductor terminal coupled to ground terminal.

A clock oscillator, a clock oscillator production method and use method, and a chip including the clock oscillator are provided. The clock oscillator includes a resonator, a shock-absorbing material layer, and a base, and at least a part of the shock-absorbing material layer is located between the resonator and the base. In the clock oscillator, the shock-absorbing material layer is added between the resonator and the base, and the shock-absorbing material layer can effectively prevent a mechanical wave from being conducted between the base and the resonator, so that the resonator is protected from external vibration. This can ensure, when there is external vibration, that an output frequency of the resonator is not deteriorated and improve shock absorption performance of the clock oscillator.

A laterally vibrating bulk acoustic wave (LVBAW) resonator includes a piezoelectric plate sandwiched between first and second metal layers. The second metal layer is patterned into an interdigital transducer (IDT) with comb-shaped electrodes having interlocking fingers. The width and pitch of the fingers of the electrodes determine the resonant frequency. A combined thickness of the first and second metal layers and the piezoelectric layer is less than the pitch of the interlocking fingers.

An integrated circuit may include oscillator circuitry having a resonator formed from fin field-effect transistor (FinFET) devices. The resonator may include drive cells of alternating polarities and sense cells interposed between the drive cells. The resonator may be connected in a feedback loop within the oscillator circuitry. The oscillator circuitry may include an amplifier having an input coupled to the sense cells and an output coupled to the drive cells. The oscillator circuitry may also include a separate inductor and capacitor based oscillator, where the resonator serves as a separate output filter stage for the inductor and capacitor based oscillator.

In an example, a system includes a BAW resonator. The system also includes a first heater configured to heat the BAW resonator, where the first heater is controlled by a first control loop. The system includes a circuit coupled to the BAW resonator. The system also includes a second heater configured to heat the circuit, where the second heater is controlled by a second control loop.