Abstract: Electroacoustic devices with a capacitive element and methods for fabricating such electroacoustic devices. An example method includes forming an acoustic device above a first region of a substrate, and forming a capacitive element above a second region of the substrate and adjacent to the acoustic device. The forming of the capacitive element may include forming a protective layer above the substrate where a first portion of the protective layer is above the second region of the substrate and a second portion of the protective layer is above the first region of the substrate, forming a dielectric region above the protective layer, and forming an electrode above the dielectric region. The dielectric region may include a different material than the protective layer.

Abstract: An electronic filter comprises a high pass section (110) and a low pass section (120). The high pass section includes at least one filter stage of a series-connected acoustic resonator (111) and a parallel connected inductor (114). The low pass section comprises at least one filter stage including a series-connected inductor (121) and a parallel connected acoustic resonator (123). The filter is useful for a communication device covering the n79 5G band.

Abstract: Electroacoustic devices with a capacitive element and methods for fabricating such electroacoustic devices. An example method includes forming an acoustic device above a first region of a substrate, and forming a capacitive element above a second region of the substrate and adjacent to the acoustic device. The forming of the capacitive element may include forming a protective layer above the substrate where a first portion of the protective layer is above the second region of the substrate and a second portion of the protective layer is above the first region of the substrate, forming a dielectric region above the protective layer, and forming an electrode above the dielectric region. The dielectric region may include a different material than the protective layer.

Abstract: An electronic filter comprises a high pass section (110) and a low pass section (120). The high pass section includes at least one filter stage of a series-connected acoustic resonator (111) and a parallel connected inductor (114). The low pass section comprises at least one filter stage including a series-connected inductor (121) and a parallel connected acoustic resonator (123). The filter is useful for a communication device covering the n79 5G band.

Abstract: A microphone and a method for operating a Microphone are disclosed. In an embodiment the microphone includes a transducer and a mode controller. The microphone has a normal operating mode (MO) and a collapse mode (M1). The mode controller switches to the collapse mode (M1) when an output signal of the transducer reaches or exceeds a predefined threshold value and switches to the normal operating mode (MO) when the output signal reaches or falls below a predefined further threshold value (S1).

Abstract: A microphone and a method for operating a Microphone are disclosed. In an embodiment the microphone includes a transducer and a mode controller. The microphone has a normal operating mode (MO) and a collapse mode (M1). The mode controller switches to the collapse mode (M1) when an output signal of the transducer reaches or exceeds a predefined threshold value and switches to the normal operating mode (MO) when the output signal reaches or falls below a predefined further threshold value (S1).

Abstract: The invention relates to a band rejection filter comprising a piezoelectric substrate and a serial connection of at least two pi-elements which are arranged on the substrate. The pi-elements respectively comprise at least two electro-acoustic parallel resonators and at least one electro-acoustic serial resonator, and are connected by a first series inductance. Said serial connection comprises, on a first inlet, a second series inductance and on an outlet, a third series inductance. Said resonators have a pole-zero plot of approximately 9% or more.

Abstract: A MEMS microphone having an improved noise performance due to reduced DC leakage current is provided. For that, a minimum distance between a signal line of the MEMS microphone and other conducting structures is maintained. Further, a DC guard structure fencing at least a section of the signal line is provided.

Abstract: The invention relates to a band rejection filter comprising a piezoelectric substrate (S) and a serial connection of at least two pi-elements (Pi1, Pi2) which are arranged on the substrate (S). The pi-elements (Pi1, Pi2) respectively comprise at least two electro-acoustic parallel resonators (RP1, RP2) and (RP3, RP4) and at least one electro-acoustic serial resonator (RS1, RS2), and are connected by a first series inductance (IS1). Said serial connection comprises, on a first inlet, a second series inductance (ISIN) and on an outlet, a third series inductance (ISOUT). Said resonators (RP1, RP2, RP3, RP4, RS1, RS2) have a pole-zero plot of approximately 9% or more.

Abstract: A MEMS microphone having an improved noise performance due to reduced DC leakage current is provided. For that, a minimum distance between a signal line of the MEMS microphone and other conducting structures is maintained. Further, a DC guard structure fencing at least a section of the signal line is provided.

Abstract: A band-stop filter is described herein. The band-stop filter includes a piezoelectric substrate and a plurality of surface wave element (SAW) impedance elements on the substrate. The band-stop filter also includes at least one series branch comprising at least one series resonator having a finger period, and a plurality of parallel branches connected electrically in parallel with the series branch, each parallel branch including at least one parallel impedance element comprising an interdigital transducer and having a finger period. The average finger period of the at least one series resonator is greater than the average finger period of the at least one parallel impedance element.

Abstract: A surface acoustic wave (SAW) filter includes a piezoelectric substrate, and acoustic tracks on the piezoelectric substrate. The acoustic tracks are adjacent and electrically interconnected. The acoustic tracks include electro-acoustic transducers. The electro-acoustic transducers include an input transducer and an output transducer. The SAW filter also includes a shielding structure that is metallic and that is connected to ground. The shielding structure is between the acoustic tracks. The shielding structure shields a first electro-acoustic transducer in a first acoustic track from a second electro-acoustic transducer in a second acoustic track.

Abstract: A band-stop filter is described herein. The band-stop filter includes a piezoelectric substrate and a plurality of surface wave element (SAW) impedance elements on the substrate. The band-stop filter also includes at least one series branch comprising at least one series resonator having a finger period, and a plurality of parallel branches connected electrically in parallel with the series branch, each parallel branch including at least one parallel impedance element comprising an interdigital transducer and having a finger period. The average finger period of the at least one series resonator is greater than the average finger period of the at least one parallel impedance element.

Abstract: Between the two acoustic tracks of a SAW filter constructed on the surface of a piezoelectric substrate, a metallic shielding structure is positioned and connected to ground in order to shield two transducers positioned in different tracks. In this way crosstalk within a filter is prevented and the stop-band selection is improved.