Abstract: Filter devices. A first chip includes a first base, a first piezoelectric membrane having a first thickness, and a first acoustic Bragg reflector sandwiched between the first piezoelectric membrane and the first base. A first interdigital transducer (IDT) of a first solidly-mounted membrane resonator is formed on a surface of the first piezoelectric membrane. A second chip includes a second base, a second piezoelectric membrane having a second thickness less than the first thickness, and a second acoustic Bragg reflector sandwiched between the second piezoelectric membrane and the second base. A second IDT of a second solidly-mounted membrane resonator is formed on a surface of the second piezoelectric membrane. A circuit card is coupled to the first chip and the second chip, the circuit card including at least one conductor for making an electrical connection between the first IDT and the second IDT.

Abstract: A capacitor structure that includes a silicon substrate having a trench structure formed therein; a dielectric disposed over a surface of the trench structure, conformal to the surface of the trench structure; and a filling layer disposed over the dielectric layer and into the trench structure, the filling layer including a conductive layer and a polymer layer.

Abstract: A communication circuit includes a transmission terminal to which a transmission signal is supplied, a first duplexer that has a transmission node, a reception node, and a common node, a first filter that has a first end part electrically connected to the common node of the first duplexer and a second end part electrically connected to an antenna terminal, a first auxiliary output terminal that outputs the transmission signal to an external circuit, an inductor that is part of a second filter and has a first end part and a second end part that is electrically connected to the first auxiliary output terminal, and a first switch that switches the electrical connection destination of the transmission terminal between the transmission node of the first duplexer and the first end part of the inductor.

Abstract: To suppress a decrease in mounting strength of a coil component, a coil component includes a drum core including a winding core portion, and first and second flange portions. The coil component includes a first metal terminal which includes a bonding portion, a connecting portion, and a mounting portion. The bonding portion is bonded to the first flange portion with an adhesive. The mounting portion is closest to the first positive direction side in the first metal terminal and is separated from the first flange portion toward the first positive direction side. The connecting portion connects the bonding and mounting portions. The first flange portion has a facing surface that faces the mounting portion, a bonding surface, and a first inclined surface between the facing and bonding surfaces. The distance from the facing surface increases in a direction parallel to the first axis toward the bonding surface.

Abstract: An amplifier module includes an antenna that includes four power feed points, and four power amplifiers. Output ends of the four power amplifiers are connected to the four power feed points in a one-to-one relationship. The four power feed points are arranged rotationally symmetrically around a center of the antenna when a main surface of the antenna is viewed in plan.

Abstract: An antenna module including a dielectric substrate having a long side and a short side, a ground electrode, a radiating element, a peripheral electrode, and a parasitic element. The radiating element is disposed to face the ground electrode. The peripheral electrode is disposed along the long side of the dielectric substrate and is electrically connected to the ground electrode. The parasitic element is disposed along the short side of the dielectric substrate and is disposed away from the radiating element. The radiating element is configured to emit radio waves in two polarization directions along the long side and the short side of the dielectric substrate. The shortest distance between the radiating element and the parasitic element is greater than the shortest distance between the radiating element and the peripheral electrode.

Abstract: A power amplifier circuit and an LC circuit are included. The power amplifier circuit amplifies a radio frequency signal by switching between the first mode, in which power is amplified by using the envelope tracking system, and the second mode, in which power is amplified by using the average power tracking system. The LC circuit is connected, at its first end, to the power supply path of the power amplifier circuit and that is grounded, at its second end, through a switch circuit. The LC circuit includes a first capacitor and an inductor that is connected in series to the first capacitor. The switch circuit is controlled to be switched off in the first mode and is controlled to be switched on in the second mode.

Abstract: A coil component includes a core including a winding core portion and a first flange portion that is disposed on a first end portion of the winding core portion in a direction in which the winding core portion extends. A first curved portion is formed at a connection between a bottom surface of the winding core portion and the first flange portion. A ratio of a length of the first curved portion in a height direction to a distance in the height direction between the bottom surface and a first terminal electrode is no less than 20% and no more than 60% (i.e., from 20% to 60%).

Abstract: To suppress deformation of a mounting portion, a coil component includes a drum core including a winding core portion, a first flange portion, and a second flange portion. The coil component includes a first metal terminal. The first metal terminal includes a joining portion, a mounting portion, and an extending portion. A first wire end of the first wire is connected to a surface of the joining portion facing a first positive direction. The mounting portion is located closest to the first positive direction in the first metal terminal. The extending portion connects the mounting portion and the joining portion. The extending portion includes a second portion having a thickness dimension smaller than the thickness dimension of the mounting portion.

Abstract: An amplifier circuit includes amplifiers, transformers, and a transmission line. A first end of an input-side coil is connected to an output terminal of the amplifier, a second end of the input-side coil is connected to an output terminal of the amplifier via the transmission line, a first end of an input-side coil is connected to an output terminal of the amplifier, a second end of the input-side coil is connected to the output terminal of the amplifier via the transmission line, a first end of an output-side coil is connected to an output terminal, a second end of the output-side coil is connected to a ground, a first end of an output-side coil is connected to an output terminal, and a second end of the output-side coil is connected to the ground.

Abstract: A coil component includes an element body including a multilayer body in which a first ferrite layer, a first glass layer, and a second ferrite layer are laminated in that order; a coil embedded in the first glass layer; and an outer electrode provided on an outer surface of the element body and electrically connected to the coil. The first glass layer includes regions in which Cu and Mg coexist.

Abstract: A coil component includes a drum core including a winding core portion, and first and second flange portions; and a first metal terminal which includes a bonding portion, a connecting portion, a mounting portion, an extending portion, and a joining portion. The first flange portion includes a main body portion, an end-surface-side protruding portion protruding from an outer end surface of the main body portion and a bottom-surface-side protruding portion protruding from a bottom surface of the main body portion. In a direction parallel to a second axis, a shortest distance from an end of the end-surface-side protruding portion on the second positive direction side to the joining portion is a first distance. A maximum distance from the end of the end-surface-side protruding portion to a side end surface of the end-surface-side protruding portion is a second distance. The first distance is larger than the second distance.

Abstract: Resonator devices, filter devices, and methods of fabrication are disclosed. A resonator device includes a substrate and a single-crystal piezoelectric plate having front and back surfaces. An acoustic Bragg reflector is sandwiched between a surface of the substrate and the back surface of the piezoelectric plate. An interdigital transducer (IDT) is formed on the front surface of the piezoelectric plate. The IDT and the piezoelectric plate are configured such that a radio frequency signal applied to the IDT excites a primary acoustic mode within the piezoelectric plate. The acoustic Bragg reflector comprises alternating SiO2 and diamond layers and is configured to reflect the primary acoustic mode.

Abstract: A method for manufacturing a ceramic substrate that includes forming a mother multilayer body by laminating a ceramic green sheet on a shrinkage suppressing green sheet, the shrinkage suppressing green sheet having a planar shrinkage rate in firing smaller than a planar shrinkage rate in firing of the ceramic green sheet; and forming a recessed portion in the mother multilayer body before firing by pressing a recessed portion formation planned region where the recessed portion is to be formed after firing of the mother multilayer body.

Abstract: An acoustic resonator is fabricated by bonding a first piezoelectric plate to a substrate and spans locations for a first and second cavity in the substrate. A top surface of the first piezoelectric plate is planarized to a first thickness. A bonding layer is formed on the first piezoelectric plate and spans the first and second cavity locations. A second piezoelectric plate is bonded to the bonding layer and spans the first and second cavity locations. A portion of the second piezoelectric plate spanning the second cavity location is etched away to form a first membrane over the first cavity location and a second membrane over the second cavity location. Interdigital transducers are formed on the first and second membranes over the first and second cavity location to form a first and second resonator on the same die.

Abstract: An acoustic resonator includes a piezoelectric plate with a back surface attached to a substrate. An interdigital transducer (IDT) including interleaved fingers is formed on the front surface of the piezoelectric plate, the IDT comprising multiple copies of a unit cell juxtaposed along a length of the IDT. Each unit cell includes a first pitch/mark zone having a first pitch P1 between adjacent fingers and a first mark M1 and a second pitch/mark zone having a second pitch P2 and a second mark M2, where P2 is not equal to P1 and M2 is not equal to M1. A radio frequency signal applied to the IDT causes the first pitch mark zone and the second pitch/mark zone to excite a same shear primary acoustic mode in the piezoelectric plate.

Abstract: An inductor component and a method for manufacturing an inductor component that enables miniaturization of the inductor component. An inductor component includes an annular core; and a coil including a plurality of pin members and wound on the core with neighboring pin members connected to each other. A first pin member and a second pin member both adjacent to each other have a welded part in which an end face of an end part of the first pin member and a peripheral surface of an end part of the second pin member are welded to each other. The welded part is not provided on an outer side edge of the second pin member as viewed from a direction orthogonal to a first plane containing a center line of the end part of the first pin member and a center line of the end part of the second pin member.

Abstract: A three-terminal capacitor includes a main body having a cylindrical or substantially cylindrical shape extending in a first direction and including first and second inner electrodes alternately laminated together with dielectric layers interposed therebetween, a pair of first outer electrodes on two end surfaces of the main body in the first direction and electrically connected to the first inner electrodes, and a second outer electrode electrically connected to the second inner electrodes. The main body includes a projecting portion projecting in a direction perpendicular or substantially perpendicular to the first direction at a position between the pair of first outer electrodes. The second outer electrode is provided on one surface of the projecting portion viewable when viewed in the first direction.

Abstract: A film capacitor that includes a dielectric resin film containing a cured product of a first organic material and a second organic material; and a metal layer on at least one surface of the dielectric resin film. The first organic material contains an organic polymer having a hydroxy group and a benzene ring in a repeating unit; the second organic material contains 4,4?-diphenylmethane diisocyanate, a modified product of 4,4?-diphenylmethane diisocyanate, or a mixture thereof; and 400 ppm to 700 ppm of chlorine ions and 300 ppm to 500 ppm of phosphorus ions are present inside the dielectric resin film.

Abstract: A mesa portion is formed on a substrate. An insulating film including an organic layer is disposed on the mesa portion. A conductor film is disposed on the insulating film. A cavity provided in the organic layer has side surfaces extending in a first direction. A shorter distance out of distances in a second direction perpendicular to the first direction from the mesa portion to the side surfaces of the cavity in plan view is defined as a first distance. A shorter distance out of distances in the first direction from the mesa portion to side surfaces of the cavity in plan view is defined as a second distance. A height of a first step of the mesa portion is defined as a first height. At least one of the first distance and the second distance is greater than or equal to the first height.