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: 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: 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: 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: 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: 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: 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: 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: 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: 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 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: A magnetic composite contains metal magnetic particles and a resin. The metal magnetic particles contain at least one Fe-containing crystalline material, and [Formula 1]Bs×?×{log(?×1/D+?×Bs+?)}{circumflex over (?)}??13T, where Bs and D are the saturation flux density in T and the median diameter of crystallites in ?m, respectively, of the crystalline material, ?=14.3, ?=?0.67, ?=752, ?=512, and ?=?815.

Abstract: A vibration device that includes: a fixing part having a flat plate shape; a vibration part having a flat plate shape, the vibration part being disposed around the fixing part as viewed in a normal direction of the fixing part; a coupling part that couples the vibration part and the fixing part and is constructed to elastically deform, the vibration part constructed to be displaced in an orthogonal direction orthogonal to the normal direction of the fixing part with respect to the fixing part; and a vibration film fixed to the vibration part and the fixing part, the vibration film constructed to vibrate the vibration part in the orthogonal direction with respect to the fixing part when an electric signal is applied to the vibration film.

Abstract: A collector layer, a base layer, and an emitter layer that are disposed on a substrate form a bipolar transistor. An emitter electrode is in ohmic contact with the emitter layer. The emitter layer has a shape that is long in one direction in plan view. A difference in dimension with respect to a longitudinal direction of the emitter layer between the emitter layer and an ohmic contact interface at which the emitter layer and the emitter electrode are in ohmic contact with each other is larger than a difference in dimension with respect to a width direction of the emitter layer between the emitter layer and the ohmic contact interface.

Abstract: A soft magnetic material for soft magnetic particles with a high filling rate. The soft magnetic material contains first soft magnetic particles and second soft magnetic particles with a larger average particle size than the first soft magnetic particles. The first soft magnetic particles have an average particle size in the range of 0.5 to 10 ?m, and the first soft magnetic particles have a nonpolar hydrocarbon group on their surfaces.

Abstract: Described are concepts, circuits, systems and techniques directed toward N-phase control techniques useful in the design and control of supply generators configured for use in a wide variety of power management applications including, but not limited to mobile applications.

Abstract: A power factor correction converter that outputs a DC output voltage from an AC input voltage, includes two channels each including a high-side switch and a low-side switch connected in cascade between a positive output terminal and a negative output terminal of the power factor correction converter and with a node between the high-side switch and the low-side switch; an inductor connected to a first terminal of the AC input voltage and the first node; a gate driver connected to the second high-side switch and the second low-side switch; a bootstrap circuit connected to the second node and the gate driver; wherein the second node is connected to a second terminal of the AC input voltage; and the bootstrap circuit is pre-charged at beginnings of negative half-cycles of the AC input voltage.

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 multilayer ceramic capacitor includes a multilayer body including dielectric layers and internal electrodes alternately stacked on one another, and two external electrodes respectively on two end surfaces of the multilayer body. Each of the dielectric layers includes, at a location coincident with an end portion of a respective one of the internal electrodes, a thick-walled portion thicker in a stacking direction than a portion corresponding in position to a middle portion of a main surface of the multilayer body. When viewed in the stacking direction, positions of some of the thick-walled portions of the dielectric layers are out of alignment with positions of a remainder of the thick-walled portions of the dielectric layers.