An LC composite component includes a multilayer body including insulating base members that are laminated and include insulating base members on which conductor patterns are provided. Capacitor conductor patterns are provided on insulating base members different from an insulating base member on which a coil conductor pattern is provided, and each include an extending portion overlapping with a line segment connecting a center of a first terminal and a center of a second terminal in a shortest distance as viewed in the lamination direction and projecting portions projecting in directions different from the direction of the line segment, and the projecting portions overlap with linear portions of the coil conductor pattern without overlapping with bent portions thereof as viewed in the lamination direction.

Radio frequency (RF) filters configured to filter undesired signal components (e.g., noise and harmonics) from RF signals are disclosed. In one embodiment, an RF filter includes a first inductor coil having a first winding and a second inductor coil having a second winding and a third winding. The second winding of the second inductor coil is configured to have a first mutual magnetic coupling with the first winding, while the third winding of the second inductor coil is configured to have a second mutual magnetic coupling with the first winding. The second winding is connected to the third winding such that the first mutual magnetic coupling and the second mutual magnetic coupling are in opposition. In this manner, the first inductor coil and the second inductor coil may be provided in a compact arrangement while providing weak mutual magnetic coupling between the first inductor coil and the second inductor coil.

A reactance cancelling radio frequency (RF) circuit array is disclosed. The reactance cancelling RF circuit array includes multiple RF circuits each coupled to one or two adjacent RF circuits by one or two pairs of coupling mediums each having a respective length less than one-quarter wavelength. In one aspect, an RF input signal is first split across the RF circuits and then combined to form an RF output signal. As a result, each RF circuit requires a lower power handling capability to process a portion of the RF input signal. In another aspect, each pair of the coupling mediums can cause reactance cancellation in each reactance-cancelling pair of the RF circuits. By coupling the RF circuits via the coupling mediums and enabling splitting-combining among the RF circuits, it is possible to miniaturize the reactance cancelling RF circuit array for improved performance across a wide frequency spectrum.

A band-pass filter includes a first input/output port, a second input/output port, a first high-pass filter, a first low-pass filter, and a first stub resonator. The first stub resonator includes a first distributed constant line. The first low-pass filter is provided between the first input/output port and the first high-pass filter in the circuit configuration. The first distributed constant line has a first end connected to a first path connecting the first input/output port and the first low-pass filter, and a second end closest to a ground in the circuit configuration.

An LC filter includes a first capacitor electrode connected to one end of a first via conductor and faces a first ground electrode in a laminating direction. A second capacitor electrode is connected to one end of a second via conductor and faces the first ground electrode in the laminating direction. A third capacitor electrode is connected to one end of a third via conductor and faces the first ground electrode in the laminating direction. A fourth capacitor electrode is connected to one end of a fourth via conductor and faces the first ground electrode in the laminating direction. The second capacitor electrode faces each of the first capacitor electrode, the third capacitor electrode, and the fourth capacitor electrode in a direction orthogonal or substantially orthogonal to the laminating direction.

An LC filter includes a first electrode connected to a first via conductor between two ends of the first via conductor, a second electrode connected to a second via conductor between two ends of the second via conductor, a third electrode connected to a third via conductor between two ends of the third via conductor, and a fourth electrode connected to a fourth via conductor between two ends of the fourth via conductor. In a plan view viewed from the laminating direction, the second via conductor and the fourth via conductor are disposed on two sides of a virtual line connecting the first via conductor and the third via conductor, respectively. The second electrode faces the first electrode and the third electrode.

A matching circuit, a radio frequency front-end power amplification circuit, and a mobile communication device are provided. The matching circuit is configurable for the radio frequency front-end power amplification circuit, including a first impedance matcher, a first bandpass filter, a first wave trap, and a first matching unit. An impedance of the first impedance matcher is a first preset impedance at a first frequency, the first bandpass filter is bridged between a front end of the first impedance matcher and ground, the first bandpass filter enables a signal of the first frequency to pass through, and suppresses at least one of a signal of a second frequency and a signal of third harmonic generation of the first frequency. The second frequency is lower than the first frequency. The first wave trap is bridged between a rear end of the first impedance matcher and the ground.

Disclosed are example embodiments of a circuit comprising a first inductor-capacitor (LC) loop, a second LC loop having at least one of a series connection or parallel connection to the first LC loop, and a gyrator coupled between the first LC loop and the second LC loop. In an example, the first LC and the second LC loop each include an inductive element (L) and a capacitive (C) element coupled to each other in series. In another example, the first LC and the second LC loop each include an inductive element (L) and a capacitive (C) element coupled to each other in parallel.

An electronic component includes a first input/output port, a second input/output port, a third input/output port, a first circuit that is a characteristic impedance converter circuit provided between the first input/output port and the second input/output port, a second circuit that is a characteristic impedance converter circuit provided between the first input/output port and the third input/output port, and a third circuit provided between the second input/output port and the third input/output port, the third circuit having a circuit configuration where a complex conjugate relationship is made with each of the first and second circuits.

Embodiments relate to a transformer-based impedance matching network that may dynamically change its characteristic impedance by engaging different inductor branches on a primary side and optionally, on the secondary side. A primary side transformer circuit includes a primary inductor (311) and secondary inductor (321) configured to provide impedance matching over a first frequency band. One or more additional inductor branches (314A, 314B, are switchably coupled to either or both of the primary and secondary inductors to modify the impedance matching characteristics over additional operating frequencies. One or more LC filter branches (321, 322, 326, 327, 336, 330) can be included at the output of the secondary side to filter harmonic frequencies in each of the operating frequency bands.