The, present application provides a filtering circuit and a. TV antenna amplifier, the filtering circuit includes a switching module, and the switching module includes a control unit and at least two filtering units. The present application switchably render one of the at least two filtering units conductive through the control unit, and filter the signals of different frequencies in the input signals through the at least two filtering units, so that different filtering units can be switched according to the filtering requirements of the frequency signal in different regions, which makes it a wide application range.

A multilayer substrate includes a stacked body, coil conductor patterns, and a connection conductor pattern. The stacked body includes insulating layers. A first coil conductor pattern is provided on the front surface of an insulating layer and has a wound shape including outer and inner end portions. A second coil conductor pattern is provided on the front surface of the insulating layer and includes an end portion. The connection conductor pattern is provided in the stacked body, and connects the coil conductor patterns. The outer end portion is connected to a terminal conductor on a back surface of the stacked body. The end portion of the second coil conductor pattern is connected to the terminal conductor on the back surface of the stacked body. The first coil conductor pattern extends parallel or substantially parallel to the second coil conductor pattern along an outer periphery of the second coil conductor pattern.

An LC composite component includes a magnetic substrate with magnetism, a magnetic layer with magnetism, inductors, capacitors, and core parts with magnetism. The magnetic substrate includes a first surface and a second surface on a side opposite to the first surface. The magnetic layer is disposed to face the first surface of the magnetic substrate. The inductors and the capacitors are disposed between the first surface of the magnetic substrate and the magnetic layer. The core parts are disposed between the first surface of the magnetic substrate and the magnetic layer and connected to the magnetic layer. The thickness of the core part is 1.0 or more times the thickness of the magnetic layer, the thickness of the magnetic substrate is 1.0 or more times the thickness of the magnetic layer.

A multilayer filter may include a signal path having an input, an output, and a conductive layer overlying at least one of a plurality of dielectric layers. The conductive layer may be elongated in the first direction and may have a first edge aligned with the first direction and a second edge parallel with the first edge. The conductive layer may include a protrusion extending in the second direction and having an end edge that is parallel with the first edge and offset from the first edge in the second direction by a protrusion length that is greater than about 50 microns. The multilayer filter may include an inductor that is electrically connected at a first location with the signal path and electrically connected at a second location with at least one of the signal path or a ground.

A directional coupler includes a main line through which a signal is transmitted, first and second sub-lines that are selectively coupled to the main line, and a common output port that outputs a detection signal generated by the signal transmitted through the main line, wherein a first degree of coupling between the main line and the first sub-line is different than a second degree of coupling between the main line and the second sub-line.

A semiconductor package is provided. The semiconductor package includes a semiconductor die, a stack of polymer layers, redistribution elements and a passive filter. The polymer layers cover a front surface of the semiconductor die. The redistribution elements and the passive filter are disposed in the stack of polymer layers. The passive filter includes a ground plane and conductive patches. The ground plane is overlapped with the conductive patches, and the conductive patches are laterally separated from one another. The ground plane is electrically coupled to a reference voltage. The conductive patches are electrically connected to the ground plane, electrically floated, or electrically coupled to a direct current (DC) voltage.

An integrated passive die includes a substrate, an input node, an output node, and RF filtering circuitry. The RF filtering circuitry includes a number of LC tank circuits coupled between the input node and the output node. Each one of the LC tank circuits include an inductor and a capacitor. The inductor is formed by a metal trace over the substrate. The capacitor is coupled in parallel with the inductor over the substrate. The inductor and the capacitor are provided such that a resonance frequency of the combination of the inductor and the capacitor is less than a self-resonance frequency of the inductor.

A high-power, frequency-tunable, harmonic filtering system for multiple operating frequencies includes a first SPMT switch circuitry, a second SPMT switch circuitry, and high-power, frequency-tunable harmonic filters (HFHFs). The first SPMT single-pole terminal is configured to receive a high-power RF input signal. The second SPMT single-pole terminal is configured to output a high-power RF output signal. Each of the HFHFs is connected to a respective one of the first SPMT multi-throw terminals and a respective one of the second SPMT multi-throw terminals. Each of the HFHFs is interposed between the respective first and second multi-throw terminals along a respective RF signal pathway between them. Each operating frequency is associated with one of the HFHFs. The respective operating frequency is associated with one of multiple cutoff frequencies of the respective HFHF. A frequency response of each of the HFHF is tunable to multiple cutoff frequencies in accordance with selection of respective shunt capacitances selectable under control of a controller.

A resonant element includes first, second, and third plane electrodes, a first via electrode defining a first inductor, a second inductor, and a third inductor. The first via electrode connects the first plane electrode and the second plane electrode, and each of the second inductor and the third inductor connects the first plane electrode and the third plane electrode. The third plane electrode defines a first capacitor together with the second plane electrode, the second inductor includes second via electrodes, and the third inductor includes third via electrodes. Each of the second via electrodes and the third via electrodes is a columnar conductor extending in the extending direction of the first via electrode.