In a first approach, a reconfigurable radio frequency (RF) filtering module includes a phase-change material (PCM) RF switch bank and an RF filter bank. Each RF filter in the RF filter bank is capable to be engaged and disengaged by a PCM RF switch in the PCM RF switch bank. In a second approach, a tunable RF filter includes PCM RF switches and a capacitor and/or an inductor. Each of the capacitor and/or inductor is capable to be engaged and disengaged by at least one PCM RF switch of the PCM RF switches. In a third approach, an adjustable passive component includes multiple segments and a PCM RF switch. A selectable segment in the multiple segments is capable to be engaged and disengaged by the PCM RF switch. In all approaches, each PCM RF switch includes a PCM and a heating element transverse to the PCM.

Compensation of on-die inductive parasitics in ladder filters through negative mutual inductance between ground inductors is disclosed herein. An exemplary ladder filter includes a primary arm of series resonators and two or more shunt resonator arms connecting nodes between the series resonators to ground. The resonators of the ladder filter are disposed over a semiconductor substrate, to form a circuit die. Constructed ladder filter dice may fail to achieve design filter rejection due to inductive parasitics (e.g., undesired magnetic induction between components). A first shunt arm and a second shunt arm are provided with mutual negatively coupled inductors in order to compensate for these parasitics and improve filter performance.

An integrated circuit (IC) device includes a first resistive strip having an input terminal and an output terminal. The IC device further includes a second resistive strip having a terminal coupled to a voltage. The second resistive strip may be coplanar with the first resistive strip. The IC device further includes a capacitor formed by the first resistive strip and the second resistive strip.

An inductor device includes a first trace, a second trace, and a capacitor. The first trace includes at least two sub-traces. One terminal of each of the at least two sub-traces are coupled to each other at a first node. The second trace includes at least two sub-traces. One terminal of each of the at least two sub-traces are coupled to each other at a second node. The capacitor is coupled to the firs node and the second node.

An inductor device includes first trace, second trace, third trace, fourth trace, first capacitor, and second capacitor. One terminal of each of the at least two sub-traces of first trace are coupled to each other at first node. One terminal of each of the at least two sub-traces of second trace are coupled to each other at second node. One terminal of third trace is coupled to second trace, and another terminal of third trace is coupled to first input/output terminal. One terminal of fourth trace is coupled to first trace, and another terminal of fourth trace is coupled to second input/output terminal. First capacitor is coupled to first node and second node. Second capacitor is coupled between firs node and first input/output terminal, or coupled between first node and second input/output terminal, or coupled between first input/output terminal and second input/output terminal.

Embodiments of the present invention provide an inductively coupled filter and a WiFi module. The inductively coupled filter includes a first circuit, where the first circuit is disposed on a first substrate; and a second circuit, where the second circuit is disposed on a second substrate; and the first substrate and the second substrate are disposed opposite to each other, so that a coil inductor in the first circuit and a coil inductor in the second circuit form a mutual induction structure. In the inductively coupled filter in the embodiments of the present invention, the coil inductors are disposed on two substrates respectively. This can reduce an area occupied by the inductively coupled filter on each package substrate.

A filter component having an ESD protection function that includes a mounting inductor component and a base board. An ESD protection element and a capacitor are formed in the base board, which includes a semiconductor substrate, and front and back rewiring layers. First and second mounting component connection terminal conductors to which the mounting inductor component is connected are formed on an outer surface of the front rewiring layer. Moreover, a first, second and third external connection terminal conductors are formed on an outer surface of the back rewiring layer. The ESD protection element is formed in the semiconductor substrate and the capacitor is formed in one of the front rewiring layer or the back rewiring layer.

Compensation of on-die inductive parasitics in ladder filters through negative mutual inductance between ground inductors is disclosed herein. An exemplary ladder filter includes a primary arm of series resonators and two or more shunt resonator arms connecting nodes between the series resonators to ground. The resonators of the ladder filter are disposed over a semiconductor substrate, to form a circuit die. Constructed ladder filter dice may fail to achieve design filter rejection due to inductive parasitics (e.g., undesired magnetic induction between components). A first shunt arm and a second shunt arm are provided with mutual negatively coupled inductors in order to compensate for these parasitics and improve filter performance.

A wideband impedance matching network comprises a fundamental output MN including a first portion and a second portion and a harmonic compensation MN including a harmonic MN portion and a harmonic MN backside-via inductor formed on an outer surface of a harmonic MN backside via hole penetrating through a semiconductor substrate. The first portion, the second portion and the harmonic MN portion are formed on the semiconductor substrate. A second terminal of the first portion and a first terminal of the second portion are connected to an RF output terminal. A first terminal of the harmonic MN portion and a first terminal of the first portion are connected to an RF input terminal. A second terminal of the harmonic MN portion is connected to a first terminal of the harmonic MN backside-via inductor. A second terminal of the harmonic MN backside-via inductor is grounded.

A trifilar transformer comprising: a first winding; a second winding; and a third winding, wherein one winding is mutually coupled to each of the other two windings, and wherein said other two windings are substantially not coupled to each other. At least one of the first winding, the second winding and the third winding may comprise a figure-of-eight winding, e.g. a clockwise loop and an anti-clockwise loop. In some embodiments, the trifilar transformer may comprise: a first winding; a second winding concentric or interwound with the first winding; and a third winding formed from a first winding part in series with a second winding part, the first winding part having a shape corresponding to the first winding and the second winding part having a shape corresponding to the second winding.