A filter circuit includes: a wiring pattern provided in an upper wiring layer of a printed circuit board, a wiring pattern provided in a lower wiring layer of the printed circuit board, a wiring pattern extending from one end of the wiring pattern, a wiring pattern provided so as to partially face the wiring pattern in the upper wiring layer, a bypass capacitor provided in the upper wiring layer and connected to the wiring pattern and a ground conductor surface, a via connecting one end of the wiring pattern and the wiring pattern, and a via connecting the wiring pattern and the wiring pattern. A structure including the wiring pattern, the via, and the wiring pattern faces a structure including the via and the wiring pattern.

An LC filter includes an input terminal, an output terminal, a multilayer body, plate electrodes, connection electrodes connecting the plate electrodes, capacitor electrodes, and a inductor vias. Each of the capacitor electrodes opposes the plate electrode. One end of an inductor via is connected with the input terminal with a capacitor electrode interposed therebetween. Another end of the inductor via is connected to an intermediate point of a connection electrode. An inductor via is connected between the plate electrode and a capacitor electrode. An inductor via is connected between the plate electrode and a capacitor electrode. One end of an inductor via is connected with the output terminal with a capacitor electrode interposed therebetween. Another end of the inductor via is connected to an intermediate point of a connection electrode.

A filter device includes an input terminal, an output terminal, a main body, a common electrode provided to the main body, a ground terminal, and LC parallel resonators connected to the common electrode and the ground terminal. Each LC parallel resonator includes a capacitor, a first via, and a second via. One end of the first via is connected to the common electrode, and another end thereof is connected to the ground terminal through the capacitor. One end of the second via is connected to the common electrode, and another end thereof is connected to the ground terminal without through the capacitor. The second via is connected between portions of the common electrode to which the first vias of two adjacent resonators are connected.

A filter circuit that secures the steepness from a pass range to an attenuation range while maintaining a wide-band transmission characteristic and a filter device including this filter circuit are formed. A filter circuit includes a first filter and a second filter. The first filter is a filter including an LC circuit in which a first frequency band is a pass band and a frequency band not higher than the first frequency band is an attenuation band. The second filter is a filter that attenuates a second frequency band within the first frequency band by using an attenuation pole produced by a resonance or an antiresonance of an acoustic wave resonator. Further, the first filter is placed closer to an antenna terminal than the second filter.

A multilayer electronic device may include a plurality of dielectric layers and a signal path having an input and an output. An inductor may include a conductive layer formed on one of the plurality of dielectric layers and may be 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. The inductor may include an outer perimeter that includes a first straight edge facing outward in a first direction and a second straight edge parallel to the first straight edge and facing outward in the first direction. The second straight edge may be offset from the first straight edge by an offset distance that is less than about 500 microns and less than about 90% of a first width of the inductor in the first direction at the first straight edge.

A wiring board with a filter circuit includes an insulating base, a conductor pattern, and a filter circuit. The conductor pattern is provided on the insulating base and defines the filter circuit. The insulating base includes an intermediate member, and first through third end members connected to the intermediate member. A first external connection terminal is provided on the first end member, and is disposed on a first end of the conductor pattern in the signal transmission direction. A second external connection terminal is provided on the second end member, and is disposed on a second end of the conductor pattern in the signal transmission direction. A first ground connection terminal that grounds the filter circuit is provided on the intermediate member. A second ground connection terminal that grounds the filter circuit is provided on the third end member.

A band pass filter includes parallel resonators. An inductor of a first parallel resonator at an intermediate stage is divided into a first inductor and a second inductor connected in parallel with each other. The first inductor and an inductor of a second parallel resonator are in magnetic coupling with each other, and the second inductor and an inductor of a third parallel resonator are in magnetic coupling with each other.

An electronic component includes a second inductor including a second inductor conductor that includes a first coupling portion electrically coupled to a second capacitor conductor and a second coupling portion electrically coupled to a second ground conductor, and when viewed in a plan view from a lamination direction, a first region surrounded by a first inductor conductor and the second inductor conductor is smaller in area than a second region surrounded by a third inductor conductor layer and the second inductor conductor, and a second region forming portion, which is included in the second inductor conductor and surrounds the second region, and a first region forming portion, which is included in the second inductor conductor and surrounds the first region, are electrically coupled in series in this order on a path from the first coupling portion to the second coupling portion.

A filter device includes a filter including at least one inductor and at least one capacitor, and a stack of a plurality of dielectric layers and a plurality of conductor layers. The plurality of dielectric layers include at least one first dielectric layer formed of a first dielectric material and at least one second dielectric layer formed of a second dielectric material. The plurality of conductor layers include at least one first conductor layer in contact with the at least one first dielectric layer, and at least one second conductor layer in contact with the at least one second dielectric layer. The temperature coefficient of resonant frequency of the first dielectric material has a positive value. The temperature coefficient of resonant frequency of the second dielectric material has a negative value.

A filter includes a body and first and second filters with pass bands different from each other. In the body, an inductor of the first filter is in a first range, and an inductor of the second filter is in a second range. The inductor in the first filter is a vertical coil including a plate electrode and a via extending in a normal direction of the body. In the second filter, the inductor facing the first range is a planar coil with a winding axis in the normal direction of the body. As seen in plan view in the normal direction of the body, an imaginary line from an extending-direction center of the plate electrode of the first filter in a direction perpendicular or substantially perpendicular to the extending direction does not intersect with the inductor of the second filter.