Abstract: An electronic component includes a first insulator layer including thereon a first conductor pattern to define an inductor and a first electrode pattern to define a capacitor, and a second insulator layer including thereon a second conductor pattern to define the inductor and a second electrode pattern to define the capacitor. The first and second electrode patterns face each other across the second insulator layer to define the capacitor, and the second conductor pattern is electrically connected to the first conductor pattern along the first conductor pattern.

Abstract: An electronic component includes a wiring substrate, surface mount devices mounted on a front surface of the wiring substrate, and a shield plate fixed on a side adjacent to top surfaces of the surface mount devices. The shield plate includes a magnetic ceramic sintered sheet and a first metal film. The magnetic ceramic sintered sheet includes a first main surface and a second main surface. The first metal film is disposed on the first main surface of the magnetic ceramic sintered sheet.

Abstract: In a structure for mounting a shielded module on a printed wiring board, the shielded module includes a mounting substrate, a shielding layer, and a solder layer. Electronic components are mounted on a main surface of the mounting substrate. The shielding layer is provided in an area from above the mounting substrate to a side surface of the mounting substrate and covers the electronic components. The solder layer is provided on a side surface of the shielding layer. The shielding layer is connected to a surface electrode located on the printed wiring board via the solder layer. The surface of the solder layer is depressed.

Abstract: In a structure for mounting a shielded module on a printed wiring board, the shielded module includes a mounting substrate, a shielding layer, and a solder layer. Electronic components are mounted on a main surface of the mounting substrate. The shielding layer is provided in an area from above the mounting substrate to a side surface of the mounting substrate and covers the electronic components. The solder layer is provided on a side surface of the shielding layer. The shielding layer is connected to a surface electrode located on the printed wiring board via the solder layer. The surface of the solder layer is depressed.

Abstract: An electronic component includes a wiring substrate, surface mount devices mounted on a front surface of the wiring substrate, and a shield plate fixed on a side adjacent to top surfaces of the surface mount devices. The shield plate includes a magnetic ceramic sintered sheet and a first metal film. The magnetic ceramic sintered sheet includes a first main surface and a second main surface. The first metal film is disposed on the first main surface of the magnetic ceramic sintered sheet.

Abstract: In a multichannel DC-DC converter that reduces radiation noise to a minimum, a wiring line between the coil conductor of a channel having the smallest load current and the switching IC, among the coil conductors defining a plurality of channels, is the longest connection wiring line, such that a channel having the smallest load current is connected to a wiring line that is most likely to radiate noise and radiation noise is reduced to a minimum. A connection wiring line connected to a coil conductor having the largest load current among the plurality of coil conductors is the shortest connection wiring line. A channel having the largest load current is connected to a wiring line that is least likely to radiate noise and, as a result, radiation noise is further reduced.

Abstract: A DC-DC converter module includes a multi-layer substrate, a switching IC, and a coil. The multi-layer substrate includes component mounting electrodes provided on the top surface and an input terminal, an output terminal, and ground terminals provided on the bottom surface. The switching IC switches an input voltage and includes an input electrode, an output electrode, and a ground electrode, and is mounted on the top surface of the substrate by connecting the electrodes to the component mounting electrodes. The coil is arranged within the multi-layer substrate in a spiral shape with an axis extending in the substrate stacking direction. The bottom surface side end of the coil is connected to the input/output electrode of the switching IC.

Abstract: In a multichannel DC-DC converter that reduces radiation noise to a minimum, a wiring line between the coil conductor of a channel having the smallest load current and the switching IC, among the coil conductors defining a plurality of channels, is the longest connection wiring line, such that a channel having the smallest load current is connected to a wiring line that is most likely to radiate noise and radiation noise is reduced to a minimum. A connection wiring line connected to a coil conductor having the largest load current among the plurality of coil conductors is the shortest connection wiring line. A channel having the largest load current is connected to a wiring line that is least likely to radiate noise and, as a result, radiation noise is further reduced.

Abstract: A circuit board comprises a board substrate including a substrate layer formed with a pad on an upper surface thereof, and a metal piece soldered on the pad. At least one through-hole including an internal wall formed with a conductive film is provided at a portion corresponding to the pad on the substrate layer. The through-hole is filled with a predetermined filler for closing at least an open mouth of the through-hole at the upper surface of the substrate layer. The pad is connected integrally with the conductive film on the internal wall of the through-hole.

Abstract: A circuit board comprises a board substrate including a substrate layer formed with a pad on an upper surface thereof, and a metal piece soldered on the pad. At least one through-hole including an internal wall formed with a conductive film is provided at a portion corresponding to the pad on the substrate layer. The through-hole is filled with a predetermined filler for closing at least an open mouth of the through-hole at the upper surface of the substrate layer. The pad is connected integrally with the conductive film on the internal wall of the through-hole.