Abstract: A transmission line includes an element body and a signal conductor layer in the element body and having a linear shape. The transmission line includes a first, second, and third impedance sections, an impedance conversion section, and a reflection section. The second impedance section, the reflection section, the first impedance section, the impedance conversion section, and the third impedance section are positioned in this order along the signal conductor layer. Characteristic impedance of the first impedance section is lower than characteristic impedance in the second impedance section and characteristic impedance in the third impedance section. A change amount of characteristic impedance per unit length in the reflection section is larger than a change amount of characteristic impedance per unit length in the impedance conversion section.

Abstract: In a built-in coil substrate, coil conductor patterns are provided on insulating base materials. Coil interlayer connection conductors, which provide interlayer connection between the coil conductor patterns, are provided on the insulating base materials and made of conductive paste. First and second external electrodes are provided on a first principal surface of a multilayer body. One of the coil conductor patterns is connected to the first external electrode by first-external-electrode connection conductors made of the conductive paste. Another one of the coil conductor patterns is connected to the second external electrode by a second-external-electrode connection conductor. The second-external-electrode connection conductor is a metal film provided in a through hole that extends through the multilayer body in a stacking direction in which the insulating base materials are stacked.

Abstract: A multilayer substrate includes a base including insulating layers stacked on one another, a first principal surface, and a second principal surface, a heat transfer member extending through a first insulating layer nearest to the first principal surface, a second coefficient of thermal conductivity of a material of the heat transfer member is higher than a first coefficient of thermal conductivity of a material of the insulating layers, a first metal film adhered to the first principal surface, the first metal film overlapping the heat transfer member when viewed from the layer stacking direction, and a first joining member disposed between the heat transfer member and the first metal film and being made of a material with a coefficient of thermal conductivity which is higher than the first coefficient of thermal conductivity of the material of the insulating layers.

Abstract: A transmission line includes, in a stacked insulator in which insulator layers are stacked, a first transmission line portion including a first ground conductor pattern, a second ground conductor pattern, and a first signal conductor pattern, and a second transmission line portion including a third ground conductor pattern, a fourth ground conductor pattern, and a second signal conductor pattern. The first signal conductor pattern extends along the second signal conductor pattern. The first ground conductor pattern and the third ground conductor pattern are provided on different insulator layers and at least partially overlap each other in a plan view.

Abstract: A transmission line includes, in a stacked insulator in which insulator layers are stacked, a first transmission line portion including a first ground conductor pattern, a second ground conductor pattern, and a first signal conductor pattern, and a second transmission line portion including a third ground conductor pattern, a fourth ground conductor pattern, and a second signal conductor pattern. The first signal conductor pattern extends along the second signal conductor pattern. The first ground conductor pattern and the third ground conductor pattern are provided on different insulator layers and at least partially overlap each other in a plan view.

Abstract: A transmission line includes, in a stacked insulator in which insulator layers are stacked, a first transmission line portion including a first ground conductor pattern, a second ground conductor pattern, and a first signal conductor pattern, and a second transmission line portion including a third ground conductor pattern, a fourth ground conductor pattern, and a second signal conductor pattern. The first signal conductor pattern extends along the second signal conductor pattern. The first ground conductor pattern and the third ground conductor pattern are provided on different insulator layers and at least partially overlap each other in a plan view.

Abstract: A multilayer substrate includes a base including insulating layers stacked on one another, a first principal surface, and a second principal surface, a heat transfer member extending through a first insulating layer nearest to the first principal surface, a second coefficient of thermal conductivity of a material of the heat transfer member is higher than a first coefficient of thermal conductivity of a material of the insulating layers, a first metal film adhered to the first principal surface, the first metal film overlapping the heat transfer member when viewed from the layer stacking direction, and a first joining member disposed between the heat transfer member and the first metal film and being made of a material with a coefficient of thermal conductivity which is higher than the first coefficient of thermal conductivity of the material of the insulating layers.

Abstract: In a built-in coil substrate, coil conductor patterns are provided on insulating base materials. Coil interlayer connection conductors, which provide interlayer connection between the coil conductor patterns, are provided on the insulating base materials and made of conductive paste. First and second external electrodes are provided on a first principal surface of a multilayer body. One of the coil conductor patterns is connected to the first external electrode by first-external-electrode connection conductors made of the conductive paste. Another one of the coil conductor patterns is connected to the second external electrode by a second-external-electrode connection conductor. The second-external-electrode connection conductor is a metal film provided in a through hole that extends through the multilayer body in a stacking direction in which the insulating base materials are stacked.

Abstract: A transmission line includes, in a stacked insulator in which insulator layers are stacked, a first transmission line portion including a first ground conductor pattern, a second ground conductor pattern, and a first signal conductor pattern, and a second transmission line portion including a third ground conductor pattern, a fourth ground conductor pattern, and a second signal conductor pattern. The first signal conductor pattern extends along the second signal conductor pattern. The first ground conductor pattern and the third ground conductor pattern are provided on different insulator layers and at least partially overlap each other in a plan view.