Abstract: A circuit assembly includes a circuit board on which a coil is mounted, a heat sink, and a heat spreading plate that is separate from this heat sink. A first insulating adhesive layer is interposed between the circuit board and the heat spreading plate, and the heat spreading plate and the heat sink are fixed by a first fixing hole for a heat sink and a bolt. Accordingly, warping of the circuit board is suppressed.

Abstract: A vehicle-mounted power distribution board includes: a circuit structure including a control circuit board including a conductive path on at least one of a front surface and a back surface, and a plurality of bus bars that is placed on the control circuit board, and that is composed of a plurality of bus bars; and a plurality of electronic components that are mounted to the circuit structure. Some of the plurality of electronic components are semiconductor elements that generate heat when current flows through it, and the other components are low heat resistant electrolytic capacitors and integrated circuits that are influenced by heat transferred from the semiconductor elements. Bus bar non-arrangement regions in which no bus bar is disposed are formed in the circuit structure, and the low heat resistant electrolytic capacitors and the integrated circuits are disposed in the bus bar non-arrangement regions.

Abstract: An electrical junction box that includes a circuit board on which a coil element is installed; a partition wall that surrounds the coil element and separates an installation region on the circuit board on which the coil element is installed from a region around the installation region; a frame that is formed in one piece with the partition wall and surrounds the circuit board; a heat dissipation plate on which the circuit board and the frame are placed; and a cover that covers the circuit board from the frame side, wherein the coil element is fixed to the partition wall using a synthetic resin material, and wherein the frame and the heat dissipation plate are positioned relative to each other through a recess-projection engagement, and the cover is fixed to the heat dissipation plate using screws.

Abstract: An electrical junction box that includes a circuit board on which a coil element is installed; a partition wall that surrounds the coil element and separates an installation region on the circuit board on which the coil element is installed from a region around the installation region; a frame that is formed in one piece with the partition wall and surrounds the circuit board; a heat dissipation plate on which the circuit board and the frame are placed; and a cover that covers the circuit board from the frame side, wherein the coil element is fixed to the partition wall using a synthetic resin material, and wherein the frame and the heat dissipation plate are positioned relative to each other through a recess-projection engagement, and the cover is fixed to the heat dissipation plate using screws.

Abstract: A circuit assembly includes a circuit board on which a coil is mounted, a heat sink, and a heat spreading plate that is separate from this heat sink. A first insulating adhesive layer is interposed between the circuit board and the heat spreading plate, and the heat spreading plate and the heat sink are fixed by a first fixing hole for a heat sink and a bolt. Accordingly, warping of the circuit board is suppressed.

Abstract: Provided is an electrical junction box including: a circuit board that has a mounting surface on which an electronic component is mounted; and a frame in which the circuit board is accommodated. The frame is provided with a board covering portion that covers a part of the electronic component on the mounting surface side, and the board covering portion is provided with a retaining portion that retains the electronic component. Furthermore, it is also possible to provide an outer case that covers the board covering portion from a side opposite to the side on which the circuit board is arranged while overlapping the board covering portion.

Abstract: A vehicle-mounted power distribution board includes: a circuit structure including a control circuit board including a conductive path on at least one of a front surface and a back surface, and a plurality of bus bars that is placed on the control circuit board, and that is composed of a plurality of bus bars; and a plurality of electronic components that are mounted to the circuit structure. Some of the plurality of electronic components are semiconductor elements that generate heat when current flows through it, and the other components are low heat resistant electrolytic capacitors and integrated circuits that are influenced by heat transferred from the semiconductor elements. Bus bar non-arrangement regions in which no bus bar is disposed are formed in the circuit structure, and the low heat resistant electrolytic capacitors and the integrated circuits are disposed in the bus bar non-arrangement regions.