Circuit assembly, producing method of the same, distribution unit and bus bar substrate

摘要

A circuit assembly (2) includes a bus bar substrate (20) and a first relay (24), in order to provide a circuit assembly in which a size in height can be reduced in conjunction with maintaining compactness, especially for a small occupation area in plan view by a simple structure. The bus bar substrate (20) includes an electrical power circuit in which plural bus bar layers (30) are stacked alternately through electrical insulation layers (31) at plural levels. Each bus bar layer (20) has plural bus bars (22) arranged on the substantially same plane. The first relay (24) is connected to the electrical power circuit through terminals (24b). The first relay includes the terminals (24b) having contact pieces (24c) to be superposed on the bus bars (22) along a layer surface of the bus bar (22). The contact piece (24c) of at least one of the terminals is joined by resistance welding to a bus bar layer lower than the uppermost bus bar layer. <IMAGE>