A circuit board that includes a substrate that has an upper surface on which a circuit pattern is formed, and a lower surface to which a plurality of bus bars that are spaced apart are fixed; a placement through hole that extends through the upper surface and the lower surface and faces a bus bar of the plurality of bus bars and in which an electronic component is placed; and a terminal conductor foil that protrudes inward into the placement through hole from the lower surface and to which a terminal of the electronic component is connected.