Patent ID: 8258409

Claim:
A circuit board comprising: a substrate; a wiring formed on a main surface of the substrate, and including connectors disposed along four side edges of the substrate; and a cover layer extending over the entire main surface of the substrate other than at openings for the connectors, wherein the cover layer is provided with openings for exposing the connectors of the wiring, and the connectors exposed from the openings are covered with a plating film, the connectors of the wiring are positioned in a region surrounding a circuit-element-mounting-region where a circuit element is designed to be mounted, the circuit-element-mounting region being defined on the main surface of the substrate, and on a surface of the wiring, convex portions in the region surrounding the circuit-element-mounting-region are set larger in width than convex portions in a center part of the circuit-element-mounting-region.