Patent ID: 8847699

Claim:
A composite component comprising: a duplexer; and a circuit substrate on which the duplexer is mounted; wherein the duplexer includes: a first external electrode, a second external electrode and a third external electrode; a first filter that outputs a signal input from the first external electrode to the second external electrode; and a second filter that outputs a signal input from the third external electrode to the first external electrode; and the circuit substrate includes: a substrate body that includes a first main surface and a second main surface, the duplexer being mounted on the first main surface; a fourth external electrode, a fifth external electrode, and a sixth external electrode that are provided on the first main surface and to which the first external electrode, the second external electrode and the third external electrode are connected, respectively; a seventh external electrode, an eighth external electrode, and a ninth external electrode that are provided on the second main surface; a first signal path that connects the fourth external electrode and the seventh external electrode, a second signal path that connects the fifth external electrode and the eighth external electrode, a third signal path that connects the sixth external electrode and the ninth external electrode; and a first ground conductor that is embedded in the substrate body and overlaps with a mounting area so as to contain the mounting area where the duplexer is mounted, in a planar view seen from a normal direction of the first main surface, wherein in the planar view seen from the normal direction of the first main surface, at least one of the first signal path, the second signal path and the third signal path extends from an inside of the mounting area to an outside of the mounting area between the first main surface and the first ground conductor, passes through the outside of the mounting area, and is connected to the seventh external electrode, the eighth external electrode and the ninth external electrode.