Patent ID: 8248179

Claim:
A circuit module comprising: a core isolator including: a ferrite; a permanent magnet arranged to apply a direct-current field to the ferrite; a first center electrode that is provided in the ferrite, the first center electrode being connected at one end thereof to an input port and connected at another end thereof to an output port; and a second center electrode that is provided in the ferrite so as to intersect the first center electrode in an insulating manner, the second center electrode being connected at one end thereof to the output port and connected at another end thereof to a ground port; a branch portion that is connected at one end thereof to the output port of the core isolator and is arranged to outputs to a first signal path or a second signal path, a signal outputted from the output port; a first processing circuit that is provided on the first signal path; and a first matching circuit that is provided on the first signal path so as to be connected to a switch terminal on the first signal path side of the branch portion to provide impedance matching between an output impedance of the core isolator and an input impedance of the first processing circuit.