Abstract: Isolators are disposed such that DC magnetic fields of permanent magnets intensity with each other, and thus, the input impedance of non-reciprocal circuits 3a and 3b (regulating means 3) is reduced. Accordingly, the impedance conversion ratio between the output impedance of amplifying means 2 and the input impedance of the regulating means 3 is reduced to be relatively small. Thus, by simplifying the configuration of matching means 4 disposed between the amplifying means 2 and the regulating means 3, the insertion loss of the matching means 4 can be reduced, thereby enhancing the efficiency of a circuit module 1. Additionally, it is possible to dispose the non-reciprocal circuits 3a and 3b close to each other so that the DC magnetic fields of the permanent magnets can intensity with each other, thereby increasing the design flexibility of the circuit module 1 and accordingly reducing the size of the circuit module 1.

Abstract: As a capacitor Cj is connected in parallel to a non-reciprocal circuit 3, in a predetermined frequency band in which a power amplifier 2 is used, or in other words, in a predetermined frequency band used in communication, an input impedance of the non-reciprocal circuit 3 is adjusted and the length of an impedance curve (reflection coefficient S11) at an input terminal P2 of the non-reciprocal circuit 3 can thus be reduced. In addition, an output impedance of the power amplifier 2 and an input impedance of the non-reciprocal circuit 3 can be matched in a broad band through an interstage matching circuit 7 (input matching circuit 6) provided between an output terminal P1 of the power amplifier 2 and the input terminal P2 of the non-reciprocal circuit 3.

Abstract: Isolators are disposed such that DC magnetic fields of permanent magnets intensity with each other, and thus, the input impedance of non-reciprocal circuits 3a and 3b (regulating means 3) is reduced. Accordingly, the impedance conversion ratio between the output impedance of amplifying means 2 and the input impedance of the regulating means 3 is reduced to be relatively small. Thus, by simplifying the configuration of matching means 4 disposed between the amplifying means 2 and the regulating means 3, the insertion loss of the matching means 4 can be reduced, thereby enhancing the efficiency of a circuit module 1. Additionally, it is possible to dispose the non-reciprocal circuits 3a and 3b close to each other so that the DC magnetic fields of the permanent magnets can intensity with each other, thereby increasing the design flexibility of the circuit module 1 and accordingly reducing the size of the circuit module 1.

Abstract: As a capacitor Cj is connected in parallel to a non-reciprocal circuit 3, in a predetermined frequency band in which a power amplifier 2 is used, or in other words, in a predetermined frequency band used in communication, an input impedance of the non-reciprocal circuit 3 is adjusted and the length of an impedance curve (reflection coefficient S11) at an input terminal P2 of the non-reciprocal circuit 3 can thus be reduced. In addition, an output impedance of the power amplifier 2 and an input impedance of the non-reciprocal circuit 3 can be matched in a broad band through an interstage matching circuit 7 (input matching circuit 6) provided between an output terminal P1 of the power amplifier 2 and the input terminal P2 of the non-reciprocal circuit 3.