Receiver and composite component having local oscillator components and mixing circuit integrally formed on semiconductor substrate

摘要

A receiver and a composite component for preventing noise produced by sneaking of a local oscillation signal. An FM receiver comprises a high-frequency amplifier circuit 11 , a mixing circuit 12 , a local oscillator 13 , intermediate-frequency filters 14 and 16 , an intermediate-frequency amplifier circuit 15 , a limit circuit 17 , an FM detection circuit 18 , and a stereo demodulation circuit 19 . The mixing circuit 12 and the local oscillator 13 constitute a one-chip composite component 30 integrally formed on a semiconductor substrate. The frequency of the local oscillation signal is set so that the difference of frequency between the local oscillation signal and a modulated wave signal may be smaller than the occupied bandwidth of the modulated wave signal.