SEMICONDUCTOR INTEGRATED CIRCUIT FOR FM RECEIVER

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit for FM receiver where the number of connection terminals of external components to obtain an optimum time constant characteristic respectively to a mute circuit and a search stop signal detection circuit is reduced so as to reduce also the number of terminals of an entire IC resulting in realizing downsizing and cost reduction of the IC. SOLUTION: By only switching only resistive components such as resistors R10, R7 of time constant element outputs to allow the mute circuit 11 and the search stop signal detection circuit 15 to obtain optimum time constant characteristics by means of a channel selection control signal received through a channel selection control signal input terminal 17 from an external device such as a microcomputer, a capacitive component such as a capacitor C4 can be used in common without the need for switching. Thus, the capacitive component is supplied to the integrated circuit through a single common terminal TC 1. Then external connection is attained for the capacitive component C4 requiring external connection to obtain the respectively optimum time constant characteristics through the one external connection terminal T1.