PURPOSE: To reduce the cost by incorporating a circuit which serves as a bell/ inverse bell filter and incorporating a discrete component as an external element. ;CONSTITUTION: An input signal which is supplied to an input terminal 11 is supplies to an attenuating circuit 14 and one input of an adder 15 through a BPF 13 which can have its Q controlled with a control signal supplied to a Q control terminal 12. The input signal supplied to the input terminal 11 is supplied to an attenuating circuit 16 and a subtracter 17 as well. The output of the attenuating circuit 16 is supplied to the other input of the adder 15. The output of the attenuating circuit 14 is connected to the subtraction input of the subtracter 17. The output signal of the adder 15 is supplied as bell filter signal to a switching circuit 18 and the output of the subtracter 17 is supplied as an inverse bell signal. The switching circuit 18 selects one of those two signals and outputs it to an output terminal 19.;COPYRIGHT: (C)1996,JPO
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