PURPOSE: To realize the filter suitable up to high frequency region, by containing a bipolar chip including operational amplifiers and MOS chip including switch group and driving circuit driving the switch group, in one IC package.

CONSTITUTION: A plurality of operational amplifiers 11, 11' are formed in a bipolar chip 2, and power supply of +, 0, - is fed externally from power supply terminals 12, 13, 14. The - and + inputs and outputs are connected to the switch group of MOS chip 1 with the internal connection of IC. The switches 15, 17, 20 are driven with a driving circuit 33 in the timing 1 and switches 16, 18, 19 are in the timing 2 to be allowed to contact. Further, when an external capacitor is connected to terminals 23, 24, it is operated as voltage inverter switch when viewed from the terminals 21(+) and 22(-) together with the amplifier 11.