PURPOSE: To apply S-Z conversion of a high-order, especially an odd number order filter by designing the capacitor filter so that a linear switched capacitor filter is not provided independently.

CONSTITUTION: Plural switch circuits 1, 8, 9 being the combination of an in- phase switched capacitor and an opposite phase switched capacitor and plural arithmetic circuits 2, 3, 4 are connected alternately. Then switch circuits 5, 6, 7 being parallel connection of capacitors and in-phase switched capacitors are connected to an input-output feedback circuit among the arithmetic circuits 2, 3, 4 and switch circuits 10, 11 being the combination of in-phase switched capacitors and opposite phase switched capacitors are connected between an input terminal and an input of the arithmetic circuits 3, 4. Thus, a 3rd-order switched capacitor filter having a transfer function expressed in a prescribed equation is obtained.