PURPOSE: To realize an optional pole with a comparatively less number of components by providing an inverting switched capacitor coupled between an inverting input of the 1st operational amplifier and an output terminal of the 2nd operational amplifier and a switched capacitor coupled respectively between an inverting input and an output of the 1st and 2nd operational amplifiers.

CONSTITUTION: The 1st and 2nd operational amplifiers 101, 102 are arranged between an input terminal 111 and an output terminal 112 of a filter, an inverting switched capacitor 103 is connected between the input terminal 111 and the inverting input of the operational amplifier 101, a non-inverting switched capacitor 104 and an inverting switched capacitor 105 are connected between the input terminal 111 and the operational amplifier 102, a non-inverting switched capacitor 107 and an inverting switched capacitor 108 are connected in parallel between an output terminal of the operational amplifier 101 and the inverting input of the operational amplifier, and an inverting switched capacitor 106 is connected between the inverting input of the operational amplifier 101 and the output of the operational amplifier 102.