PURPOSE:To obtain an output signal in phase to an input, by inverting the phase of an input signal and applying it to the 1st integrator and transferring the differece of charge at one period before and at present to the 2nd integrator without inverting the polarity. CONSTITUTION:A switched capacitor K0C inverts the phase of an input signal V1 and applied it to an operational amplifier OP1 of the 1st stage integrator. A switched capacitor K31C inverts the phase of an input signal charge and transfers it to an integration capacitor C2 of the 2nd stage integrator every period, and switched capacitors K32C, K33C transfer the input signal charge sampled one period before to an integration capacitor C2 alternately without polarity inversion in comparison with the K31C and the charge of difference between the value on e period before and prevent value of an input signal V1 is transferred to the integra tion capacitor C2 without polarity inversion. By selecting K31=K32=K33=K3,V2/V1=K3 is obtaned and the polarity of input and output signals is not inverted.
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