Patent ID: 7804434

Claim:
A switched-capacitor circuit comprising: an operational amplifier having a first input, a second input, and an output; a holding capacitor having a first side and a second side respectively coupled between the first input and the output of the operational amplifier; one or more sampling capacitors each having a first side and a second side and each provided with respective switches to selectively couple the one or more sampling capacitors to any of first and second voltage sources, a reference voltage, and the holding capacitor; and switching logic configured to control said switches in a repetitive operation cycle, said operation cycle including: a charging phase in which the switching logic selects at least one of the sampling capacitors to be connected at either side thereof to the first and second voltage sources respectively; an equalization phase in which the switching logic connects the first side of the one or more sampling capacitors to the reference voltage to change the voltage on both sides of the sampling capacitors if the first side has a voltage other than the reference voltage; and a sharing phase in which the switching logic connects the one or more sampling capacitors across the holding capacitor for transferring charge from the sampling capacitors to the holding capacitor.