Patent ID: 7126415

Claim:
A switched-capacitor operational amplifier circuit, comprising: an operational amplifier, having an input and an output; a first sampling capacitor; an error capacitor, connected to the first sampling capacitor at a first node, and connected to the input of the operational amplifier; a second sampling capacitor; a feedback capacitor, connected to the second sampling capacitor at a second node; a grounding switch for connecting the first node to a ground potential responsive to a first clock phase; first and second sampling switches, for connecting the first and second sampling capacitors to complementary input voltages responsive to the first clock phase; sampling feedback switches, for connecting the feedback capacitor between the input and output of the operational amplifier through the second node responsive to the first clock phase; a feedback switch, for connecting the output of the operational amplifier to the first sampling capacitor responsive to a second clock phase; and grounding switches, for connecting the feedback capacitor to ground potential responsive to the second clock phase.