Patent ID: 8008968

Claim:
An apparatus comprising: a first amplifier stage including: a first preamplifier having a plurality of input terminals and an output terminal, wherein at least one of the input terminals of the first preamplifier receives an input signal for the first amplifier stage; a first output amplifier having an input terminal and an output terminal, wherein the input terminal of the first output amplifier is coupled to the output terminal of the first preamplifier; a first switch that is coupled between the output terminal of the first output amplifier and at least one of the input terminals of the first preamplifier; and a first capacitor that is coupled to the first switch; and a second amplifier stage including: a second preamplifier having a plurality of input terminals and an output terminal, wherein at least one of the input terminals is coupled the output terminal of the first preamplifier stage; a second output amplifier having an input terminal and an output terminal, wherein the input terminal of the second output amplifier is coupled to the output terminal of the second preamplifier; a second switch that is coupled between the output terminal of the second output amplifier and at least one of the input terminals of the second preamplifier; and a second capacitor that is coupled to the second switch.