Patent ID: 8223059

Claim:
A switched-capacitor input circuit which receives an analog input signal, and samples and holds the analog input signal, comprising: a differential amplifier; a first capacitor, one terminal of the first capacitor being connected to a non-inverting input terminal of the differential amplifier; a second capacitor, one terminal of the second capacitor being connected to an inverting input terminal of the differential amplifier; a first switch configured to connect the other terminal of the first capacitor to one of a first reference voltage and a second reference voltage; a second switch configured to connect the other terminal of the second capacitor to one of the first reference voltage and the second reference voltage; and a third switch configured to connect the other terminal of the first capacitor to the other terminal of the second capacitor, wherein upon sampling, the first switch connects the other terminal of the first capacitor to the first reference voltage, and the second switch connects the other terminal of the second capacitor to the second reference voltage, and upon holding, the third switch connects the other terminal of the first capacitor to the other terminal of the second capacitor.