A reference generation circuit provided according to an aspect of the present invention generates a reference potential at different levels in the hold phase of different cycles in an input path of a switched capacitor differential amplifier. In an embodiment, for each hold phase, the reference generator provides the reference potential with a magnitude that tracks the magnitude of the input signal applied in a corresponding (preceding) sample phase. In case of a single-ended output, the reference potential generated for each hold phase equals the magnitude of one of the inputs on the differential input path. As a result, the common mode voltage at the input terminals of an operational amplifier contained in the switched capacitor differential amplifier is maintained at a desired level.