An ADC is provided. The ADC includes a plurality of pre-amplifiers, dynamic comparators coupled to the pre-amplifiers, interpolators and an encoder. Each pre-amplifier provides a pair of differential outputs according to a pair of differential analog signals and a first reference voltage and a second reference voltage different from the first reference voltage. Each dynamic comparator provides a first comparing signal and a second comparing signal according to the pair of differential outputs of the corresponding pre-amplifier. Each interpolator provides an interpolating signal according to the first and second comparing signals of two of the dynamic comparators. The encoder provides a digital output according to the interpolating signals. The first and second comparing signals are the same in a reset phase, and the first and second comparing signals are complementary according to the pair of differential outputs of the corresponding pre-amplifier in an evaluation phase.