Patent ID: 7339512

Claim:
An analog-to-digital converter comprising: an input to receive an input analog signal; a quantizer comprising at least one comparator subcircuit, the comparator subcircuit comprising at least a threshold capacitor switch coupled to the input for sampling the input analog signal during a quantizer sampling phase and switch coupled to a threshold voltage for producing a digital output signal based on a comparison of the sampled input analog signal to the threshold voltage during a comparison period; and a residue generator coupled to the quantizer, the residue generator comprising a plurality of reference capacitors and a feedback capacitor switch coupled to the input, for sampling the input analog signal during a reference generator sampling phase different from the quantizer sampling phase, said reference capacitors being also switched coupled to a plurality of reference voltages based on settings received from the quantizer during an amplify phase and said feedback capacitor wrapping around an op-amp during said amplify phase, for producing a residue analog output signal, residue generator sampling characteristics substantially matching quantizer sampling characteristics.