The present disclosure relates to the preparation of acrylate, alkacrylate, allyl, and polycarbonate derivatives of hydroxy ketal esters, and uses thereof. In step S22, it is judged whether or not the quantization value Qref obtained in step S21 is smaller than a predetermined minimum quantization value Qmin. Based on the orthogonal subgrouping, most significant bit comparitors, instead of full-scale comparitors, are used to compare cross-correlations for each subgroup. The sub-booster boosts a voltage in response of the first control signal.