The invention provides a high-precision successive approximation type analog-digital converter and a performance lifting method based on a DNL (dynamic noise limiter). The high-precision successive approximation type analog-digital converter comprises a redundancy weight capacitor array, a comparator, a coding and reconstructing circuit, a weight storage circuit and a control logic circuit, wherein the redundancy weight capacitor array is used for acquiring an input voltage on a sampling stage to generate an output voltage, and realizing voltage addition and subtraction operation by controlling the corresponding weight capacitor of the redundancy weight capacitor array according to the comparator output results on the conversion stage; the comparator is used for comparing the output voltage of the redundancy weight capacitor array; the coding and reconstructing circuit is used for calculating an output code of the successive approximation type analog-digital converter according to the comparator output results and the capacitor weight in the weight storage circuit; the weight storage circuit is used for capacitor weight; the control logic circuit is used for controlling the sampling and conversion stage of the redundancy weight capacitor array. The invention further provides the performance lifting method based on the DNL (dynamic noise limiter). According to the high-precision successive approximation type analog-digital converter provided by the invention, the digital correction of capacitor mismatch errors is realized by adopting the capacitor array with the redundancy weight, and the conversion speed and the linear speed are increased.