An apparatus for digital error correction in a successive approximation (SAR) analog to digital converter (ADC) includes a binary weighted digital to analog converter (DAC) which can be virtually divided into multiple sub-DACs for redundancy insertion; and a comparator configured to compare the analog input with a DAC level corresponding to digital. The apparatus further includes a register and control logic unit configured to control a switching operation for DAC and to add output codes obtained from sub-DACs to output the added code as a final A/D converted code.