a circuit for testing an analog - digital converter includes : a subtracter which receives a converted value having a plurality of bits outputted from the analog - digital converter and an expected value having a plurality of bits , the subtracter calculating a difference value having a plurality of bits between the converted value and the expected value ; and a logical operation circuit which receives the difference value , the logical operation circuit performing an exclusive - nor operation between adjacent bits in the plurality of bits constituting the difference value , thereby outputting an exclusive - nor value having a plurality of bits .