– A new approach for diagnostic analysis of static errors in multi-step ADC based on the steepestdescent method is proposed. To set initial data, estimate the parameter update and to guide the test, dedicated sensors have been designed. The information obtained through monitoring process variations is re-used and supplement the circuit calibration. The technique also allows the test procedure to test only for the most likely group of faults induced by a manufacturing process. The implemented design-for-test approach permits circuit reconfiguration in such a way that all sub-blocks are tested for their full input range allowing full observability and controllability of the device under test.