According to Fig. 7.59, the DNL is given by the difference w(k) - w(r) for
each possible value of the output code k, and the IDL presents the difference s(k)
between the input voltage of both the investigated ADC and the reference ADC.
As the determination of the DNL and IDL at stepwise increasing DC voltage is
extremely time-consuming, particularly for ADCs of more than 8 bit resolution,
the experimental results might strongly be affected by the long-term stability of the
DC voltage source.
As an alternative, thus the following method has been proposed by Steiner in