Integral Non-Linearity (INL) is defined as the maximum vertical difference between the actual and the perfect curve.
INL can be interpreted as a sum of DNLs. E.g. several consecutive negative DNLs raise the actual curve above the perfect curve as shown in Figure 1. Negative INLs indicate that the actual curve is below the perfect curve.
The maximum and minimum INL are measured using the same ramp input voltage as in DNL measurement. Record the deviation at each conversion step midpoint and report the most positive and negative deviations as maximum and minimum INL.