Integral nonlinearity (acronym INL) is a commonly used measure of performance in digital-to-analog (DAC) and analog-to-digital (ADC) converters.
This measurement is performed after offset and gain errors have been compensated.
[1] The ideal transfer function of a DAC or ADC is a straight line.
The INL measurement depends on what line is chosen as ideal.
is defined as the deviation of the mid-points of the quantization steps between the ideal and real transfer function.