On-line estimation of the integral non-linear errors in analogue-to-digital converters without histogram evaluation

An adaptive digital built-in self-test (BIST) for the static characterisation of analogue-to-digital converters (ADCs) has been developed in this work. The proposed technique performs a blind and accurate estimation of the integral non-linearity (INL) of the ADC under test (ADCUT) without affecting to the normal converter operation, using any test stimuli or replicated hardware. The practical implementation of the BIST technique implies no modifications on the analogue section of the ADCUT and uses a very simple low-cost digital logic, which overcomes the classical area overhead of histogram-based approaches for INL measurement.