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The paper presents a new method for autocalibration of offsets of internal components in adaptive sub-ranging analog-todigital
converters (ADCs). The adaptive sub-ranging ADCs, like other iterative ADCs, are very sensitive to offsets
caused by technological imperfections. To achieve higher effective resolution in a sub-ranging ADC, offsets should be
accordingly diminished, which is achieved using sophisticated techniques usually causing increase of power
consumption as well as complexity and size of ADC. But the structure of adaptive sub-ranging ADC and the way of
calculation of output codes create a possibility to compensate offsets during conversion of input samples. Moreover,
using the internal digital-to-analog converter (DAC) as a source of calibration signal in the procedure of offsets
estimation and addition of a calibration program in the digital part of the converter, enable automatization and
autonomization (no additional instruments are needed) of the calibration process. Usefulness and limitations of the
proposed solution were confirmed in computer simulations whose main results are presented and discussed in the paper.
Implementation of the proposed solution enables to increase effective resolution of ADCs and simultaneously to weaken
the requirements on acceptable level of offsets of ADC components.
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