DRIFT-LIKE ERRORS COMPENSATION IN INTELLIGENT CYCLIC A/D CONVERTERS
Konrad Jędrzejewski
Abstract:
The paper presents the results of investigations on elimination of drift-like errors in intelligent cyclic A/D converters, in particular errors caused by drifts (droops) of voltage at the output of sample-and-hold blocks. The proposed solution is based on application of the extended multi-dimensional algorithm, which estimates simultaneously values of the input sample and the drift rate using the drift rate estimates for correction of the input sample codes. Implementation of the extended algorithm in the intelligent cyclic A/D converters requires only insignificant changes in the digital part of the converter and does not increase their production costs. The motivations to these investigations were results of practical realizations of the intelligent cyclic A/D converter in CMOS technology and difficulties in design of a precise sample-and-hold circuit. The results of selected simulation experiments related to analysis of influence of a droop rate on the final performance of the intelligent cyclic A/D converters employing the standard (one-dimensional) and extended algorithms are discussed and compared in the paper.
