USAGE OF ADDITIVE ITERATIVE METHOD FOR CORRECTION OF ADC ERRORS IN LSB REGION
Additive iterative method (AIM) could be used for automatic correction of a measurement transducer error. The method is suitable for suppression of errors of analog-to-digital converters (ADC). But quantization error represents limitation for correction process if total measurement error less than 0.5 LSB of ADC is desired. For elimination of this restriction combination of AIM with non-subtractive dithering (ND) is proposed in this paper and the principle of combination of both techniques is described. Inverse element (IE) is fundamental part of a measurement channel with AIM. Analysis of IE design based on pulse width modulation signal is described for application with single-chip microcontroller. To achieve precise processing of signal from IE technique similar to deterministic dithering could be employed which enables faster IE response. For resolution improvement of measured signal processing in the initial step of correction ND with stochastic dither is suggested. From the dependency of root mean squared error on dither dispersion optimal dither dispersion is found.