To calculate the nonlinearities, usually a commonly used histogram method is applied, in which the input sinusoidal signal has a range exceeding the full scale. But in some cases it is required to determine the characteristics of the analog-digital system for the incomplete scale input signal. The method of measuring the ADC static errors for an input sinusoidal incomplete scale signal, which is a histogram measurement method modification for a signal exceeding the full scale, has been developed. In the standard histogram method the overlapping of the range of input voltages, corresponding to the full scale, is necessary to ensure the fall out of all possible codes at the ADC output in presence of errors in amplification and zero bias. The magnitude of the offset in the standard method has been determined by the number of the samples that are overhead working range of ADC. In the proposed method a conditional overlap of the range, which permits to determine the static errors of the analog-to-digital conversion, has been used. The calculation of static errors in the ADC conversion has been reduced to calculating the amplitude of the output signal according to the histogram of the advantageous ADC codes. The transition levels have been calculated and the offset and gain errors have been determined. The proposed method has been tested by modeling in the MATLAB package. The accuracy of the method is consistent with the expected values of the input errors. The proposed method allows calculating the errors of conversion of analog to digital systems, in which there are blocks that limiting the ADC input signal.
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