This paper examines the quantization error of a modulator for delta-sigma analog-to-digital converter (DSADC). In opposite to many papers, the analytical equations are found in time domain. This approach allows the authors to present the modulator as analog-to-digital converter (ADC) of input signal to code for given length of digital sequences at the modulator output. Such presentation is useful for investigation of quantization error for ordinary DSADC and can also be considered as the base for a new ADC type. Both analytical equations and results of simulations are used to find the sources of quantization errors: effect of the scale end, limited number of code transition levels, unequal length of code bin widths, non-ideal digital filters. Some suggestions are made to decrease influence of mentioned sources on quantization error including the new ADC type with conversion delay.

Analog-to-digital converters are commonly tested by applying a pure sine wave at their inputs. Since the exact parameters of the sine wave are very difficult to precisely obtain, an indirect method is used: the measured samples are used to determine the sine wave which best fits them. The ADC is characterized then by analysis of the differences between the samples and the sine wave. This is described in the IEEE standards 1241-2000 and 1057-1994.
The generally applied method for the fit is least squares (LS). If the error (the deviation of the ADC output samples from the true sine wave) is a random sequence, with independent, identically distributed zero-mean samples, the LS fit effectively averages it out. However, when the quantization errors dominate in the observations, this is not true. Strange, systematic errors may arise, which cannot be averaged out. The paper examines these errors, and makes suggestions how to reduce them.

Static testing and diagnostics of digital to analogue converters involve the measurement of the nonlinearity of the converter and the successive estimation of suitable error terms, namely linearity and intermodulation errors. At the state of art, the estimation of the aforementioned error terms is performed by means of two linear transformations, which are applied to the nonlinearity array characterizing the converter. The computational burden of this approach could be too heavy; moreover, practical relations for assessing the uncertainty affecting the results are not available.
An alternative approach for estimating linearity and intermodulation errors is studied and proposed in this paper. By exploiting some nice features of the bit error functions, very straightforward relations that facilitate the estimation of the error parameters and allow a direct evaluation of the uncertainty affecting the results are defined. A number of laboratory tests on an actual D/A converter are conducted in order to assess the reliability and efficiency of the proposed approach.

In this paper a new approach to the measurement and compensation of the soft components of the integral nonlinearity (INL) of the ADC in the time domain is presented, using both sine and triangular waves. Connection will be established between the user oriented nonlinear description based on memoryless nonlinear models using orthogonal polynomial series and the manufacturer oriented specification, the INL. Using the orthogonal series representation it will also be shown how the nonlinearity of the generator can be compensated a posteriori in the ADC characterization, allowing for a better assessment of the ADC. Finally, simulation results will be presented that portray the applicability of these methods and representations.

This paper presents a new method to measure the discrete probability density function (p.d.f.) of an ergodic random path avoiding the influence of differentioal non-linearity of applied ADC. This method is useful to measure the precise p.d.f. by using the successive approximation type ADC or the flash type ADC. The most important field to apply is the radiation pulse height analysis.