Application of Simulink for the Study of Dual-Slope ADC

Currently, the number of digital measuring transducers of various physical quantities is growing in measurement and control tasks. The functioning of digital converters presupposes the presence of analog-to-digital converters (ADC) in their structure. Among the ADC architectures used, the principle of dual-slope integration can be characterized by high noise immunity and relative ease of implementation. In the tasks of studying the characteristics of dual-slope ADCs and educational tasks, the use of real chips or their prototypes in a large number of cases turns out to be inconvenient. It´s especially related to the study of metrological characteristics, which, due to the smallness of their values against the background of random signal fluctuations, is extremely difficult to determine on a real prototype. This paper is devoted to the development of a dual-slope ADC model using the Simulink simulation package. The proposed model allows us to evaluate the static and dynamic characteristics of the dual-slope ADC. Most ADC parameters (sampling frequency, input signal range, reference signal value, duration of the first integration cycle) are configurable via a dialog box with the user. The issues of suppression of stationary and random external interference are considered. Recommendations are given for choosing the duration of the first integration cycle depending on the type of noise interference in the input signal. The obtained analytical expressions are confirmed by the results of simulation modeling of the developed model. The resulting model can be widely applied in the educational process, especially in the format of online education.