Study and Simulation of an Analogical-to-Digital Converter 8 Bits

Diouba sacko, Alpha Amadou Keita, Drissa Traore

According to the advantages of the digital signal processing, we turn us towards the numerical field.¶ The design of digital circuits in the majority of cases is much less complex than its analogical counterpart.¶ It is an incomparable flexibility and entrains a reduction of cost.¶ The digital signal is stable, robust and insensitive to noise.¶ It allows us to reach a very high degree of accuracy.¶   However, the sources of the electrical signals are mostly analogical;¶ consequently, these signals must be digitized for being treated numerically.¶ The analogical-to-digital converters (ADC) constitute the bridge between the two fields (analogical and digital).¶ The portable biomedical applications for instance have contributed to the development of more powerful analog-to-digital converters with a low consumption of energy compared to the speed of operation.¶ The industrial development of the integrated circuits during the last decade was so fast, that it is now possible to integrate a complex system on just one chip.¶ This evolution towards increasingly high levels of integration is justified by the needs for more powerful, light and compact systems with a minimum consuming power.¶

In this paper, we design and simulate an analogical-to-digital converter.¶ The digitalization of systems allows us less consumption of energy and higher precision. The principal architectures of analog-to-digital conversion are classified in two families:¶ ADC at Nyquist rate (Nyquist rate converter) for those converters, the sampling rate (F_S) coincides with the Nyquist rate of the ADC.¶

These converters can be under various architectures like ¶integrator, reallocation of burden-sharing, algorithmic, parallel Flash and pipeline. The ADC¶ with oversampling, are the Sigma-Delta and the Sigma-Delta pass-band. ¶