Behavioural Modelling of Sampled-Data Systems with HDL-A and ABSynth

In this paper we make use of a mixed analogue-digital HDL to model sampled-data systems. Modelling solutions are presented to code some sampled-data behaviour using either analogue or digital constructs of the language.<br>Two key operations – sampling and shifting – are presented first. Then, these facilities are used to code difference equations. This approach is validated on the example of a sampled-data filter. Finally, a ‘real-life’ switched-capacitor A to D converter is modelled and simulated. The results are compared with a transistor-level description.