A Power-Adaptable Entropy-Coding A/D Converter

We report on a redesigned entropy-coding analog/digital converter (ADC) that combines analog/digital conversion and entropy-coding for integrated data compression and low-power operation. The new version has an increased flexibility of operation in terms of adaptable resolution, conversion rate and input signal statistics. This feature allows to adaptively react to changes of the situation and to put the converter in each case into the optimum configuration. A comprehensive power model of the converter is presented that reflects precisely the power consumption determined from experiments. The model is very useful for optimizing the converter configuration in the node of a wireless sensor network for specific situations. A possible application is demonstrated.