Keynote speech: Data converters for mobile and autonomous applications

Abstract

There is an increasing interest in mobile or autonomous applications, which are for systems that do not need and do not have the possibility of refueling power. The used power must come from the environment by harvesting what is available and transforming it into electrical form. Those systems move around, i.e. they are they nomadic and often are connected object and we call this category IoT. Since available power is very low its consumption becomes a key design parameter. Moreover, transducers transforming the harvested energy into electricity often give rise to very low voltage. The result is that the analog circuits of nomadic applications must work with sub 1-V supply voltages and power consumption in the tens of hundreds of nW range. Digital circuits are power efficient and for very low power circuits they ensure a better sensitivity to supply noise than analog counterparts. Therefore, for modem nomadic systems moving quickly to digital is an essential strategy. Ensuring ultra-low power atmedium-high resolution (9–12 bit) forrelatively low signal bandwidth (100 kHz–1 MHz) is a typical request. SAR converters and sigma-delta modulators are used. Techniques and recent circuit implementations capable of satisfying diverse ranges of specificationsfor mobile and autonomous systems are presented.