Abstract : High performance inductively powered contactless systems, as under skin or cryptography systems, suffer from digital circuit high power consumption and low communication distances. The used of asynchronous logic has already proved benefits of this type of design: lower power consumption and high supply voltage variations robustness. The goal of this study is to take fully advantages of these properties developing a new class of inductively powered contactless systems dedicated to asynchronous operations. To reach this, those circuits are used in adequacy with event based communications through the inductive link.
This new class of fully asynchronous inductively powered systems is using event based communications, with dynamically variable data rates, and self-adaptive to data rate tags. Those communications through the inductive link are implemented using a phase modulation and an asynchronous cyclic code. The flexibility brought by this new communication scheme allows high data rate transmissions and a dynamically adaptation to environmental conditions. Thus, communication data rate can be reduced to improve communication distances or to reduce power consumption on tag. A prototype of this new tag class, implemented on a standard CMOS 0.13 um process, with 6 metal layers, has shown that any communication, up to 1.02 Mbps, is successfully demodulated with a global power consumption on tag below 120 uW