A nano-power power management IC for piezoelectric energy harvesting applications

This paper describes a power management IC for piezoelectric energy harvesting which integrates an active AC-DC converter with residual charge inversion together with a smart self-supply architecture to speed up the start-up phase and increase harvesting effectiveness. Due to randomness of available power and to its typical intrinsic limitation to tens of μW the IC has been carefully designed to reduce quiescent current down to 150 nA while the efficiency is estimated to be at least 81%. Moreover this allows the system to be fully autonomous even with very low input energy. The IC has been designed in a 0.32 μm BCD technology from STMicroelectrics and its area is 4.6 mm².