Low frequency wireless powering of microsystems using piezoelectric-magnetostrictive laminate composites

Abstract

We have developed a new wireless powering technique for microsystems based on low frequency excitation of a piezoelectric-magnetostrictive laminate (i.e., magnetoelectric effect). The laminate composites subjected to a magnetic field have been used to generate an electric voltage (up to 285 V). Adequate power levels (10-80 /spl mu/W) for many microsystem applications have been generated by inserting a piezoelectric PZT sheet between two highly magnetostrictive Terfenol-D layers (strains of the order of 10/sup -3/ at 2-3 kGauss). The possibility of driving a microactuator with the generator has been demonstrated. Comparing with other remote powering techniques, this method possesses much higher voltage generation efficiency per generator volume.