Modeling Inductive Coupling for Wireless Power Transfer to Integrated Circuits

With the trend of portable electronics to go battery-less, Inductive Coupling Wireless Power Transfer (ICW Power Transfer) is becoming commonplace. Inductive Coupling has shown to be a good technique for proximity and wireless power transfer in general, because it permits the easy use of impedance matching and resonance circuits. An important potential application is powering Integrated Circuits (ICs) from a PCB (Printed Circuit Board) without using conductive pins. While using ferromagnetic core materials improves coupling, conductive non-ferromagnetic ones like most IC's substrates, decrease coupling and ICW Power Transfer performance. In this paper we developed a simple theoretical model for ICW power transfer and compared it with 3D Electromagnetic simulations of an inductive link system to ICs. The results show that enough power can be supplied to very low power consumption ICs. As this technique can be also used to perform wireless communications, it opens the possibility to design ICs without pins at all.