A single-input dual-output 13.56 MHz CMOS AC-DC converter with comparator-driven rectifiers for implantable devices

A highly efficient single-input, dual-output AC-DC converter for wireless power transfer in implantable devices is implemented using the 0.18-μm CMOS process. The proposed AC-DC converter, consisting of three rectifiers with cross-coupled NMOS transistors and comparator-driven PMOS transistors, achieves up to 79.5% power conversion efficiency at 13.56 MHz operation frequency in order to provide dual outputs of 1.2 V and 2.2 V DC voltages along with 6.2 mA and 22.6 mA of current, respectively, to the implant device from a single RF input. The designed IC consumes a core die area of 0.18 mm².