Human life expectancy has gradually increased in part through rapid advances in technology, including the development and use of wearable and implantable biomedical electronic devices and sensing monitors. A new architecture is proposed in this paper to replace the traditional diode circuit implementation in wireless power supply systems applied to the above-mentioned devices and monitors. By achieving near-ideal power transistor switching and leveraging the characteristics of conventional diodes to prevent reverse current, the proposed approach greatly improves the performance of the energy harvester in power conversion. The MOS harvester used in the uninterrupted permanent wireless near-field power supply described here for use in biomedical systems was designed and verified using the Taiwan Semiconductor Manufacturing Company (TSMC) standard 180-nm process, achieving performance results of Voltage conversion efficiency (VCE) = 73.55-95.12% and Power conversion efficiency (PCE) = 80.36-90.08% with the output load (0.1-1 kΩ) under 3.3 V ac input with an overall area of 1.189 mm2. These results are expected to create an important technical niche for new "green-energy" miniaturized energy sensing systems including cutting edge wirelessly powered biomedical electronics applications.
Keywords: AC-DC power converters; RFID tags; energy harvesting; implantable biomedical devices; integrated circuits; rectifying circuit; wireless sensing systems.