This invention introduces new control, circuit and system design techniques to provide two levels of power and voltage regulations: local voltage regulation and wireless power regulation
Implantable Medical Devices require a power source to perform actions such as functional stimulation (cochlear and retinal implants), electro-stimulation (pacemakers, defibrillators, neurostiumulators), drug delivery (pumps and infusers) and biosensors (health/disease monitoring and drug efficacy measurement, etc.).
Traditional power is provided by batteries. Implanted batteries have limitations on physical size, energy density, biocompatibility and possible chemical side effects, reliability and longevity. Use of an external battery requires leads that penetrate the skin, which can be a source of infection and discomfort. Wireless methods have also been developed and have the added advantage that they can be used as a means of communication as well as power transfer.
This invention introduces new control, circuit and system design techniques to provide two levels of power and voltage regulations: local voltage regulation and wireless power regulation. With this novel wireless hysteretic control, the design is the first fully integrated wireless power transfer (WPT) system that eliminates the need for any off-chip components, wires or sensing coils, which were required in previous works, to achieve both receiver (RX) local voltage and transmitter (TX) wireless power regulations, with enhanced light-load efficiency, instant transient response and intrinsically stable operation. Up to 20% efficiency enhancement is measured compared to state-of-the-art.