An omnidirectional wireless power receiving IC with 93.6% efficiency CMOS rectifier and Skipping Booster for implantable bio-microsystems

This paper proposes an omnidirectional wireless power receiving IC for implanted biomedical applications. The IC consists of new power receiving circuits (switch-mode CMOS Rectifier) and new power combination circuits (Skipping Booster). By predicting the coming of the current zero-cross-point (ZCP), the proposed CMOS rectifier switches current with more precise timing. By skipping the rectification in some certain periods, the proposed Skipping Booster combines energy from all rectifiers together. Thanks to the two new circuits, the wireless power receiving IC could receive omnidirectional wireless power with a peak efficiency of 93.6%, which is higher than the conventional results (30%~80%). It has been verified with a prototype of a batteryless endoscopic capsule.