Li-ion battery charger circuit for biomedical devices

In advance of biomedical devices, the demands of integrated power harvesting system for rechargeable battery applications are underlying issues. This paper presents a wireless power system for Li-Ion battery charger including voltage doubler (AC-DC), voltage linear regulator (LDO) and charging control loop applying multi charging phases method to minimize battery effect. Proposed Li-ion battery charger with input voltage is 6Vp-p at frequency 4MHz, DC output voltage is 4.1V and maximum DC output current is 1.5mA is designed using TSMC 130nm technology for implanted biomedical devices.