A Magnetoelectric Wireless Power Transfer System with a 97.25%-Efficient Load-Adaptive CMOS Rectifier for Miniaturized Implants

Fully implantable systems such as neural interfaces require wireless power delivery to eliminate bulky batteries and reduce the need for replacement surgeries. The growing functional complexity of implants, which now integrate sensing, stimulation, signal processing, and machine learning [1], continues to increase their power demands. These devices have diverse power needs, with high-power modes during training and low-power operation during inference, making flexible and efficient power delivery essential to support emerging applications. Yet, efficient power delivery to miniature implants remains challenging, particularly in the presence of misalignment, variable load conditions, and safety constraints.