A 400 MHz Voltage-Mode-Based Fully Integrated Regulating Rectifier for Deep Tissue Bio-implants

In this paper, a voltage-mode-based fully integrated resonance regulating rectifier (IR
³
) running at 400 MHz has been designed for wireless power transfer (WPT) implants in deep tissue. Separate on-&-off delay compensation circuits are designed to avoid reverse current for efficiency and lower ripple factor, which is about 0.28% at 1.8 V regulated output voltage. With the regulation compensation circuit and the delay compensation scheme, this rectifier can reach a voltage conversion efficiency (VCE) of 1.73 to overcome the low coupling coefficient due to the deep implant, and the whole system achieves a power conversion efficiency (PCE) of 67.8% with 2 mW load.