On-Chip Configurable RF Energy Harvester for Biomedical Implantable Devices
S. Nagaveni, Praveen Hunasigidad, Deepali Pathak, Ashudeb Dutta
Abstract
This paper introduces an on-chip hybrid rectifier tailored for RF energy harvesting at 2.4 GHz. Leveraging advancements in CMOS technology, this solution offers a novel approach to powering devices, particularly suitable for implantable biomedical devices and applications. This proposed architecture features 3-stage reconfigurable hybrid rectifiers, with each stage comprising a regular threshold voltage (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{th}$ </tex-math></inline-formula>) MOS rectifier for high input power and a low (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{th}$ </tex-math></inline-formula>) MOS rectifier for low input power. The cross-coupled connection of both rectifiers ensures minimal ON-resistance and low reverse leakage current during forward and reverse biased conditions, respectively. Through effective reconfiguration of power paths, the proposed system achieves high power conversion efficiency across a broad input power range. This proposed system is designed and Implemented in UMC <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.18~\mu $ </tex-math></inline-formula> m CMOS technology with a Wi-Fi frequency of (2.4 GHz), the measured results are demonstrating an efficiency exceeding >35% for input power levels ranging from −23 dBm to −12 dBm, driving a load of 40 K<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula>.