Research And Design Of Front End Circuit For Implanted Sensor Labels

Diabetes is one kind of worldwide complications and chronic diseases, and it is a serious threat to human health. Therefore, the diagnosis and treatment of diabetes are a major issue to biomedical Electronic Engineering. Treatment guidance is the detection of blood glucose, and there is an important significance to the continuous detection of blood glucose. Compared With conventional blood glucose measurement program, implantable glucose sensor system has many advantages that can reduce patient suffer, are easy to carry and may achieve real-time measurement and control. However, designing an implantable glucose sensor will face many challenges. A wireless implantable glucose sensor must solve the problems that wireless signal attenuates sharply in body and energy harvests, as well as other design difficulties such as sensor miniaturization, long life, high precision measurement signal and information security and so on.Research and design of glucose enzyme sensor at home and abroad has been much mature, but research of implantable glucose sensor is still in a preliminary stage. Based on radio frequency identification technology (RFID), wireless implantable the enzyme sensor signal processing system on chip(SoC) has become a research hotspot in recent years, the paper designs a front-end circuit system of enzyme sensor tag chip in accordance with ISO15693protocol.The main factors that affect the performance of the conventional electronic tag chip:energy transmission efficiency, low power system architecture and circuits. The enzyme sensor tag chip puts forward higher requirements for the former. The paper analyzes HF RFID tag energy transfer process, the factors that affect the energy transfer efficiency:antenna and the resonant capacitor impedance matching with the post-stage circuit, and energy conversion efficiency of the rectifier circuit. For the latter, the paper designs a enzyme sensor tag architecture. System works in low power consumption, and power consumption is about100uW. In the specific front-end circuits design, a rectifier circuit with high power conversion efficiency(PCE) is designed, and peak of PCE is about40%. Sensitivity of tag front-end is about-7dBm. Other sub-modules with low voltage, low power consumption and low noise are designed, and the total power consumption of front-end circuits is about27uA. After front-end circuits are simulated and analyzed, the chip is taped out in SMIC0.13μm RF process technology. The area of chip is about0.7mm2.