植入式医疗装置的无线通信和能量收集电路

A Wireless Communication and Energy Harvesting Circuit for Implantable Medical Devices

针对传统植入式医疗装置中无线通信电路功耗高、面积大、通信距离短且通常不具备能量收集功能的问题,提出了一种高效率的无线通信和能量收集电路。无线通信电路通过采用脉冲幅度调制的近场通信方式,与传统的开关调制方式相比,其功耗更低,并且在相同误码率的情况下能够实现更远的通信距离;能量收集电路通过使用低功耗的MOS整流和稳压电路,其具有高转换效率、小面积的优势。采用0.35μm CMOS工艺,完成了电路的设计和仿真,通过搭建实验平台,对所提无线通信系统进行了验证。实验结果表明:所提电路可在2.0~2.8V电源下工作,在误码率不超过10-5的情况下,最远无线通信距离可达12cm,并且工作时的电流低于26μA;无线能量收集电路在输入800mV、128kHz正弦信号时,输出直流电压为1.73V,能量转换效率达到20%。所设计电路可应用于起搏器等植入式医疗装置中,可实现高效率的无线通信和能量收集。

A high-efficiency wireless communication circuit with energy harvesting function is presented to solve the problems in the wireless circuits in traditional implantable devices,such as high power consumption,large chip area,short communication distance and lack of ability to harvest energy.The proposed pulse amplitude modulation（PAM）based communication circuit consumes lower power and can reach a longer communication distance with the same bit error rate when compared with traditional on-off keying（OOK）modulation method.The energy harvesting circuit contains low-power voltage rectifier and regulator designed with MOS devices,which has the advantages of high efficiency and small chip area.The proposed circuit is designed and simulated using a 0.35μm CMOS technology.A test environment is also built to verify the proposed circuit.Simulation and measurement results show that the proposed circuit can operate under a power supply range of 2.0-2.8 V,and achieve a maximum communication distance of 12 cm with the working current lower than 26μA and bit error rate less than 10-5.With a 800 mV and 128 kHz input,the energy harvesting circuit outputs a 1.73 V DC voltage with 20% energy conversion efficiency.The proposed circuit is suitable for implantable medical devices such as cardiac pacemakers.