神经信号再生专用微电子系统的设计

Design of special microelectronic system chip for neural signal regeneration

根据神经束电信号的特点,提出一种适用于中枢神经束电信号探测放大和再激励的微电子系统设计方案,功能单元包括微弱神经电信号探测电路、交流信号耦合电路和神经束再激励电路.为面向生物体植入应用,系统设计主要考虑功耗、噪声和交流耦合输入等性能.另外,设计了2种运算放大器单元,分别是用于前置电路的低噪声、低功耗两级运算放大器和具有高增益、高驱动能力的输入输出全摆幅恒跨导折叠运算放大器.系统采用CSMC双层多晶硅双层金属(DP-DM)标准0.5μm CMOS工艺设计完成.仿真和测试结果表明设计芯片实现了微弱低频电信号放大功能,可用于神经信号再生应用,功耗和体积满足生物体植入式器件的要求.

According to the features of neural signals,a microelectronic system is designed for central nervous signal detection and stimulation,and realized in CSMC＇s 0.5μm CMOS（complementary metal-oxide-semiconductor transistor） technology.The main modules of the system include the weak neural signal detection circuit,the ac-coupled circuit,and the stimulating circuit.The requirments of the implantation use,the performance of power dissipation,the noise performance and the ac-coupled input are discussed in detail.Two operation amplifiers（OPAs） are used in the system.One is low-power low-noise two-stage OPA used for front-end circuit performance,and the other is constant-gm RTR（rail to rail） input and output OPA used for obtaining high gain and high driver.The results of simulation and test show that the system has the function of weak low-frequency singal detection and the potential of application in neural signal regeneration and body implantation.