神经传导束中断是脊髓损伤后功能障碍的主要原因。微电子神经桥是利用微电子芯片或模块旁路受损神经传导束,重建因神经通路中断而丧失的功能。设计了一种基于0.5um CMOS工艺的低功耗、全集成微电子神经桥电路,版图面积为1.21mm×1.18mm。详细介绍了微电子神经桥核心单元电路低功耗两级运算放大器和输入/输出轨至轨运算放大器的设计。仿真结果表明,微电子神经桥接系统的通频带完全覆盖神经信号的频谱范围,增益可调至足够大,适用于神经信号探测和功能电激励。系统在±2.5V供电情况下,功耗仅为3.4mw,低功耗和系统全集成使得微电子神经桥向最终实现体内植入迈进了一步。
The interrupt of nerve tracts is the main reason of dysfunction after spinal cord injury. Microelectronic neural bridges bypass damaged nerve tracts with microelectronic chip or module and rebuild the lost neural function. This fully integrated low-power microelectronic neural bridge circuit was designed with a 0.5 um CMOS process, the area of 1.21 mm × 1. 18 mm. As core elements, the twostage operational amplifier and the input/output rail-to-rail operational amplifier were described. Simulated results show that the working band of the system completely covers the spectral range of nerve signals and the gain can be adjusted to be large enough for neural signal detection and functional electrical stimulation. The power consumption of the system is only 3.4 mW with ±2.5 V power supplies. The peculiarities of low power and fully integreated in a chip make a forward step for the microelectronic neural bridge to the ultimate implantable realization.