中文摘要：

微刺激器是一种通过对生物体内特定部位释放电流来达到一定刺激效果的医疗装置。其刺激效果与微刺激器所释放电流的参数有密切关系。为了能够在生物实验中寻找到刺激效果最佳的电流参数，论述了一种以FPGA为核心的微刺激器设计方案。这种微刺激器利用DDS技术，由FPGA芯片生成各种波形参数，其中频率、波形、幅值可控。结合数模转换电路和压控恒流源等外围电路，能够输出多种刺激电流，并且电流参数可调。介绍了这种微刺激器的原理和设计方案，并且进行了验证。应用这种微刺激器能够生成生物实验中所需要的双向脉冲波形。

英文摘要：

Micro-stimulator is a kind of medicine device, which can stimulate specific parts of organisms by generating amount of current. The stimulating effect is closely related with the current. In order to find the current parameters of the best results of stimulation, this paper introduces the design of micro-stimulator based on FPGA, which is based DDS technology. In this design, wave parameters are generated by FPGA chip. Among these parameters, frequency, wave form and amplitude can be modified. Cooperated with digital-to-analog conversion circuit and voltage-controlled constant current source, this system can generate a variety of stimulating current, which current parameters can be adjusted. In this paper, the principle and design of the micro-stimulator is described. The design of this microstimulator is also been verified. In bio-experiment, it could generate the needed biphasic pulse.