用于外周神经的干涉电流刺激器设计

设计了一种用于外周神经电刺激的干涉电流刺激器。该刺激器为两路电流输出，可以产生4种波形，每种波形的频率、幅度等参数可在上位机进行设置，频率分辨率为0.2 Hz，幅度分辨率为0.01 mA，时间分辨率为0.1 μs。该刺激器的特点在于可在刺激强度一定的条件下连续改变电流比，或在电流比一定的情况下连续改变刺激强度。上位机采用LabVIEW开发，下位机采用FPGA对3片DAC进行控制，DAC产生的波形信号经过隔离恒流源电路后施加到负载。经过测试，刺激器能够准确产生4种波形，电流偏差在2.6%以内，恒流效果良好。该刺激器体积小，操作简单，产生波形稳定，可以用于无损选择电刺激研究。

Design of interference current stimulator for peripheral nerve

Abstract: An interference current stimulator for peripheral nerve electrical stimulation is designed. The stimulator which is a two-way current output can generate 4 kinds of waveforms. The frequency, amplitude and other parameters of each waveform can be set in the upper computer. The frequency resolution, amplitude resolution and time resolution are 0.2 Hz, 0.01 mA and 0.1 μs, respectively. The stimulator is characterized in that the current ratio can be continuously changed under the condition that the stimulation intensity is constant, or that the stimulation intensity can be continuously changed when the current ratio is constant. The upper computer is developed by LabVIEW and the lower computer uses FPGA to control 3 DAC. The waveform signal generated by the DAC is applied to the load after being isolated by the constant current source circuit. After testing, the stimulator can accurately generate 4 kinds of waveforms, with a current deviation within 2.6% and good constant current characteristics. The stimulator which is small in size, simple in operation and stable in waveform generation can be used for the non-destructive electrical stimulation studies.