Simple Constant-Current Neural Stimulator With Accurate Pulse- Amplitude Control.

摘要

A simple constant-current electrocutaneous stimulator for high-impedance loads using low-cost, standard high-voltage components is presented. A voltage-regulator powers an oscillator built across the primary of a transformer whose secondary delivers, after rectification, the high-voltage supply to switched current-mirrors in the driving stage. Since the compliance high-voltage is proportional to the stimulation current, overall power consumption is minimized. By adjusting the regulated voltage, control of the pulsed-current amplitude is achieved. A prototype with readily available components features stimulation currents of amplitude and pulsewidth. Pulse-repetition spans from 1 Hz to 10 Hz. Worst-case ripple is 3.7% I(skin)=1 mA. Measured pulse fall-time is shorter than 32 microns. Overall consumption is 4.4W I(skin)=20 mA. Subject isolation from power line is 4KV.