Electronics for a safe direct current stimulator

Commercially available neuroprostheses, while successful and effective, are limited in their functionality by their reliance on pulsatile stimulation. Direct current (DC) has been shown to have great potential for the purposes of neuromodulation; however, direct current cannot be applied directly to neurons due to the charge injection thresholds of electrodes. We are developing a Safe Direct Current Stimulator (SDCS) that applies ionic direct current (iDC) without inducing toxic electrochemical reactions. The current design of the SDCS uses a series of eight valves in conjunction with four electrodes to rectify ionic current in microfluidic channels. This paper outlines the design, implementation, and testing of the electronics of the SDCS. These electronics will ultimately be interfaced with a separate microfluidic circuit in the device prototype. Testing the outputs of the electronics confirmed adherence to its design requirements. The completion of the SDCS electronics enables the further development of iDC as a mechanism for neuromodulation.