Does a coupling capacitor enhance the charge balance during neural stimulation? An empirical study

Does a coupling capacitor enhance the charge balance during neural stimulation? An empirical study

Van Dongen, M.N.
Serdijn, W.A.

Electrical Engineering, Mathematics and Computer Science

Microelectronics

2015-05-29

Due to their DC-blocking characteristic, coupling capacitors are widely used to prevent potentially harmful charge buildup at the electrode–tissue interface. Although the capacitors can be an effective safety measure, it often seems overlooked that coupling capacitors actually introduce an offset voltage over the electrode–tissue interface as well. This work investigates this offset voltage both analytically and experimentally. The calculations as well as the experiments using bipolar-driven platinum electrodes in a saline solution confirm that coupling capacitors introduce an offset, while they barely contribute to the passive charge balancing. In particular cases, this offset is shown to reach potentially dangerous voltage levels that could induce irreversible electrochemical reactions. This work therefore suggests that when the use of coupling capacitors is required, the offset voltage should be analyzed for all operating conditions to ensure it remains within safe boundaries.

electric stimulation
implantable neurostimulators
electrodes

http://resolver.tudelft.nl/uuid:e06337b0-b68e-471c-82cf-0f45c7bc0234

Springer

0140-0118

https://doi.org/10.1007/s11517-015-1312-9

Medical & Biological Engineering & Computing, 2015

Institutional Repository

journal article

(c) 2015 The Author(s)
This article is published with open access at Springerlink.com