An external control unit implemented for stimulator ASIC testing

This paper presents the design and development of an external control unit (ECU) for a stimulator ASIC testing purposes. The ECU consists of a graphical user interface (GUI) from the PC, a data transceiver and a power transmitter. The GUI was developed using MATLAB for stimulation data setup. The data transceiver was designed using hardware description language (HDL) Verilog code and was implemented in a Virtex-II Pro FPGA board. The overall stimulator ASIC design architecture and its operation for an epiretinal implant application are briefly explained to correlate with the ECU’s design requirements. The flexible multichannel stimulator ASIC was successfully fabricated in a 0.35μm AMS HVCMOS technology. Conducted simulation and measurement results on stimulation waveform generation, supply voltage compliance and external control of supply voltage adaptation validate the functionality of the designed ECU and the stimulator ASIC.Keywords: external control unit; data transceiver; stimulator ASIC; retinal prosthesis; epiretinal implant; stimulation waveform; Manchester data; voltage compliance

An experimental study on passive charge balancing

This paper presents a simplified analysis of the electrode potential upon mismatched, biphasic stimulation using passive discharge techniques, e.g. by shortening of the electrodes. It turns out that especially for microelectrodes the required shorting intervals become as large as to limit a feasible stimulation interval. If no blocking capacitors can be used due to limited space and the degree of miniaturisation, the passive discharge even imposes severe risks to the surrounding tissue and the electrode

Exploring the therapeutic effects of micro-pulse stimulation

Electrotherapy is not so commonly used in veterinary practice as in human. Microstimulator is a new electrotherapeutic device designed especially for the horses’ patients. Its unusual configuration of pulse parameters makes this method appropriate for the swelling treatment and tissue regeneration after the minor injuries. Nine horses with swelling of the limb caused by minor injury such as tendinitis, sprains etc. were included in the study. Micro-pulse stimulation was applied once a day until the total regress of problems. The course of the experiment was documented in photographs and video recordings that were significant for evaluation of the effectiveness of micro-pulse stimulation in this application. Based on the results, it seems the micro-pulse stimulation really has positive effect on swelling reduction, and so the overall tissue regeneration, consisting probably in analgesic and anti-inflammatory effects. © Springer International Publishing AG 2018.Brno University of Technology; European Regional Development Fund under the project CEBIA-Tech Instrumentation [CZ.1.05/2.1.00/19.0376