Safety Module for a High Frequency Arbitrary Waveform Generator

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The goal of the REValUE Project is to design a test device which is able to stimulate nerve tissue with current driven, high frequency stimulation in the range from 1 to 15 kHz and 1 to 10 mA. The test device will be used in research to pudendal nerve blockage. This thesis describes the design process of a safety module for this device. The safety module should guarantee that every stimulation with the device is within the safe stimulation parameters, it should stop any stimulation signal that exceeds 15 mA, 10.5 V or 30 μC/cm . In this thesis a design is proposed that can detect over stimulation. In case of over stimulation, further stimulation is stopped and the stimulated tissue is discharged. Additionally, the module discharges the tissue when the device is shut off.The prototype built during this project is able to stop signals that exceeds 26.7 μC/cm , 15.5 mA and 11 V. Design adjustments to improve the performance of the device are proposed in the discussion section, after which the module will be able to prevent exceeding the safety parameters. The requirement for DC blockage turned out to be an issue in the proposed design. An alternative topology has been thought of, but because of time limits the new design could not be tested. After the improvements proposed in chapter 10, the system should meet all the requirements and guarantee safe stimulation.