近幾年來，生醫電子已經越來越受到人們的注意以及重視，其中許多研究報告顯示，功能性電刺激可以用來治療許多已知的神經性疾病，或修補因神經損傷而造成的殘疾，恢復部分器官功能，進而改善病人的生活品質。神經刺激電路為功能性電刺激不可或缺的部分，掌管控制刺激訊號，其在設計上常面臨到兩個主要挑戰，一為需要較高的供應電壓，以輸出足夠大的刺激電流；另一為需保持刺激後的殘餘電荷夠小，以避免造成對電極的損害。高供應電壓的問題可藉由使用高壓製程或厚氧化層製程來解決，但前者成本高，後者面積大。
本論文使用一電壓限制技巧，限制每個元件所看到的電壓皆在其能承受的範圍以避免崩壞，並使用TSMC 0.18μm CMOS製程，製做可在12V供應電壓下操作的神經刺激電路，並附加一電流校正電路以減小殘餘電荷量至安全範圍內。在量測中，已成功輸出振幅為500μA的Bi-Phasic波形，並將陰極電流與陽極電流的差距縮小至0.57μA內，DAC的INL最大為1.468LSB，DNL最大為0.393LSB，其輸出電流振幅、輸出頻率與輸出脈衝寬度皆可調整。本電路經過連續三天操作，其功能依然保持正常。

Bio-medical implantable devices have drawn more and more attention in recent years. Functional electrical stimulation (FES) has high potential to partially repair or at least improve the physiological function of patients suffering from neuron damage. Stimulators for this purpose usually face two design challenges of the required high supply voltage for compliance voltage, and the residual charge which eventually causes electrode corrosion. Using a voltage limit technique, a stimulator which can withstand 12V supply voltage is proposed in this study. A current calibration mechanism is added to limit the amount of residual charge within a safe range. The simulator has been fabricated using TSMC 0.18μm technology. Experimental results show that stimulation current up to 500μA could be delivered, and the current mismatch is less than 0.57μA. The stimulator successfully generated a 60 Hz biphasic stimulation waveform, whose amplitude and pulse width was tunable.

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