本論文提出一個應用於電刺激系統之含有電容共用殘餘電荷偵測電路同時達到主動電荷平衡之電荷模式刺激器，主要應用於癲癇抑制，使發作之時可以即時的做症狀減緩的效果。在電路實作及系統應用層面同時考量之下，希望降低電路設計複雜度，並且考慮到電晶體耐壓以及未來系統整合的製程問題，因而採用電荷模式刺激為研究方向。本論文電路特點為擁有殘餘電荷偵測器合併於電刺激器當中，讓使用者可以得知實際刺激到電極阻抗上的電荷量，進而可以針對刺激參數進行最佳化的調整，同時加入主動電荷平衡技術使電荷刺激器在不同的阻抗大小情況之下都可以由電路內部主動地去達成陰極以及陽極電荷的補償，避免電荷累積在電極阻抗上造成電極溶解以及周圍組織受損的風險。由於刺激電路以及殘餘電荷偵測器的共通點為都需要電容且進行充放電荷的動作，因此決定使用電容及相位共用技巧將電路進行合併來達成同時可以進行殘餘電荷檢測的電荷刺激器，藉此使電路可以更為精簡且整合。
本論文之晶片實現使用了TSMC 0.18 μm 1P6M的製程，刺激時序以及參數使用FPGA進行數位控制，從量測的結果可以驗證刺激動作以及時序上的正確性，並且波型為指數型衰減的刺激波型，相較於矩形刺激波型擁有較好的功率效率。刺激器量測參數使用1μF大小的刺激電容，陰極刺激脈波寬設定為 2000 μs ，刺激的頻率為100 Hz的情況下，對電極阻抗RC串聯模型為 1kΩ+1μF 進行刺激驗證，在此條件之下，陰陽極的電荷誤差量為0.38 %，而動態功率消耗的部分為1.2204 mW。整體刺激參數為可程式化的調整，針對刺激電容的刺激總量上限之調變、陰極刺激的脈波寬度調變以及刺激頻率之調變，皆可於量測結果中顯示其功能性。同時此電路晶片也於實務應用上進行體內動物實驗 ( in-vivo ) 的驗證，從實驗結果顯示出電路晶片對於癲癇抑制的效果，也證明了本論文所提出的電路於系統應用上之有效性。此外，將實驗結果與先前電流模式刺激器進行比較，觀察出電流刺激在刺激抑制期間會有比較大的artifact且需要一段穩定時間才能由腦波進行抑制效果的觀察，相比之下電荷刺激的artifact較為輕微並且將刺激區間進行放大可以直接觀察刺激區間的腦波變化，於EEG進行腦波觀察的過程與電流刺激器相比是相對有優勢存在的。

This paper proposes a charge-mode stimulator for use in an electrical stimulation system, which utilizes a capacitor-reused technique in residual charge detector and achieve active charge balancing simultaneously. The design is mainly used for epilepsy suppression systems, with the aim of achieving real-time symptom relief during seizures. Taking into account the complexity of the circuit design, the high voltage tolerant of transistors, and system integration requirements in the future, a charge-mode stimulator is adopted. The residual charge detector allows users to understand the current stimulus situation, enabling them to make optimal adjustments to the stimulation parameters. Based on the information of the actual stimulation charge, the active charge balancing can effectively prevent the accumulation of mismatched charges on the electrode impedance. Considering the commonality of the use of capacitor and charging/discharging phase in stimulation circuit and charge detector, capacitor-reused and phase-reused techniques contribute to achieving greater integration of the overall stimulator circuit. The proposed charge mode stimulator has been implemented in a 0.18 μm 1P6M CMOS process with core area of 0.2127 mm2. The measurement results demonstrate the accuracy of the stimulation functionality, and the programmable stimulus parameters. The effectiveness of the proposed charge mode stimulation for the epileptic seizure suppression has also been verified through animal experiments.

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