近年來隨著CMOS製程技術發展純熟，使積體電路可以應用在生物醫學領域，如植入式腦機介面應用於治療帕金森氏症。閉迴路深層腦部刺激系統會在偵測到異常神經活動進而給予適當電刺激抑制大腦不正常的放電，其中一項機制即是偵測多巴胺濃度變化。
欲偵測特定神經傳導物質需進行電化學檢測方式，本論文旨在設計出一個可以產生出電化學檢測所需的波形，並紀錄電化學反應所產生的電流值的電路，以精確分析出待測神經傳導物質的濃度。
本論文除了使用循環伏安法進行電化學實驗，亦將其和快速循環伏安法改良為脈衝伏安法。使用不同的掃描速率量測不同濃度的多巴胺溶液，峰值電流與多巴胺濃度呈高度正相關。
晶片設計將電流感測和波形產生器兩個功能整合並已完成下線，電流感測能夠紀錄電化學實驗所產生±10μA的雙向電流，其解析度可達到nA等級。波形產生器可以產生循環伏安法、快速循環法和脈衝伏安法的三角波和梯形波，掃描速率透過六位元電流數位類比轉換器調整範圍為20~1250V/s。

In recent years, with the development of CMOS process technology, a number of integrated circuits have been used in biomedical applications such as implantable brain-machine interfaces for treating Parkinson’s disease. Closed-loop deep brain stimulation system detects abnormal neural activities and provides appropriate electrical stimulation to suppress abnormal discharge in the brain, one of the detection mechanisms is change of dopamine concentration.
It needs to perform electrochemical test for detecting specific neurotransmitter. This thesis aims to design a circuit which can generate waveform for electrochemical test and record current of electrochemical reaction to precisely analyze neurotransmitter concentration.
Apart from cyclic voltammetry, this thesis modifies it and fast scan cyclic voltammetry as pulsed voltammetry to conduct electrochemical experiment. Measure different concentration of dopamine solution with different scan rate, there is a highly positive correlation between peak current and concentration.
Chip design integrates current sensing and waveform generator has been taped out. Current sensing mode can record ±10μA biphasic current from electrochemical experiment with resolution of nano-ampere order. Waveform generator can generate triangular and trapezoid waveform for cyclic voltammetry, fast scan voltammetry and pulsed voltammetry, with adjustable range of scan rate from 20 to 1250V/s by 6-bit current digital to analog converter.

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