近年來，因為CMOS技術發展以及製程工藝的純熟，讓積體電路可以應用在生物醫學上面;像是利用植入式腦積介面應用於治療帕金森氏症、癲癇等疾病的技術，越來越廣泛地受到關注與研究。
本論文旨在研究用於深腦電刺激療法帕金森氏症的植入式腦機介面晶片系統中的前端電路，這個前端電路也具備刺激假象消除的功能。刺激假象的產生是源自於在電極陣列中，鄰近的電極發出的刺激電流殘餘會造成紀錄電極上的電容產生振幅極大的電位差，這個振幅會遠超出紀錄放大器所能記錄的輸入訊號範圍進而導致放大器的飽和，因此在沒有消除刺激假象的情況下，刺激的同時並不能有效地記錄神經活動。本論文為了解決這個問題，設計出一個有刺激假象消除功能的前端電路。
本論文對於生醫放大器共設計與量測了兩個版本，由於第一版的雜訊以及推動能力等測量結果表現得不如預期，於是更換了架構設計出第二版的放大器，不只面積比起第一版要來得小，且測量也比第一版表現得好。在閉迴路的電路模擬當中，可以將振幅7mV的刺激假象降低至0.8mV，讓放大器能夠順利紀錄神經訊號。此論文將有助於閉迴路與自適性的刺激裝置於植入式腦機介面的應用。

In recent years, with the development of CMOS technology and the proficiency of process, a number of integrated circuits have been used in biomedical applications. For instance, implantable brain-machine interfaces for treating Parkinson’s disease, epilepsy, and other diseases have attracted more and more attentions and research resources.
This thesis aims to study the frontend circuit used in the brain-machine interface for studying the mechanism of deep brain simulation (DBS) and the therapy for Parkinson’s disease. Furthermore, the frontend circuit is able to cancel stimulation artifacts. The generation of stimulation artifacts is caused by the stimulation current delivered by adjacent electrode in the electrode array, which will cause the capacitance on the recording electrode to produce a large amplitude potential difference. The large voltage transients will exceed the input range of recording amplifier and saturate the amplifier. Therefore, without cancelling the stimulation artifacts, neural activities cannot be recorded during stimulation phase. To solve the problem, this thesis design a frontend circuit with stimulation cancellation.
Two versions of amplifiers are designed and tested. While the first version testing performances are below expectations. The architecture of the second version is changed. The area and testing performance of second version are better the first one. In closed-loop simulation, the stimulation artifact with 7mV amplitude can be reduced to 0.8mV, allowing the amplifier record neural signals. The study will be helpful for designing a closed-loop and adaptive stimulation device in the implanted brain machine interface.

致謝 i
摘要 ii
Abstract iii
目錄 iv
圖目錄 vi
表目錄 ix
第一章 緒論 1
1.1 背景介紹 1
1.2 腦機介面系統簡介 1
1.3 閉迴路系統介紹 2
1.4 研究動機 3
1.5 章節結構 3
第二章 文獻回顧 5
2.1 神經訊號特性及神經-電極介面模型 5
2.2 刺激假象介紹 7
2.3 刺激假象消除架構介紹 8
2.3.1 Chandrakumar團隊系統 9
2.3.2 Pazhouhandeh團隊系統 11
2.3.3 Samiei團隊系統 12
2.3.4 討論總結 14
第三章 第一版紀錄放大器設計與實現 16
3.1 預計規格 16
3.2 電路架構 17
3.3 模擬結果分析 23
3.4 量測結果分析 25
3.4.1 晶片量測平台 26
3.4.2 晶片量測結果 29
3.4.3 量測結果之總結 34
第四章 第二版記錄放大器設計與實現 36
4.1 電路架構 36
4.2 模擬結果分析 39
4.3 量測結果分析 42
4.3.1 晶片量測平台 42
4.3.2 晶片量測結果 44
4.3.3 量測結果之總結 48
第五章 具有刺激假象消除功能的前端電路設計 51
5.1 刺激假象模型 51
5.2 前端電路架構介紹 57
5.2.1 數位電路(adaptive filter) 58
5.2.2 比較器 60
5.2.3 數位類比轉換器 62
5.3 前端電路模擬結果 64
第六章 總結與未來展望 69
參考文獻 71

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