本論文以一脊髓電刺激系統設計所需之兩個週邊電路為研究主題：16通道高壓電刺激產生器，以及脈衝頻率調變升壓轉換器。

第一個研究主題為一16通道高壓電刺激產生器，係針對植入式脊椎電刺激系統，並搭配由五個電壓倍壓器疊接組成之電荷幫浦電路，將系統電壓升壓至高於10伏特，以符合脊髓電刺激系統之需求。而此16通道高壓電刺激產生器共採用16組電刺激波形產生器，以驅動相對應之16組電極，每一組電刺激波形產生器係由一高壓運算放大器與高壓類比開關組成。和現有之技術與市售產品相比，本設計能夠以更低之成本與更好的靈活性來達到脊髓電刺激系統之規格。整體電路以TSMC 0.25 µm CMOS high voltage mixed-signal based BCD 1P5M salicide 2.5/5/60 V製程實現，並以實際晶片量測驗證本設計之正確性。

第二個研究主題為一脈衝頻率調變升壓轉換器，其採用限電流機制與最小關閉時間單擊電路，以控制脈衝頻率調變之運作。此升壓轉換器電路係操作於非連續導通模式，並且利用脈衝頻率調變模式之控制，能夠達到更高的轉換效率、更小的輸出電壓漣波、與更好的調節率。整體電路同樣以TSMC 0.25 µm CMOS high voltage mixed-signal based BCD 1P5M salicide 2.5/5/60 V製程進行設計與模擬，量測結果顯示此升壓轉換器電路之輸入電壓範圍為2.5 ~ 4.2伏特，輸出電壓可穩定於12.1伏特。輸出電壓漣波約為130毫伏特，轉換效率為85 %。

This thesis consists of two topics, i.e., a 16-channel high-voltage stimulation generator and a pulse frequency modulation (PFM) boost converter, which are mainly designed for spinal cord stimulation (SCS) system applications.

The first topic presents a 16-channel high-voltage stimulation generator to enlarge the stimulation signal swing on high-impedance electrodes of the SCS systems. Particularly, a charge pump composed of 5 cascaded voltage doublers is used to boost the core voltage (2.5 V) to higher than 10 V for the SCS system requirement. A total of 16 stimulation waveform generators are included to drive 16 corresponding sets of electrodes, where each generator is composed of high-voltage operational amplifier and high-voltage analog switch. Compared with existing reports and commercial products, the proposed 16-channel high-voltage stimulation generator attains better flexibility and lower cost to meet the SCS system specifications. This design is realized using TSMC 0.25 µm CMOS high voltage mixed-signal based BCD 1P5M salicide 2.5/5/60 V technology.

The second topic discloses a pulse frequency modulation (PFM) boost converter, particularly controlled by a current-limiting design and a minimum off time one-shot circuit. The boost converter is operated in a discontinuous conduction mode. The converter controlled by this PFM approach has higher efficiency, smaller output ripple, and better regulation. The converter is designed and simulated using TSMC 0.25 µm CMOS high voltage mixed-signal based BCD 1P5M salicide 2.5/5/60 V technology. Measurement results show that the converter can accommodate with an input voltage from 2.5 V to 4.2 V, and the boosted voltage is up to around 12.1 V. The output ripple is about 130 mV, and the efficiency is as high as 85%.

摘要 i
Abstract ii
圖次 v
表次 viii
第一章 概論 1
1.1 研究動機 1
1.2 相關文獻與研究討論 3
1.2.1 脊髓電刺激系統 3
1.2.2 植入式電刺激產生器 6
1.2.3 脈衝頻率調變升壓轉換器 8
1.3 論文大綱 10
第二章 16通道高壓電刺激產生器 11
2.1 簡介 11
2.2 16通道高壓電刺激產生器 12
2.3 16通道高壓電刺激產生器電路設計 14
2.3.1 電荷幫浦電路 14
2.3.2 電流式數位類比轉換器 17
2.3.3 16通道取樣電路 18
2.3.4 電刺激波形產生器 19
2.3.5 高壓運算放大器 21
2.3.6 高壓類比開關電路 22
2.4 電路模擬與預計規格 24
2.4.1 電路佈局後之模擬結果 24
2.4.2 電路佈局 29
2.4.3 預計規格 31
2.5 晶片實作與測量結果 32
2.5.1 晶片照相圖 32
2.5.2 晶片量測結果 33
2.5.3 效能比較 38
2.6 結果與討論 39
第三章 脈衝頻率調變升壓轉換器 40
3.1 簡介 40
3.2 脈衝頻率調變升壓轉換器 41
3.3 脈衝頻率調變升壓轉換器電路設計 44
3.3.1 高壓功率N型電晶體開關 44
3.3.2 閘極驅動電路 44
3.3.3 單擊電路 45
3.3.4 比較器電路 47
3.4 電路模擬與預計規格 48
3.4.1 電路佈局後之模擬結果 48
3.4.2 電路佈局 52
3.4.3 預計規格 53
3.5 晶片實作與測量結果 54
3.5.1 晶片照相圖 54
3.5.2 晶片量測結果 55
3.5.3 效能比較 61
3.6 結果與討論 63
第四章 結論與未來工作 65
參考文獻 68

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