由已知的研究顯示，深腦電刺激可以抑制帕金森氏症患者的病情，但是腦內運作的機制仍然未知，故欲發展一個可以無線傳輸電源的微系統，來達到研究的目的。而為了使前端感測到的生醫訊號做更進一步的資料處理，需要透過類比數位轉換器，來將感測到的訊號轉換成數位碼，以利後端數位訊號處理操作。此微系統在無線傳輸的過程中，需要將二次測線圈的載波訊號轉換成內部晶片的直流電源，但以此無線傳能方式會造成較大的漣漪(Ripple)抖動，而造成類比數位轉換器效能低落。
考量到電源抖動造成類比數位轉換器效能低落的問題，本論文提出一個可以免除參考電壓的連續漸近式類比數位轉換器。透過內部自行產生參考電壓，不需外接抖動電源，可使類比數位轉換器保有原來設計的性能表現。同時利用錯誤容忍機制，可補償比較器上，因為製程變異而造成電荷變動偏移。使用0.18μm標準CMOS製程，量測結果顯示，此類比數位轉換器可以操作在免除參考電壓的情況下，在0.75V~1V仍然可以操作保持SNDR為46.7dB。而在1V的情況下，取樣頻率可以由167KHz到7.7MHz。在VDD上若有一個250mV振幅的抖動時，相較於傳統的類比數位轉換器SNDR大降至剩下29dB，此類比數位轉換器仍可保持SNDR有44.25dB。故由結果顯示，在電源有較大抖動情況下，利用免除參考電壓的方式，此類比數位轉換器仍可以保持穩定性能。

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