2019年新冠病毒的大流行改變了大家的生活型態，人們減少前往醫院以避免受到感染或是消耗貴重的醫療資源。因此，居家健康檢測與照護產品受到越來越多關注。
本文提出三個可用於居家檢測採用比較式頻率響應分析法的自動化電化學阻抗頻譜量測系統版本。這些系統包含一顆電化學阻抗頻譜訊號處理晶片、一些離散元件、一組資料擷取裝置以及一台筆電。其中第三版本的晶片是由三個主要功能區塊組成：一組可編程的寬頻弦波產生器、兩套可調式帶通濾波器以及一個阻抗數位轉換器。所使用的製程為台灣積體電路公司0.35μm 2P4M 3.3.V混合訊號製程，晶片面積為2.07×1.68 mm2。整套系統已透過離散電阻、電容以及實際人類血清白蛋白溶液進行測試與驗證。
此外，一些可以提升系統準確度以及優化系統複雜度的電路被提出。其中，整合斬波電路的全差分差動放大器可用來解決放大器的偏移電壓，而直流伺服迴路則可被用來消除系統不想要的低頻雜訊。另外，數位輸出的脈衝式類比除法器可以執行除法並提供數位輸出，可簡化後端訊號處理的流程。最後，一個十位元面積優化的循環路徑交換式逐次逼近時間數位轉換器被提出。與其他架構相比，其延遲元件的數量減少了至少50％。與前面提出的系統相比，可用來取代阻抗量測系統中的相位-數位轉換器。

The pandemic of the coronavirus disease 2019 (COVID-19) has changed our life, and people tend to avoid going to the hospital. Therefore, home-care biomedical electronic products have drawn more and more attention.
Three different generations of electrochemical impedance spectroscopy (EIS) measurement system based on comparative frequency response analysis method are proposed. These systems are composed of an EIS signal processing chip, some discrete circuits, a data acquisition module, and a laptop. The proposed 3rd-version EIS signal processing chip contains three main functional blocks: a wide-range programmable sinusoidal waveform synthesizer, two tunable bandpass filters, and an impedance-to-digital converter, and it was fabricated by using a 0.35μm 2P4M 3.3V mixed-signal polycide process. The die area of this chip is 2.07×1.68 mm2. The proposed EIS measurement system has been tested and verified by measuring resistance/capacitance circuits and real human serum albumin solutions.
Moreover, several circuits have been proposed to improve the accuracy of the system and/or optimize the complexity of the system. Among them, a fully differential difference amplifier with choppers is proposed to remove op offset, and a dc servo loop can be used to eliminate the undesired low-frequency signals. Besides, the concept of pulse-based divider with analog inputs and digital output is also proposed, and it has the functions of a divider and an analog-to-digital converter. At last, a 10-bit area-efficient cyclic path-swapping successive approximation time-to-digital converter (CPSSA-TDC) has also been proposed in this work. Compared to the other state-of-the-art TDCs, the proposed CPSSA-TDC reduces the number of delay cells by at least 50 %. Furthermore, it can be used to replace the phase-to-digital converter of the impedance measurement system.

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