近年來，隨著醫療科技的進步以及慢性疾病病患的人數增多，生物醫學檢驗技術越來越受到重視。因此，慢性病病患需要簡易且能夠及時進行自我檢測的醫學檢驗技術。現今，生物晶片成為電路設計領域的一項主流，它能夠將生物醫學檢驗技術整合進一個兼具輕薄短小的晶片裡，並僅需少量的檢體，即可同時檢驗多種的待測物。
電化學阻抗頻譜分析法(Electrochemical impedance spectroscopic, EIS)即是一項常用的電化學檢測方法。本論文所提出的阻抗數位轉換器即是用來整合一個能快速且自動化量測的電化學阻抗頻譜分析系統。與傳統的電化學阻抗頻譜系統不同的是，本電路未使用耗費面積的電路架構(例如：低通濾波器)，僅需簡單且小面積的電路架構就能實現。此外，本電路利用創新的電路架構實現了高解析度的數位轉換，並加入了特殊的設計以消除雜訊的影響。另外，本論文所提出的阻抗數位轉換器可適用於寬廣的輸入頻率。
此晶片使用台灣積體電路公司(TSMC) 0.35μm 2P4M 3.3V 混合訊號製程，以40 S/B封裝，尺寸為 。此阻抗數位轉換器耗功為0.831mW，輸入的訊號頻率範圍在10 Hz到10 kHz，最大可偵測的訊號振幅以及相位差分別是1.235V和+/- 177.4°

Biomedical detection techniques become more and more important recently due to the progress of the medical science and the growing burden of chronic disease. Accordingly, a real-time biomedical detection method that can be easily used to monitor chronic diseases by patients themselves is needed. Nowadays, the biochip technology becomes one of the mainstreams in IC design field, because it can integrate the biomedical measurement system into a small, light, and compact chip, which can analyze many kinds of measurands just by a small amount of samples.
Electrochemical impedance spectroscopic (EIS) is one of the most popular electrochemistry detection methods. The proposed impedance-to-digital converter (IDC) is used to integrate the EIS measurement system into a single chip, which can analyze the sample rapidly and automatically. Instead of using large-area circuits (e.g., low pass filter) in traditional EIS systems, the proposed circuit is simple and only requires a small chip area. Furthermore, it also achieves high-resolution digital conversion with the proposed innovative circuit architecture, and noise interference is greatly improved by the proposed circuit technique. Also, the proposed IDC can be used for a wide frequency range of input signals. Combing with the EIS measurement system and the automatic frequency-sweeping circuit, the proposed IDC can measure the magnitude and the phase information of measurand rapidly and automatically. Therefore, the proposed circuit can be used in many kinds of biomedical detection systems, such as real-time urine or blood detection.
This chip was fabricated by using Taiwan Semiconductor Manufacturing Company (TSMC) 0.35μm 2P4M 3.3V mixed-signal polycide process. The die area of this chip is . The measured power consumption is 0.831 mW at 3.3V. The input frequency range is 10 Hz - 10 kHz. Its maximal measurable magnitude and phase difference is 1.235V and +/- 177.4°, respectively.

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