應用於心電圖量測之連續漸進式類比數位轉換器

A Successive Approximation Analog-to-Digital Converter for Electrocardiography Applications

呂雨柔(Yu-Jou Lu)

指導教授 ： 施鴻源

淡江大學/工學院/電機工程學系碩士班/碩士(2020年)

https://doi.org/10.6846/TKU.2020.00087

摘要

隨著醫療技術不斷進步，導致老年人口增加，各種文明疾病也層出不窮。此外，近年來電子技術蓬勃發展。因此將電子技術與醫療結合成為一種趨勢。台灣擁有先進的半導體製程技術，能夠製作低功耗且面積小的晶片，達到生醫電子超低功耗的需求。將穿戴裝置用以偵測各種生理訊號達到居家照護的目的將成為趨勢。
心電圖是紀錄心臟跳動時電壓變化的一種圖形。因心臟的肌肉有自動規律收縮的特性，所以在收縮之前會先在心臟的傳導系統產生一個激動波，激動波會使整個心臟的肌肉興奮而產生收縮。這些激動波的產生和傳導會形成微弱的電流而分佈到全身。若將心電圖記錄器的電極連接到身上不同的部位，就可以記錄而得到心電圖。根據心電圖的量測結果來判斷是否有心律不整的疾病，將心電圖的貼片貼在胸前，再將心電圖記錄器安置在病人身上，作長時間的監控及記錄心臟是否規律的跳動來即時發現心臟疾病的發生。
我們要量測的心電訊號屬於低頻訊號，訊號頻率約為0.15Hz ~150Hz且振幅微小僅10mV的範圍。此設計中採用UMC 0.18um CMOS標準製程來實現一個應用於心電圖量測的類比數位轉換器，其工作電壓為1.8V，取樣頻率為4KHz，Pre-Simulation的ENOB達到9.7，平均功耗為18.18μW。

關鍵字

類比數位轉換器 ； 心電圖量測 ； 低功耗

並列摘要

With the continuous advancement of medical technology, the elderly population has increased, and various civilization diseases have emerged in an endless stream. In addition, electronic technology has flourished in recent years. Therefore, the combination of electronic technology and medical treatment has become a trend. Taiwan has advanced semiconductor manufacturing technology that can produce chips with low power consumption and small area to meet the ultra-low power consumption requirements of biomedical electronics. It will become a trend to use wearable devices to detect various physiological signals for home care purposes.
An electrocardiogram is a graph that records changes in voltage when the heart beats. Because the heart muscles contract automatically and regularly, an excitement wave is generated in the conduction system of the heart before contraction. The excitement wave excites the entire heart muscle and produces contraction. The generation and conduction of these excitatory waves will form a weak current and be distributed throughout the body. If you connect the electrodes of the ECG recorder to different parts of your body, you can record and get an ECG. Determine whether there is arrhythmia disease according to the measurement results of the electrocardiogram, stick the electrocardiogram patch on the chest, and then place the electrocardiogram recorder on the patient, monitor for a long time and record whether the heart is beating regularly for immediate detection The occurrence of heart disease.
The ECG signal is a low-frequency signal, the signal frequency is about 0.15 Hz ~ 150 Hz and the amplitude is only 10mV. In this design, UMC 0.18 um CMOS standard process is used to realize an analog-to-digital converter for ECG measurement. Its working voltage is 1.8 V, sampling frequency is 4 KHz, Pre-Simulation ENOB reaches 9.7, and average power consumption is 18.18 μW .

並列關鍵字

Analog-to-digital converter ； ECG measurement ； low power consumption

參考文獻

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