鎖相迴路應用於雙通道QCM感測晶片及Web監測平台設計

A PLL applied for a dual channel QCM sensing chip design and web monitoring platform

汪永晉(Yung-Chin Wang)

指導教授 ： 邱弘緯

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2010年)

摘要

石英晶體利用本身材料的反壓電效應，產生出一個規律的振盪，而此頻率與石英上的質量有關，而石英微質量天平利用此特性可被應用在生物感測。然而石英微質量天平在環境受到干擾的情況下，量測出來的結果無法精確的反應出待測物的濃度，因為石英受到溫度、濕度、非受體質量……等等的環境因素，而影響石英盪的頻率，本論文試圖提出一個有效的解決方案。
本論文提出使用雙通道QCM感測系統，在感測時使用兩組QCM感測晶片，分別為實驗組與對照組，而量測時兩個QCM感測器處於相同的環境下，理論上受到的環境干擾相同，而石英因為環境干擾所造成的頻率飄移也應該相同，因此採用雙端的系統便可以消除這些共模的效應，量得待測物的濃度。此外我們將鎖相迴路應用於感測電路上，鎖相迴路就好比一個頻率放大器，藉由鎖相迴路將石英晶體對於待測物質量變化而會造成輸出頻率的變化量提高，進而提QCM的解析度。此晶片在30~50℃溫度的變化量測下，單端量測的結果頻率會隨著溫度的上升而下降，但使用雙通道的架構，可以使得輸出頻率飄移量< 4Hz，達到消除共模干擾的影響。
隨著Web的發展，本論也設計一個基於網路的監測平台，提供RESTful的API，非常適合多種感測儀器數值資料的上傳，提供管理者一個便利的資料監控平台。

關鍵字

鎖相迴路 ； QCM ； 雙通道 ； SoC

並列摘要

The high mass sensitivity of piezoelectric quartz crystal microbalance (QCM) has widely used to detect nanograms particles. Especially, it is attempted to be the biological sensor for antibody, antigen, enzyme and protein by the affinity binding . The above biological materials always exist in the liquid which makes QCM measurement trouble.
In this paper we proposed a dual channel QCM sensing system to be a biological sensor in the liquid. This system uses dual channel QCM to detect the biological reactant by counting the frequency difference between two channels. The two frequencies are locked alternatively and amplified by a single PLL. The QCM sensing IC was fabricated and tested to have a small frequency variation < 4Hz from 30~50℃.
In few past years the web’s application is more and more popular. Therefore, in this theory also designed a web platform to monitor sensors measured data. This platform is base on the internet and provides RESTful API that is suit for variety of sensor devices.
And also provide a convenient monitoring platform for managers.

並列關鍵字

PLL ； QCM ； SoC ； Dual channel

參考文獻

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