- 學位論文
八位元精簡指令集微控制器於可攜式酸鹼度計訊號處理之設計與應用
An 8-bits RISC Microprocessor Design for ISFET-based Hand-held pH-meter Signal Process Applications
摘要
本研究主要是設計一顆八位元之微控制器，並將其應用於離子感應場效電晶體(Ion sensitive field effect transistor, ISFET) 感測器陣列訊號之讀取、校正與補償。由於ISFET感測器陣列中的每個感測器所輸出電之壓準位不同，且會因溫度的變化、量測的順序與反應時間的長短不同而使輸出的訊號產生漂移，所以在量測上不僅需要計算出相對的靈敏度，還需要做校正與補償，因此在本研究中是以自己所設計開發的微控制器來進行資料的運算與程序的控制，藉以進行感測器陣列的補償與校正，並計算出精準的pH值。 陣列型酸鹼溶液濃度量測系統與傳統單一感測器相比，確實是可提高量測值的可靠度、穏定度與準確度，且若能具有即時量測之功能，並提供操作方便之介面則更可提高其使用性與方便性。將所設計之微控制器應用於陣列型酸鹼溶液濃度量測系統，除減少電路設計之複雜度與降低晶片面積外並可達中央控制系統之目的，晶片微小化後則可提升其應用範圍，在本論文中除對所設計之微控制器做一深入的探討外，並說明如何以所設計之微控制器完成一酸鹼度計(pH meter)。
並列摘要
The objective of this research is to design an eight-bit microcontroller, which is used in a portable array-type pH-meter with ISFET sensors. With this controller, we can improve reliability, stability and accuracy of the pH-meter system. There are a lot of reasons will make the output signals produce by the sensor array drift in different experiments, such as the read-out voltages sensed by each sensor in ISFET sensor array have different reference levels, the variation in temperature, the orders we examined, and the different response time of each sensor. Therefore, we not only need to calculate the relative sensitivity in quantity, also need to adjust and compensate. In this reseach, we develop an eight-bit RISC architecture microcontroller and related software to do data calculation and process control. Compare to the traditional single sensor, array type pH-meter have a better reliability, stability and accuracy of the system. If the system has a user-friendly interface, it will promote its usability. According to the experiments we have done, we find out applying the microcontroller to the pH-meter system can abate the complexity of the circuit design and the chip area. In this thesis, we will do a deep discussion about how to design the microcontroller, and explain how to apply this microcontroller in a pH-meter system.