應用於電子舌系統之多參數感測電路設計

Multi Parameters Sensing Circuit Design for Electronic Tongue System

何維柏(Wei-Po Ho)

指導教授 ： 鍾文耀

中原大學/工學院/電子工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000684

摘要

由於近年來對環境保護議題、優質生活等議題漸趨重視，其與民生及環境保護相關之水質監控更成為近年來熱門研究之課題，未來將朝向整合多種離子檢測並結合無線傳輸來構成一長期環境監控之系統。

本研究係備製以離子敏感場效電晶體為基板之鈉離子感測器，並使用商用複合式電極搭配離子敏感場校電晶體實現一具多參數感測電路，其具有氫離子、鈉離子、溫度等參數讀出，並針對前端讀出電路進行積體化電路的開發與設計。文中所設計之電路區塊包含一虛短路離子選擇電極讀出電路、能隙帶參考電壓電路、低壓降線性穩壓器，並透過TSMC 0.35um 2P4M Mixed-Signal 3.3/5V製程技術實現。

實驗結果顯示本研究所開發之鈉離子感測元件，於pNa = 1~4中，可獲得電壓感測度為-58.3mV/pNa、線性度99.5%與偵測極限為pNa = 3.6(5.7ppm)，感測元件範圍廣、線性度佳且再現性佳，適合應用於水質監測系統，讀出電路下線部份，已實現氫離子、鈉離子、溫度等多參數之訊號讀出。

關鍵字

鈉離子感測器 ； 多參數讀出電路 ； 水質監測

並列摘要

In recent years, the environment and quality of life has become an important issue. Environmental and livelihood related water quality monitoring has become a topic of interest for research. The target is to be able to integrate a sensor that detects a variety of ion with wireless transmission to form a long term monitoring system.

This study prepared a sodium sensor based on ion-sensitive field-effect transistor combined with a commercial differential electrode to achieve multi parameters sensing circuit. The system is an integrated circuit design of a readout circuit for hydrogen ion, sodium ion, and temperature parameters. This research includes design of an ion-selective electrode readout circuit, bandgap reference voltage circuit, a low dropout linear regulator. The system was designed using the TSMC 0.35um 2P4M Mixed-Signal 3.3/5V process technology.

Experimental results shows that the sodium ion sensor, at pNa = 1 ~ 4, has a sensitivity of -58.3mV/pNa. The linearity is at 99.5% and the detection is limited at pNa = 3.6 (5.7ppm). It has a wide sensing range, good linearity and good reproducibility that is suitable for water quality monitoring system. The readout circuit part has achieved readout for the hydrogen ions, sodium ions, temperature and many other parameters.

並列關鍵字

multi parameters readout circuit ； water quality monitor ； Sodium sensor

參考文獻

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