近紅外光譜儀光電信號采集電路設計

測控論文編號:CK060   論文字數:13554,頁數:32

目 錄
摘要……………………………………………………………………………. . .……………..I
1  緒論………………………………………………………………………………………….1
 1.1  選題的背景與意義…………………...………………………………………………..1
   1.2  國內外研究現狀…………………………………………………………………….…1
   1.3  研究的主要內容和基本要求………………………………………………………….1
2  光電信號放大電路設計...…………………………………………………………….….3
2.1  總體電路設計…………………………………………………………………….……3
2.2  op07芯片介紹…………………………………………………………………............3
2.3  放大及濾波模塊設計……………………………………………………………….…4
3  A/D采集電路設計…………………………………………………………………..…...6
 3.1  系統總體結構框圖………………………………………………….……..………….6
 3.2  ADC0809和AT89C51芯片介紹…………………………………… ………………6
        3.2.1  ADC0809…………………………………………………… …………………6
     3.2.2  AT89C51……………………………………………………… ……………….9
 3.3  AT89C51與ADC0809接口電路……………………………………………………11
 3.4  A/D轉換的技術指標…………………………………………………………….….13
4  單片機與PC機串行接口電路設計…………………………………..……………..15
 4.1  系統總體結構框圖……………………………………..………….…………………15
 4.2  RS-232C標準與MAX232芯片簡介………………..………………………………15
 4.2.1  RS-232C標準………………………………………………………………….15
     4.2.2  MAX232芯片簡介……………………………………………………………16
 4.3  接口通訊………………………………………………………………..…………….16
        4.3.1  串口通信………………………………………………………………………16
        4.3.2  串行通信………………………………………………………………………19
    4.5  串行接口電路設計……………………………………………………………..…...20
5  總結………………………………………………………………………………………....23
致謝……………………………………………………………………………………………...24
參考文獻………………………………………………………………………………………25
附錄一  ADC0809與單片機通信程序…………………………………………………26
附錄二  單片機與PC機通信程序……………………………………………………...28

摘  要

 近紅外光譜（ NIR ）是近年來發展較為迅速的一種高新分析測試技術，是光譜測量技術、計算機技術、化學計量學技術與基礎測量技術的有機結合。本文通過對其中光電信號采集系統這一環節研究和設計，針對它的A/D轉換、數據采集及與上位機通信等內容進行分析。光電信號采集系統完成信號的放大處理和模數轉換，將采集到的模擬信號轉換成計算機可讀的數字信號，然后再將數據發送到單片機中進行處理，最后與上位機進行通信顯示結果等功能。其中放大電路采用芯片op07，轉換電路采用ADC0809，單片機采用AT89C51,通信電路采用MAX232及RS232。該電路方案合理可靠，設計簡單，性價比高，且提高了電路的穩定性與精度，具有一定的實用價值。

關鍵詞：信號采集、單片機、A/D轉換

Abstract

In recent years Near Infrared Spectrum (NIR) is one of the rapid development High-tech analysis and testing technology, which is organic integrated with spectrum measurement technology, computer technology, chemistry technology and the basis of measurement technology. This paper made the research and design based on photoelectric signal acquisition system ,for its A/D conversion, data acquisition and the communication with PC . Photoelectric signal acquisition system is completed with signal amplification, analog-digital conversion, which collected the analog signals and changed it so the computer can read it; then sent the data to the MCU for processing, finally communicating with the computer and show the results . Enlarge circuit which using op07, conversion circuit which using ADC0809, MCU which using AT89C51, communication circuit which using MAX232 and RS232. This circuit is a reasonable and reliable program, is designed simply, cost-effective and it improves the stability and accuracy of the circuit , so it has a certain practical value.
Keywords：Signal acquisition、mcu、A/D conversion