數字電壓表的設計

電子機電論文編號:JD677  論文字數:16785,頁數:37

目  錄

前言……………………………………………………………………………………1
第1章  國內外新型數字電壓表概述…………………………………………………2
1.1數字電壓表的主要特點…………………………………………………………  2
1.2 數字電壓表的基本結構………………………………………………………… 3
1.3 直流數字電壓表準確度的測試方法…………………………………………… 4
第2章  ICL7107 型單片31/2位A/D轉換器…………………………………………5
2.1 ICL7107的主要特點……………………………………………………………  5
2.2 ICL7107的管腳功能……………………………………………………………  5
2.3 ICL7107的工作原理……………………………………………………………  7
    2.3.1 雙積分式A/D轉化器………………………………………………………7
    2.3.2 數字電路…………………………………………………………………15

第3章  由ICL7107構成的3 1/2位數字電壓表的設計……………………………24
3.1 31/2位數字電壓表的設計思想………………………………………………24
3.2 元器件的選擇…………………………………………………………………24
3.3 由ICL7107構成的31/2位數字電壓表電路設計…………………………26
3.4 使用注意事項…………………………………………………………………26
3.5 ICT7107的功能檢查與調試…………………………………………………29
第4章  數字電壓表印制電路板的設計……………………………………………31
結束語………………………………………………………………………………32
附錄 1 ICL7107構成3 1/2數字電壓表的元器件明細表…………………………33
     2 ICL7107構成3 1/2數字電壓表的照片……………………………………34
參考文獻……………………………………………………………………………35

摘 要
本課題是利用專用芯片ICL7107設計的3 1/2數字電壓表，它采用四位數碼顯示，能夠測量-20V～+20V之間的直流電壓值，而且使用的元器件數目較少。                                              ICL7107采用大電流反相輸出，靜態驅動共陽極LED顯示器，由±5V雙電源供電，顯示亮度高但耗電較大，適于制作小型臺式3 1/2位數字儀表。
工作過程如下：被測電壓在輸入電路部分經分壓器（電阻）進行分衰減后，送至A/D轉換器。通過A/D轉換變為數字信號，輸送給數字電路。然后由數字電路給LED數字信號，控制其發光，從而顯示數字。

關鍵詞：ICL7107；LED；時鐘振蕩器RC；雙積分式A/D轉換器

Abstract

This design is to makes use of the appropriate chip of ICL7107 to design a 3 1/2 arithmetic digital electric voltage form, it adopts four figureses show, can measure direct current voltage between -20V～+20V ,and the number of the chips are small. Big electric current in adoption in ICL7107 anti output mutually, the constant drives the anode LED display totally, be provided by power supply of ±5V, show that the bright degree is high but consume the electricity bigger, be suitable for the small scaled set in manufacture type 3 1/2 arithmetic figures appearance.
Work process is as follows:After the electric voltage which wanted to be measured was pressed by dividing  machine( resistance) proceeds to divide the reduces at the input of the electric circuit part ,it is sended to the A/ D conversion machine.Pass the A/ D conversion changes into the arithmetic figure signal, transporting to the arithmetic figure electric circuit.Then be given by arithmetic figure electric circuit LED arithmetic figure signal, control its give out light, from but manifestation arithmetic figure.

Key words:ICL7107;LED;The machine of clock oscillates RC;
An integral calculus type A/ D conversion machine