基于LM331的纸张计数显示装置设计  

Design of Paper Counting Display Device Based on LM331

作　　者：王建卫 杨勋勇 张涵 Wang Jianwei;Yang Xunyong;Zhang Han(Guizhou University of Engineering Science,Bijie Guizhou,551700)

机构地区：[1]贵州工程应用技术学院,贵州毕节551700

出　　处：《电子测试》2022年第1期32-34,共3页Electronic Test

基　　金：大学生创新创业训练计划项目(202010668031)。

摘　　要：基于LM331设计了一种纸张计数显示装置,系统主要由单片机电路、振荡电路、频率电压转换电路、模/数转换电路以及显示电路构成。通过在平行极板间放入不同数量的纸张使得电容发生变化,振荡电路的输出频率将跟随电容的变化而发生变化,LM331电路将频率的变化转换成电压的变化,经模/数转换电路转换成数字信号后,再送入单片机进行处理并显示。经测试,纸张计数范围为0~89张,最大误差为1.1%。A paper counting display device was designed based on LM331.The system was mainly composed of MCU,oscillation circuit,frequency voltage conversion circuit,analog-to-digital conversion circuit and display circuit.The capacitance was changed when putting different amount of paper between the parallel electrode plates,and then the output frequency of the oscillating circuit was changed with the change of the capacitance as well.The LM331 circuit can convert the change of the frequency into the change of the voltage,then it would be converted into digital signal by the analog-to-digital conversion circuit,and sent to the MCU for processing and display.The test results showed that the maximum error was 1.1% when the paper amount of 0~89.

关 键 词：平行极板 振荡电路 频率电压转换电路 模数转换电路 

分 类 号：TH724[机械工程—仪器科学与技术]