基于单片机的便携式谷氨酸浓度检测仪.doc

本科毕业设计(论文)

基于单片机的便携式谷氨酸浓度检测仪
摘要
本文研究设计了一种用于食品发酵领域的谷氨酸浓度检测仪。其设计方案基于89C52单片机,选择瑞士蒙巴波公司的CH20/S-10谷氨酸传感器。系统将传感器输出的4~20mA的标准信号通过以AD0832为核心的A/D转换电路调理后,经由单片机进行数据处理,最后由LCD显示谷氨酸浓度值。文中详细介绍了数据采集子系统、数据处理过程以及数据显示子系统和报警电路的设计方法和过程。系统对于样品超出规定的谷氨酸容许浓度时采用三极管驱动的单音频报警电路提醒监测人员。同时,操作人员对于具体报警点的上限值可以通过单片机编程进行设置。另外,该系统对浓度信号进行了信号补偿等处理,减少了测量误差,因此,具有较高的测量精度,而且结构简单,性能优良。
关键词: 谷氨酸,数据采集,A/D转换器,单片机
A DETECTOR BASED ON SINGLE-CHIP FOR THE DETECTION OF GLUTAMATE CONCENTRATION
ABSTRACT
This thesis designed a detector which is used in the field of food ferment to detect the concentration of glutamic. This design was based on 89C51 single chip, and CH20/S-10 glutamic sensor of Switzerland pany. The system could send the 2~4mA standard signal from the sensor into the A/D circuit which is based on the chip of ADC0832,then the data will be processed by the MCU, finally the glutamic density will be displayed by the LCD. This article introduced the design method and the process of the data acquisition subsystem, data processing and data displayed subsystem and alarm circuit in detail. When the glutamic concentration of the sample was beyond the specified value, the system will remind the monitored person by the single audio alarm circuit which was drivered by the transistor. At the same time,the upper limit of the concentration of glutamic can be set through the single-chip programming. In addition, the system will process the signal by pensation in order to reduce the measurement error, therefore, it had a high measurement accuracy and simple structure, excellent performance.
KEY WORDS:glutamic, data acquisition, A / D converter, single-chip
目录
中文摘要 I
英文摘要 II
1 绪论 1
引言 1
谷氨酸浓渡检测仪 2
2 系统概述 3
系统总概述 3
总体方案设计 3
硬件设计 3
软件设计 4
3 硬件设计 5
硬件设计主电路图 5
硬件选择 5
MCU的选择与简介 5
单片机最小系统的实现 5
数据采集系统 8
模数转换的选择与简介 9
按键选择与简介 11
外围扩充存储器 12
时钟芯片选择与简介 13
上拉电阻 14
液晶显示器简介 14
报警电路 16
电源充电管理模块 17
4