气敏传感器信号采集系统设计_毕业论文.doc

气敏传感器信号采集系统设计 摘 要：随着电子领域的快速发展，采用电子设备探测气体引起了人们的广泛关注。由于年龄、经验、环境、身体状况等因素会存在一定的主观性，采用人或者其他动物对瓦斯、有毒气体、酒精、天然气等气体的检测，影响其判断力，而采用电子设备，利用传感器检测气体后经过A/D转换，再由MCU对其进行处理，能够得知气体浓度，对不良或者超标的检测结果进行报警灯功能，电子检测仪能高效的完成任务。由此被广泛应用于能源化工、环境污染检测、医疗、工业生产和交通等行业。 本文以AT89C51单片机为控制核心，设计了一套气敏传感器信号采集装置。气体采集的传感器采用MJC4/3.0L瓦斯检测传感器；A/D转换模块采用ADC0809将传感器检测到的电压进行数字化传送给MCU处理；运算放大器采用OP07模块；显示采用LED数码管，其驱动为MAX7219串行输入/输出共阴显示驱动；电源模块采用的是LM317稳压芯片。 关键词：气敏传感器；AT89C51；A/D转换；数码管显示  Design of Gas Sensor Signal Acquisition system Abstract:Along with the rapid development of the electronic field, adopting electronic equipment to detect gas has aroused extensive attention. Due to the subjectivity of age, experience, environment, healthy conditions, the detection of gases like gas, toxic gas, alcohol and natural gas practiced by people or animals will affect the accuracy of judgments, while electronic devices like sensors are adopted to detect gases. After the A/D conversion, gases are processed by MCU that can recognize the concentration of gases and show the alarm lamp for adverse or excessive results, so electronic detector can efficiently complete tasks. This method is widely employed in the energy and chemical industry as well as industries of environmental pollution detection, medical treatment, industrial production and transportation. Taking single chip Microcomputer of AT89C51 as the control core, this paper will design a set of signal collection devices with gas sensors. The sensor used for collecting gases is the gas detection sensor of MJC4/3.0 L; A/D conversion module utilizes ADC0809 to transmit digitized voltage detected by sensors to MCU. Operational amplifier is OP07 module and the display device uses LED digital tube whose display driver is serial input/output common cathode of MAX7219. Power module is LM317 voltage chip. Key words: Gas sensor; AT89C51; A/D conversion；Digital display 目 录 摘要 I Abstract II 目 录 III 1 引言 1 1．1 选题背景 1 1．2 国内外发展现状 1 1．3 本文设计方案 2 2 气敏传感器原理及MCU选择 3 2.1 气敏传感器 3 2.2 M