3、with theprogressoftimes, moreandmorepeople use electronicequipment, whetherthefamilyor thefactoryuse electricalappliancesare moreandmore. It is becauseof theimproperuseof electricalappliances causedby fire isalsoverymuch. Ourcountry eachyearbecauseof theuseofelectric firecausedbythe
4、 lossof alotofinterests. Firenotonly broughtthe goods propertylosses, butalso broughtus thegriefoflosinglovedones. So inthiscase itisnecessaryforus todesigna firealarmsystem, reducethefire, and weare inthefirecasualtiesandeconomiclosses to theminimum. Atpresent, ourcountryhas somany
5、peoplehave designedalotof firealarmsystem, butmostofthe firealarmsystem is applicabletolarge factories, companies and isnot suitableforfamilies, dormitoriesandother smallenvironment. Sothedevelopmentof a needle isveryimportantfor families, dormitoriesandother smallenvironment develo
6、peda firealarmsystem. And thisdesign is conciseandcomprehensive, highlypractical. Soforthe small environment ofthefirealarmsystem thispaperdesigneda firealarm. Thecoreofthesystemdesign fortheMCS-51MCU andMQ-2chip semiconductorgas smokesensor, weadoptSTC89C52chip, thefirealarm circui
7、t inthesystemincludingthe smoke signalacquisition circuit, preamplifiercircuit,A/Dconversioncircuit,protectioncircuit main circuit. After debugging, the design schemeisfeasible.Keywords:sensor;MCU;Thesmokealarm目录1绪论11.1课题背景11.2烟雾报警器的国内外现状12总体方案设计22.1烟雾检测传感器选型32.2单片机选型42.2.1STC89C52单