课题：数字频率计摘要本文介绍了一种基于TTL系列芯片的简易数字频率计。数字频率计应用所学的数字电路知识进行设计。电路由放大整形电路、时基电路、逻辑控制电路、计数锁存电路及译码显示电路组成。能够较精准的测量幅值在0.2V~5V的正弦波、三角波、方波的频率。测量范围能够达到1Hz~9999Hz。关键词：频率计，TTL芯片，数字电路AbstractInthispaper,adesignofsimpledigitalcymometerbasedontheTTLseriseschipswasdescribed.Thisdesignisbasedontheknowledgeaboutthedigitalcircuitwelearned.Itconsistsofamplifierandshapingcircuit,time-basecircuit,controlcircuit,latchcircuitanddecodingcountshowcircuit.Itcanbeusedtoaccuratelydetectthefrequencyofsinewave,trianglewaveandsquarewaveaccuratelythattheamplitudeisbetween0.2Vand5V.Detectingrangecanbeachieved1Hz~9.99kHz..Keywords:cymometer,theTTLserieschips,digitalcircuit目录摘要..................................................................................................................................................I关键词..............................................................................................................................................IAbstract...........................................................................................................................................II引言.................................................................................................................................................11总体方案设计..........................................................................................................................22单元电路设计..........................................................................................................................32.1放大整形电路................................................................................................................32.1.1方案一.................................................................................................................32.1.2方案二.................................................................................................................42.1.3方案对比.............................................................................................................42.2时基电路........................................................................................................................52.2.1方案一.................................................................................................................52.2.2方案二.................................................................................................................52.2.3方案对比.............................................................................................................62.3逻辑控制电路................................................................................................................62.4计数器............................................................................................................................72.5锁存器............................................................................................................................83主要参数计算..........................................................................................................................93.1时基电路参数................................................................................................................93.2逻辑...
