毕业设计 六路抢答器的设计.doc

摘 要 随着科学技术的不断发展，促使人们学科学、学技术、学知识的手段多种多样。抢答器作为一种工具，已广泛应用于各种智力和知识竞赛场合。但抢答器的使用频率较低，且有的要么制作复杂，要么可靠性低，减少兴致。做为一个单位若专购一台抢答器虽然在经济上可以承受，但每年使用的次数极少，往往因长期存放使（电子器件的）抢答器损坏，再购置的麻烦和及时性就会影响活动的开展,因此设计了本抢答器。 本文介绍了一种用74系列常用集成电路设计的高分辨率的4路抢答器。该抢答器为全数字集成电路设计，具有分组数多、分辨率高等优点。该抢答器除具有基本的抢答功能外，还具有优先能力、定时功能及复位功能。主持人通过控制开关使抢答器达到定时、复位的功能。电路主要由4D型锁存器、与非门构成的环形振荡器、逻辑控制电路、定时电路组成。与非门构成的可控环形振荡器由于没有外接任何元件，它依靠门电路自身的延迟时间而形成振荡，因此，其振荡频率很高，为提高抢答组之间的分辨时间提供了条件。 数字抢答器由主体电路与扩展电路组成。优先编码电路、锁存器、译码电路将参赛队的输入信号在显示器上输出；用控制电路和主持人开关启动报警电路，以上两部分组成主体电路。通过定时电路和译码电路将秒脉冲产生的信号在显示器上输出实现计时功能，构成扩展电路。 关键字：抢答电路； 定时电路； 报警电路； 时序控制； 抢答器; 集成电路;锁存器; 环形振荡器ABSTARCT With the continuous development of science and technology, promote learning science, science and technology, knowledge of the variety of means. With a tool for Qiangda, which has been widely used in all kinds of intelligence and knowledge contests occasions. But Qiangda is used for lower frequency, and some production complex or low reliability, and reduced interest. As a unit, if the purchase is a Qiangda .Although the economy can bear, each year the number is extremely small, because of the long-term storage (electronic devices) Qiangda for damage to the purchase of the trouble and timeliness of activities, The development will be affected, so this Qiangda is designed . A kind of highly distinguishable 4-circuit race answering device is designed with a series of commonly used intergarted circuit of 74.The device is all-digital design,which is benifical to devide more groups and resolute signals.In addition to the basic function of rece answering.It also has some other advantages such as the capital of pirority,the function of timing and reset .when using it,the moderator can control the switch to fulfil its function of timing and reset. The circuit is mainly composed by the 4D latch ,the non-gate contolled by ringlike oscillator,the logic controlled circuit and the timing circuit .The oscillator has no connection with any oher component and it just brings about vibartion th