文档介绍：摘要
智力竞赛抢答器是一种非常实用的电子电路,根据根据使用者要求的不同和难易程度,可以可以设计出多种电路。这里选择了一种难易程度适中、对初学者比较容易制作的电路。相对于分立元器件,用数字集成电路制作具有稳定性高、功耗小、调试简单、成本低、成功率高等优点。下面介绍用3个集成电路设计制作一个可以同时供8名选手抢答的智力竞赛抢答器演示板。只要掌握其制作原理和方法,对电路稍加改动,做成有实用价值的8路智力竞赛抢答器并没有太大的困难。
介绍了数码显示八路抢答器电路的组成、设计及功能,电路采用74系列常用集成电路进行设计。该抢答器除具有基本的抢答功能外,还具有定时、计时和报警功能。主持人通过时间预设开关预设供抢答的时间,系统将完成自动倒计时。若在规定的时间内有人抢答,则计时将自动停止;若在规定的时间内无人抢答,则系统中的蜂鸣器将发响,提示主持人本轮抢答无效,实现报警功能,若超过抢答时间则抢答无效。 
该抢答器主要运用到了编码器,译码器和锁存器:它采用74LS148来实现抢答器的选号,采用74LS279芯片实现对号码的锁存,采用74LS192实现十进制的减法计数,采用555芯片产生秒脉冲信号来共同实现倒计时功能,采用74LS121单稳态芯片来实现报警信号的输出。 
通过课程设计提高和巩固了所学的专业知识,以及知识的综合应用和焊接技术。
关键词:数字集成、演示板、抢答器、报警器、定时器、编码器、 译码 器
Abstract
Quiz responder is a very practical electronic circuit, according to the different degree of difficulty and according to user requirements, can design a variety of circuit. Here chose a moderate degree of difficulty, more easy to make circuit for beginners. Relative to the ponent, made of digital integrated circuit with high stability, low consumption, debugging is simple, low cost, high ess rate. Here are made of three integrated circuit design a can quiz for eight contestant vies to answer first vies to answer first device demo board. As long as to master the principle and method of circuit changed slightly, make it have practical value of 8 road quiz responder is not much difficult.
Introduces digital display eight-way responder position, function and design of integrated circuit to carry on the monly used circuit with 74 series. The buzzer in addition to the basic vies to answer first function outside, still have timing, timing and alarm function. The host through the preset time switch the default for the vies to answer first the time, system plete automatic countdown. If within the stipulated time someone vies to answer first, the timing will automatically stop; If within the prescribed time, no contest, the buzzer will send ring in the system and prompted to host the vies to answer first, realize the alarm function, if more than time vies to answer