篮球竞赛24秒计时器设计-(3)

目 录

第1章电路方案的选择及电路框图 .......................................................................................5

1.1 设计方案.......................................................................................................................5 1.2 电路框图.......................................................................................................................5 第2章 设计思路及其工作原理的介绍...................................................................................6

2.1 设计思路.......................................................................................................................6 2.2 基本原理.......................................................................................................................6 第3章 单元电路的设计...........................................................................................................8

3.1 24进制计数器的设计...................................................................................................8 3.2 数码显示电路的设计...................................................................................................9 3.3 秒脉冲的设计............................................................................................................. 11 3.4 控制开关电路的设计.................................................................................................13 3.5 报警电路的设计.........................................................................................................13 3.6 整机工作原理.............................................................................................................14 第4章 电路仿真.....................................................................................................................15

4.1计时预备阶段..............................................................................................................15 4.2计时阶段 ....................................................................................................................13 4.3暂停\连续功能的实现 ................................................................................................13 4.4电路报警......................................................................................................................13 第5章 安装及调试步骤.........................................................................................................15 第6章 故障分析与电路改进.................................................................................................20

6.1故障的分析和解决......................................................................................................20 6.2电路的改进. ...................................................................................................................20 结束语.......................................................................................................................................21 参考文献...................................................................................................................................22 附录1 篮球竞赛24秒计时器总电路原理图........................................................................23 附录2 元器件清单..................................................................................................................24