交通灯设计电路.doc

华 南 农 业 大 学 电子线路综合设计 交通灯控制电路设计 陈凌浩 王向聪 张雄 2011级 班级：电子类9班 组别：3组 指导老师：薛秀云 2013年6月20日 摘 要 本课题是关于交通灯控制电路的设计。本文从课程设计的题目出发，设计了一个南北方向、东西方向十字路口的交通灯控制电路。 首先进行了进行交通灯状态变换的分析和交通灯总体框架的设计，接着提出了两种电路设计方案，最后通过优劣比较选择了方案二：先先设计倒计时显示器按规律运行的电路，再通过倒计时电路的信号来控制交通灯的状态变换。 本交通灯控制电路采用74LS193芯片可预置四位二进制双时钟可逆计时器实现计数功能，并通过一系列集成逻辑门电路芯片控制红绿灯的交替显示。1Hz方波脉冲由555定时器产生；用两块74LS193芯片实现倒计时，一块显示十位，一块显示个位，相应的数字显示电路由两块CD4511芯片和7段显示器组成;用2个D触发器（74LS74芯片）实现30s,20s,5s时间的转换；利用倒计时电路控制交通灯的4个状态;最后通过相应的逻辑门控制红灯、黄灯、绿灯的亮灭。 关键词：交通灯 触发器 状态控制电路 The?Design?of?Digital?Control?Circuit?for?Traffic?Light Chen Linghao, Wang Xiangcong, Zhang Xiong （College of Engineer, South China Agricultural University, Guangzhou 510642, China）Abstract：This topic is about the design of traffic lights control circuit. Starting from the topic of curriculum design, designed a north-south direction and east-west intersection traffic lights control circuit.Basing on the analysis of the traffic light state transform and traffic light overall frame design ,this paper puts forward two kinds of circuit design, and finally choose the solution 2 by comparing advantages and disadvantages. Firstly ,design the countdown display according to the law of operation circuit, and then use the countdown circuit signals to control the traffic light state transformation. The traffic lights control circuit adopts 74LS193 clip which can be preset four binary reversible double clock timer to realize counting function, and use a series of integrated logic gate clips to control traffic lights for alternate display. 1 Hz square-wave pulse can be generated by the 555 Timer. Using two pieces of 74LS193 clips to countdown, one displays tens digit , the other displays units digit , and the corresponding digital display circuit is composed of two CD4511 chips and 7 segment display. Using two D triggers(74LS74 clip) to realize time transformation of 30s, 20s and 5s,also using the countdown circuit to control the four states of traffic light. Finally, using the corr