1、 毕业论文(设计) 数字时钟的设计及原理数字时钟的设计及原理 2012 年 3 月 5 日 摘 要 本文针对简易数字钟进行了设计及原理的分析,提出了整体的设计方案,进行 了由上而下层次化的设计.首先对各部分单元电路进行了详细的设计,对各部分的 电路原理及所需要的元器件进行了分析,以及做出了各部分的电路图,其中包括振 荡电路、计数电路、校时电路、译码与显示电路等.振荡电路由振荡器和分频器 两部分构成,计数电路是用两个六十进制计数电路和一个“12 翻 1”计数电路实 现的,校时电路用到的元器件有三块四-2 输入与非门 74LS00 、一块六反相器 74 LS04 等,译码与显示电路由译码器、显示器
2、构成.最终达到了设计的目的,完成了 数字时钟显示时、分、秒的功能,而且能够通过校时电路对时、分准确校时.并在 此基础上进行了扩展,完成了整点报时电路的设计,最终完成了设计任务. 关键词:数字时钟;校时电路;译码;报时器 ABSTRACT The design and analysis of the principle of simple digital clock, the overall design scheme, a top-down hierarchical design.Detailed design of the first part of the unit circuit, on
3、 the part of the circuit and the required components were analyzed, and made various parts of the circuit, including the oscillation circuit, counting circuit, timing circuit translationcode and display circuit. The oscillator circuit from the oscillator and divider of two parts, the counting circui
4、t is implemented with two six decimal counting circuit and a 12 turn a counting circuit, the circuit components used in the school three 40 -2 input NAND gate 74LS00, a hex inverter 74 LS04, etc., decoding and display circuit by the decoder, the display constitutes. Ultimately achieve the purpose of the design to complete the digital clock display hours, minutes, seconds, and through the school circuit, sub-accurate school. On this basis, an extension to complete the whole point timekeeping circ