- 1、本文档共89页,可阅读全部内容。
- 2、有哪些信誉好的足球投注网站(book118)网站文档一经付费(服务费),不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
- 3、本站所有内容均由合作方或网友上传,本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺!文档内容仅供研究参考,付费前请自行鉴别。如您付费,意味着您自己接受本站规则且自行承担风险,本站不退款、不进行额外附加服务;查看《如何避免下载的几个坑》。如果您已付费下载过本站文档,您可以点击 这里二次下载。
- 4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“版权申诉”(推荐),也可以打举报电话:400-050-0827(电话支持时间:9:00-18:30)。
查看更多
北科自动化数电pp6
CHAPTER 6 Functions of Combinational Logic In this chapter you should know: The internal functional principle of every MSI chips (in brief) Those MSI chips are combinational circuit (that means they are composed of logic gates); you should learn how to use them Focus on these two blocks named decoder and data selector which can be used to produce some given logic function 6-1 Basic Adders(implementing 1-bit addition) 基本加法器 6-1-1 Half-Adder(半加器) 6-1-2 Full-Adder 全加器 6-1-3 Full adder from two half-adder circuits 6-2 Parallel Binary Adders(implementing more-bit addition)并行二进制加法器 6-2-1 Two-bit parallel binary adder 6-2-2 Four-bit parallel binary adder 四位并行二进制加法器 ripple carry(串行进位) adder showing “worst-case” carry propagation delays. Another application of adder:A voting system 6-3 Comparators 数值比较器 Pin diagram and logic symbol for the 74HC85 4-bit magnitude comparator. 6-5 Encoders 编码器 Example: 用两片74LS148接成16线-4线优先编码器 Logic symbol for a decimal-to-BCD encoder. Pin diagram and logic symbol for the 74HC147 decimal-to-BCD priority encoder (HPRI means highest value input has priority). Application: A simplified keyboard encoder. Assignments: (due to next Monday) P232 6、8、12 补充作业题: 用4片74LS148组成32线-5线优先编码器,允许附加必要的门电路。 6-4 Decoders 译码器 6-4-1 Binary decoder(二进制译码器) 6-4-2 BCD-to-decimal decoder (BCD码-十进制译码器) 6-4-3 BCD-to-7-segement decoder (BCD码-七段显示驱动译码器) Binary inputs Active-low outputs 例:用两片74LS138接成4线-16线译码器 6-4-2 BCD-to-decimal decoder 6-8 Multiplexers (Data Selectors) 多路复用器/数据选择器(MUX) A MUX is a device that allows digital information from several sources to be routed onto a single line for transmission over that line to a common destination. The basic multiplexer has several data-input lines and a single output line. 4-input multiplexer Waveform 双4选1数据选择器74LS153 Pin diagram and logic symbol for the 74LS151 8-input data selector/multiplexer. Ex 6-17: Data selector/multiplexer connected as a 4-varia
文档评论(0)