数字逻辑1-1课件

Digital Design Pinciples and Practices Chapter 1:Introduction uWhy study digital design?uDigital signal u Digital system u The arrangement of the course Why Study Digital Design?Look“under the hood”of computersSolid understanding-better programmer when aware of hardware resource issuesElectronic devices becoming digitalEnabled by smaller and more capable chipsEnables:Better devices:cameras,cars,medical devices,TVs.New devices:smart phones,robots,.Known as“embedded systems”Thousands of new devices every yearDesigners needed:Potential career direction1995Portablemusic players1997Satellites1999Cell phones2001DVDplayersVideorecordersMusicalinstruments2003CamerasTVs?20052007Years shown above indicate when digital version began to dominate(Not the first year that a digital version appeared)Signals in electric circuituReal signal:voice,music,moving pictureuAnalog signal:voltage changed with time.uDigital signal:sampling values from analog From Analog to DigitalSamplingholdchange to digital0.85:1101 10010.85:1101 10010.81:1100 11110.81:1100 11110.65:1010 01100.65:1010 01100.49:0111 11010.49:0111 11010.39:0110 00110.39:0110 0011 Digit in decimal systemDigit in binary systemThe problem for Analog signaluEasy to be disturbuShift with temperature uHard to be recordeduCan not express abstract informationThe advantage of digital signaluOn each data line,the signal is very simpleuNot influenced by circumstance and deviceuCan be recorded and transmitted easilyuAny information can be coded Digital signal Digital signal:the string of 1 and 0 1 :High voltage or the power source;0 :Low voltage or the ground;Use several lines to transmit one digit;Only changed in discrete time!One binary digit is a bit.One byte has 8 bits.Digital system Any inputs and outputs can only be 1 or 0!For each output,its state must be get from all the inputs.Basic logic in digital system NOT gate (inverter,INV)Buffer Basic logic in digital system AND gate diagram equation Truth table Three forms of a logic Basic logic in digital system OR gate Other Basic logicNANDNOROther Basic devicesXORBuffer:y=aInverter:y=abasic logic system with one or more inputsbasic logic system with one or more inputsTwo classes of digital circuit Without memory and states Combinational logic Sequential logicWith memory and states The integrated circuit:IC SSI:1 to 20 gates;simple devices 60s(Small Scale Integrated)MSI:20 to 200 gates;functional devices 70s(Medium Scale Integrated)LSI:200 to 200 000 gates;complex devices or simple systems 80s(Large Scale Integrated)VLSI:?systems on chip (SOC)90s(Very Large Scale Integrated)Moores law:Doubling in every 18 months Moores lawMoores LawIC capacity doubling about every 18 months for several decadesKnown as“Moores Law”after Gordon Moore,co-founder of IntelPredicted in 1965 predicted that components per IC would double roughly every year or soThe figure on the right depicts related phenomenaFor a particular number of transistors,the IC area shrinks by half every 18 monthsConsider how much shrinking occurs in just 10 years(try drawing it)Enables incredibly powerful computation in incredibly tiny devicesTodays ICs hold billions of transistorsThe first Pentium processor(early 1990s)needed only 3 millionAn Intel Pentium processor IChaving millions of transistorsThe target of digital design Gates design Design basic device by transistors Functional design Design functional circuits by basic device combinational logic sequential logicThe arrangement of the course Teach in 32 times:Arithmetic and device Chap.1,2,3 7 Combinational circuit Chap.4,5,6 10 Sequential circuit Chap.7,8,9 14Memory and ADC/DAC 1结束语当你尽了自己的最大努力时，失败也是伟大的，所以不要放弃，坚持就是正确的。When You Do Your Best,Failure Is Great,So DonT Give Up,Stick To The End感谢聆听不足之处请大家批评指导Please Criticize And Guide The Shortcomings演讲人：XXXXXX 时 间：XX年XX月XX日