WHAT IS SO SPECIAL ABOUT DIGITAL SYSTEMS?
No area of technology has had or is likely to continue to have more of a profound impact on our lives than digital system development. That’s quite a statement, but its truth is obvious when one considers the many ways we have become dependent on “digitized” technology. To put this in perspective, let us review the various areas in which digital systems play an important role in our lives. As this is done, keep in mind that there is significant, if not necessary, overlap in the digital system technologies that make possible those areas we have come to take for granted: computing, information retrieval, communication, automatic control systems, entertainment, and instrumentation.
THE YEAR 2002 AND BEYOND?
If one considers what has happened in, say, the past 15 years, the path of future technological development in the field of digital systems would seem to be limited only by one’s imagination. It is difficult to know where to begin and where to end the task of forecasting digital system development, but here are a few examples in an attempt to accomplish this:
Computer power will continue to increase as the industry moves to 0.10/x (and below) CMOS technology with speeds into the terahertz range and with a demand for more efficient ways to sink the heat generated by billions of transistors per processor operated with supply voltages of one volt or below. There will be dramatic changes in the peripherals that are now viewed as part of the computer systems.
Expect that the mechanically operated magnetic storage systems (disk drives) of today will soon be replaced by a MR (magneto-resistive) technology that will increase the areal storage density (gigabits per square inch) by a factor of 100 to 200, or by OAWD (optically assisted Winchester drive) and MO (magneto-optical) technologies that are expected to increase the areal density even further. Eventually, a holographic storage technology or a proximal probe technology that uses a scanning tunnelling microscopic technique may provide capabilities that will take mass storage to near its theoretical limit. Thus, expect storage systems to be much smaller with enormously increased storage capacity.
Expect that long-distance video conferencing via computer will become as commonplace as the telephone is today. Education will be a major beneficiary of the burgeoning digital age with schools, universities and colleges both public and private being piped into major university libraries and data banks, and with access to the ever-growing WWW.
Expect digital systems to become much more sophisticated and pervasive in our lives. Interconnectivity between “smart” electrically powered systems of all types in the home, automobile, and workplace could be linked to the web together with sophisticated fail-safe and backup systems to prevent large-scale malfunction and possible chaos.
Optical recognition technology will improve dramatically in the fields of robotics, vehicular operation, and security systems. For example, expect that iris and retinal pattern recognition will eventually be used to limit access to certain protected systems and areas, and may even replace digital combination locks, IDs, and licenses for such purposes.
Business networking will undergo dramatic improvements with the continued development of gigabit Ethernet links and high-speed switching technology. Home connectivity will see vast improvements in satellite data service downloading (up to 400 kbps), 56-kbps (and higher) modems that need high-quality digital connections between phones and destination, improved satellite data service with bidirectional data transmission, and DSL (digital subscriber line) cable modem systems.
Finally, there are some really exciting areas to watch. Look for speech recognition, speech synthesis, and handwriting and pattern recognition to dramatically change the manner in which we communicate with and make use of the computer both in business and in the home. Somewhere in the future the computer will be equipped with speech understanding capability that allows the computer to build ideas from a series of spoken words. Thus, expect to see diminished use of the computer keyboard with time as these technologies evolve into common usage.
Revolutionary computer breakthroughs may come with the development of radically different technologies. Carbon nanotube technology, for example, has the potential to propel computer speeds well into the gigahertz range together with greatly reduced power dissipation. The creation of carbon nanotube transistors could signal the dawn of a new revolution in chip development. Then there is the specter of the quantum computer, whose advent may lead to computing capabilities that are trillions of times faster than those of conventional supercomputers. All of this is expected to be only the beginning of a new millennium of invention limited only by imagination. Remember that radically different technological breakthroughs can appear at any time, even without warning, and can have a dramatic affect on our lives, hopefully for the better.
A WORD OF WARNING
Not yet mentioned are the changes that must take place in the universities and colleges to deal with this rapidly evolving technology. It is fair to say that computer aided design (CAD) or automated design of digital systems is on the upswing. Those who work in the areas of digital system design are familiar with such hardware description languages as VHDL or Verilog, and the means to “download” design data to program PLAs or FPGAs (field programmable gate arrays). It is possible to generate a high-level hardware description of a digital system and introduce that hardware description into circuit layout tools such as Mentor Graphics. The end result would be a transistor-level representation of a CMOS digital system that could be simulated by one of several simulation tools such as HSPICE and subsequently be sent to the foundry for chip creation. The problem with this approach to digital system design is that it bypasses the need to fully understand the intricacies of design that ensure proper and reliable system operation. As is well known, a successful HSPICE simulation does not necessarily ensure a successful design. In the hands of a skilled and experienced designer this approach may lead to success without complications. On the other hand, if care is not taken at the early stages of the design process and if the designer has only a limited knowledge of design fundamentals, the project may fail at one point or another. Thus, as the use of automated (CAD) designs become more attractive to those who lack design detail fundamentals, the chance for design error at the system, device, gate, or transistor level increases. The word of warning: Automated design should never be undertaken without a sufficient knowledge of the field and a thorough understanding of the digital system under consideration — a little knowledge can be dangerous. The trend toward increasing CAD use is not bad, but automated design methods must be used cautiously with sufficient background knowledge to carry out predictably successful designs. Computer automated design should be used to remove the tedium from the design process and, in many cases, make tractable certain designs that would otherwise not be possible. But CAD is not a replacement for the details and background fundamentals required for successful digital system design.
|UNIT – I BINARY SYSTEM & BOOLEAN ALGEBRA|
|17.12.2014||3||Number Systems: Decimal, Binary, Octal, Hexadecimal number|
|18.12.2014||1||Number Base Conversions: Decimal to Binary, Octal and Hexadecimal, Binary to Decimal, Octal and Hexadecimal|
|20.12.2014||5||Octal to Decimal, Binary and Hexadecimal, Hexadecimal to Decimal, Octal and Binary|
|23.12.2014||2||Signed Binary Numbers: 1’s and 2’s Complement Arithmetic|
|24.12.2014||3||Binary codes – 8421, BCD, Excess 3 code, Gray code, BCD Addition and Subtraction|
|30.12.2014||2||Error detecting & Correcting Codes: Odd and Even Parity Generator and Checker, Hamming Code|
|31.12.2014||3||Boolean Algebra: Theorems & Properties: Commutative, Associative and Distributive Law, Consensus Theorem, De Morgan’s Theorem. Reduction of Boolean Expressions|
|03.01.2015||5||Boolean Functions – Canonical Form, Standard Form. Conversion from SOP to POS Form|
|06.01.2015||2||Simplification of Functions using K-map: Two, Three and Four variables|
|UNIT – II COMBINATIONAL LOGIC CIRCUITS|
|07.01.2015||3||Logic Gates – Types, Symbol, Truth Table|
|08.01.2015||1||Design of Binary Half Adder & Full Adder|
|13.01.2015||2||Design of Binary Half Subtractor & Full Subtractor|
|20.01.2015||2||Magnitude Comparator- Single Bit, 2 Bit|
|21.01.2015||3||Code converters – Binary to Gray, Gray to Binary|
|22.01.2015||1||Binary to BCD, BCD to Excess-3, BCD to Gray|
|27.01.2015||2||Encoders & Decoders: 2 X 4 , 3 X 8, 4 X 2, 8 X 3|
|28.01.2015||3||Multiplexers: 4:1, 8:1 16:1 MUX|
|29.01.2015||1||Demultiplexers: 1:4,1:8, 1:16 DEMUX|
|31.01.2015||5||Function Realisation using Logic Gates. AND/OR/INVERT to NAND/NOR Logic|
|UNIT – III SYNCHRONOUS SEQUENTIAL LOGIC CIRCUITS|
|10.02.2015||2||Introduction to Latches & Flip-Flops, Types of FFs. SR Flip flop: Excitation Table, Characteristic Equation|
|11.02.2015||3||JK and Master Slave JK Flip Flop: Excitation Table, Characteristic Equation|
|12.02.2015||1||D and T Flip Flops: Excitation Table, Characteristic Equation. Conversion of FFs|
|17.02.2015||2||Design of Shift Registers: SISO, SIPO, PISO, PIPO, Bidirectional Shift Register|
|18.02.2015||3||Design of Synchronous counters: Procedure, Mod – n Counters using JK and T FFs, Binary Up/ Down Counters|
|19.02.2015||1||Synchronous Sequential Machines: Mealy Model, Moore Model|
|21.02.2015||5||Analysis of Synchronous Sequential Circuits: Concepts of State, State Diagram, State table, Transition table|
|24.02.2015||2||Design of Synchronous Sequential Circuits: State Assignment, State Reduction, Output Table|
|25.02.2015||3||Design Procedure, Problems|
|UNIT – IV ASYNCHRONOUS SEQUENTIAL LOGIC CIRCUITS|
|26.02.2015||1||Introduction to Asynchronous Sequential Logic Circuits: Comparison between Synchronous and Asynchronous Sequential Circuits|
|03.03.2015||2||Types of Asynchronous Sequential Logic Circuits|
|04.03.2015||3||Concepts of State Table, Flow Table, Primitive Flow Table|
|05.03.2015||1||State Reduction Techniques – Merger Graph, Implication Table, Races, Cycles, Race Free State Assignment|
|07.03.2015||5||Analysis of Asynchronous Sequential Circuits: Procedure|
|10.03.2015||2||Design of Asynchronous Sequential Circuits: Problems|
|11.03.2015||3||Hazards: Types – Static, Dynamic and Essential Hazards, Elimination of Hazards|
|12.03.2015||1||Design of Hazard Free Digital Logic Circuits|
|UNIT – V MEMORY & PROGRAMMABLE LOGIC DEVICES|
|24.03.2015||2||Introduction & Classification of Memories: RAM – Static and Dynamic, ROM, PROM, EPROM, EEPROM, UVPROM|
|25.03.2015||3||Memory Decoding: Coincident decoding, Address Assignment|
|26.03.2015||1||Programmable Array Logic: Function Realisation using PAL|
|31.03.2015||2||Programmable Logic Array: Function Realisation using PLA|
|01.04.2015||3||Sequential Programmable Devices: Simple Programmable Logic Device, Complex Programmable Logic Device, Field Programmable Gate Array|
|07.04.2015||2||Digital Logic Families: Characteristics – Fan in, Fan Out, Delay Time, Propagation Delay|
|08.04.2015||3||Types – RTL, DTL, TTL, ECL, CMOS|
|09.04.2015||1||TTL – Totem Pole output, Current Sinking and Sourcing, TTL Logic Circuits|
|11.04.2015||5||ECL – Characteristics And Subfamilies, ECL Logic Circuits|
|15.06.2015||3||CMOS – Operating And Performance Characteristics, CMOS Logic Circuits|
|16.03.2015||1||Discussion: Binary System And Boolean Algebra|
|18.03.2015||5||Discussion: Combinational Logic Circuits|
|21.03.2015||2||Discussion: Synchronous Sequential logic Circuits|
|22.03.2015||3||Discussion: Asynchronous Sequential Logic Circuits|
|23.03.2015||1||Discussion: Memory And Programmable Logic Devices|
|Date Issued||Submission Date||Assignment Topics||Question Paper||Solution Manual|
|Binary System, Boolean Algebra and Combinational Logic Circuits||Download||Download|
|Project Design in “Sequential Logic Circuits”|
|Online Quiz in “Memory and Programmable Logic Devices”||Download||Download|