digital electronic is the branch in which most of the devices used work on direct current. this current is very less as compared to the current used in electrics. The direct current is more dangerous as compared to the altenating current, but it is harmful after a certain range like above 18 volts. But all the electronics appliances work below this range . The main things in digital electonics are 0 and 1.The whole of the digital electronics depends on 0 & 1. where o stands for 'off' and 1 for 'on'. It consists of logical gates and almost all the devices work on these gates .The basic gates are 'AND','OR','NOT' gates in this the AND gate performs multiplication, OR performs addition and the NOT gate acts as an inverter i.e if the input id 0 it converts it into 1 and vicersa. the gated derives from it are 'NAND' and 'NOR'. 'NAND' and 'NOR' are knows as universal gates, and with the help of these two gates all other gates can be derived it is called the realisation of gates. the other gates used in digital electronics. These two gates are derives from 'AND' gate and 'OR' gates. when a 'NOT' gate is added to 'AND' gate we get 'NAND' gate, and when a 'NOT' gate is added tp 'OR' gate we ger 'NOR' gate. The truth table of these gates are opposite to that of the gates from which it is derived. the other two gates are 'XOR' gate and 'XNOR' gate.
...MCA 102 DIGITAL SYSTEMS & LOGIC DESIGN
Module1 - Number systems and code. Number systems - Efficiency of number system, Decimal, Binary, Octal, Hexadecimalconversion from one to another- Binary addition, subtraction, multiplication and division, representation of signed numbers, addition and subtraction using 2’s complement and I’s complement. Binary codes - BCD code, Excess 3 code, Gray code, Alphanumeric code, Error detection codes, Error correcting code. Module II - Logic Gates and Boolean Algebra. Logic Gates - Basic logic gates- AND, OR, NOT, NAND, NOR, Exclusive OR, Exclusive NOR gates- Logic symbols, truth table and timing diagrams. Boolean Algebra - Basic laws and theorems , Boolean functions, truth table, minimization of boolean function using K map method, Realization using logic gates and universal gates. Module III - Combinational and Sequential Logic Circuits. Combinational circuits - Half adder, Full Adder, Parallel binary adder, Subtracter, Magnitude Comparator, Decoders, Encoders, Multiplexers, Demultiplexers, Parity bit generator, PLA. Sequential circuits - Flip Flops – RS, JK, T and D Flip Flops, Edge triggered Flip Flops, Master slave Flip Flops. Module IV - Registers and counters. Registers - Serial in serial out, Serial in Parallel out, Parallel in serial out, Parallel in Parallel out registers, Bidirectional shift registers, universal shift registers. Counters - Synchronous and asynchronous counters, UP/DOWN counters, Modulo-N Counters,...
...EEN1036 Digital Logic Design
Chapter 4 part I Simplification of Switching Function
1
Objective
s s s
s
Simplifying logic circuit Minimization using Karnaugh map Using Karnaugh map to obtain simplified SOP and POS expression Five-variable Karnaugh map
2
Simplifying Logic Circuits
• • •
A
A Boolean expression for a logic circuit may be reduced to a simpler form The simplified expression can then be used to implement a circuit equivalent to the original circuit Consider the following example:
B C
A B C + A BC
Y
AB C + AB C
Y = A B C + A BC + AB C + AB C
3
Continue ...
Checking for common factor: Y = A B C + A BC + AB C + AB C
= A C ( B + B ) + AB (C + C )
Reduce the complement pairs to ‘1’
Y = A C ( B + B ) + AB (C + C ) = A C + AB
Draw the circuit based on the simplified expression
A B C
Y
4
Continue ...
•
A
Consider another logic circuit:
B C
Y
Y = C( A + B + C ) + A + C
Convert to SOP expression:
Y = C( A + B + C ) + A + C = AC + B C + AC
Checking for common factor:
Y = A(C + C ) + B C = A + BC
5
Continue ...
• • Simplification of logic circuit algebraically is not always an easy task The following two steps might be useful: i. The original expression is convert into the SOP form by repeated application of DeMorgan’s theorems and multiplication of terms ii. The product terms are then checked for common factors, and factoring is performed wherever possible
6...
...Components
Structure and properties of Electronic Engineering materials, Conductors, Semiconductors and
Insulators, Magnetic, Ferroelectric, Piezoelectric, Ceramic, Optical and Superconducting materials.
Passive components and characteristics, Resistors, Capacitors and Inductors; Ferrites, Quartz crystal,
Ceramic resonators, Electromagnetic and Electromechanical components.
2. Physical Electronics, Electron Devices and ICs
Electrons and holes in semiconductors, Carrier Statistics, Mechanics of current flow in a semi-conductor,
Hall effect; Junction theory; Different types of diodes and their characteristics; Bipolar Junction
transistor; Field effect transistors; Power switching devices like SCRs, CTOs, power MOSFETs; Basics of
ICs-bipolar, MOS and CMOS types; Basics of Opto Electronics.
3. Network Theory
Network analysis techniques: Network theorem, transient and steady state sinusoidal response,
Transmission criteria: delay and rise time Elmore's and other definition, effect of cascading. Elements of
network synthesis.
4. Electromagnetic Theory
Transmission lines: basic theory, standing waves, matching applications, micro strip lines; Basics of
waveguides and resonators; Elements of antenna theory.
5. Electronic Measurements and instrumentation
Basic concepts, standards and error analysis; Measurements of basic electrical quantities and
parameters; Electronic measuring instruments and...
...Digitalelectronics, or digital (electronic) circuits, represent signals by discrete bands ofanalog levels, rather than by a continuous range. All levels within a band represent the same signal state. Relatively small changes to the analog signal levels due to manufacturing tolerance, signal attenuation or parasitic noise do not leave the discrete envelope, and as a result are ignored by signal state sensing circuitry.
In most cases the number of these states is two, and they are represented by two voltage bands: one near a reference value (typically termed as "ground" or zero volts) and a value near the supply voltage, corresponding to the "false" ("0") and "true" ("1") values of the Boolean domain respectively.
Digital techniques are useful because it is easier to get an electronic device to switch into one of a number of known states than to accurately reproduce a continuous range of values.
Digitalelectronic circuits are usually made from large assemblies of logic gates, simple electronic representations of Boolean logic functions.
Advantages
An advantage of digital circuits when compared to analog circuits is that signals represented digitally can be transmitted without degradation due to noise.[2] For example, a continuous audio signal transmitted as a sequence of 1s and 0s, can be reconstructed without error,...
...The instantaneous voltage of a waveform. Often used to mean maximum amplitude, or peak voltage, or a pulse.
Boolean Expression
An algebraic expression made up of Boolean variables and operators, such as AND (-), OR (+), or NOT (-). Also referred to as Boolean function or a logic function.
Clocked D Flip-Flop
Type of flip-flop in which the D (data) input is the synchronous input.
Digital Waveform
A series of logic 1s and 0s plotted as a function of time.
Dual In-Line Package (DIP)
One style of integrated circuit package which has two rows of lead.
Duty Cycle (DC)
Fraction of the total period that a digital waveform is in the HIGH state. DC = th/T (often expressed as a percentage: %DC = th/Tx100%).
Falling Edge
The part of a pulse where the logic level is in transition from a HIGH to a LOW.
Flip-Flop
A sequential circuit based on a latch whose output changes when its CLOCK input receives a pulse.
Frequency
The number of cycles per unit time of a periodic waveform.
Hertz (Hz)
Unit of frequency. One hertz equals one cycle per second.
Integrated Circuit (IC)
An electronic circuit having many components, such as transistors, diodes, resistors, and capacitors, in a single package.
Inverter
Also called a NOT gate or an inverting buffer. A logic gate that changes its input logic level to the opposite state.
Logic Diagram
A diagram, similar to a schematic, showing the connection of logic gates....
...Advantages of Digital Circuits
Name:
Instructor:
Institution:
Introduction
Digital circuits are circuits that use signals in digital form instead of analog forms. One distinctive feature of a digital signal is that it assumes discrete values, most of the time two values. A digital signal takes time to change from one value to another, and assumes intermediate values during transmission (Verma). Steady values are slightly inaccurate. Voltages within certain ranges are guaranteed to be interpreted as certain permitted values. In this technological era, digital circuits are more preferred in industries because of the many advantages they possess. Advantages range from good transmission due to low chances of being interrupted, to high efficiency.
Digital circuits also have disadvantages too but this assignment focuses more on advantages. Some of the notable disadvantages include use of more energy, hence more production of heat, they are more expensive due to high power consumption especially when in low qualities. This is just to mention a few.
Advantages of Digital Circuits
There are several advantages of digital circuits. These are the same features that make these circuits unique and efficient;
a) Signal Transmission Without Degradation
Degradation when a signal is...
...ANALOGUE & DIGITAL SIGNALS
Name: - BHAVESH PATWAL
Tutor : - JAY PATEL
Date: - 20th November, 2012
I . Analogue Signals : -
Analogue signal is a form of transmitting data such as voice, image or video using continuous signals. This is a relatively inexpensive way to transmit data. Analogue communications are usually sent via twisted cables or fibre optic cables and they are transmitted via a carrier signal which is set at a specific frequency.
The primary disadvantage of analogue signalling is that any system has noise – i.e., random unwanted variation. As the signal is copied and re-copied, or transmitted over long distances, these apparently random variations become dominant
Living examples: What we speak is analog signal.
II. Digital Signals : -
Digital Signals are much more common and desirable method of transmitting data. Digital information is put into a synchronized order to enable transmission. The information is then decoded when it reaches its final destination. There are not many opportunities for errors when using this method so information arrives intact and in the best quality possible.
One more aspect about digital signals they are binary digits that is they are represented using bits (Binary digits)
Until recently, most telephone, radio and television signals were sent via analogue communication devices and are still used in circumstances where...