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digital design basics

 VLSI Technologies are now maturing with a current emphasis on submicron structures and sophisticated applications combining digital and analog circuits on a single chip.

here, we have 

1. digital :

digital means mainly,

switching circuits: because the voltage levels in a digital circuit are assumed to be switched from one value to another.

logic circuits: Each type of digital circuit obey a certain set of logic rules.

Digital circuits are one in which the voltage levels assume a finite number of the distance value.


2. Analog:

it was a continuously variable signal, analog circuits are those in which voltages and currents vary continuously through the given range. That can make infinite values within the specified range.

Started from :

1. Number system 

2. Grey coding

3. Complement's

4. Error detecting and decoding

5. Hamming code

6. Logic gates

7. Boolean algebra

8. K-maps 

9. Inverter

Number System:

It's a combination of different collections of numbers and it satisfies the same kind of requirements.

example: Decimal number systems

               Binary number systems



 1. Binary number system :

In a binary number (or base two) system, we use only two digits: 0 and 1






 2. decimal number system :

  A digital system can understand a positional number system only where there are a few symbols called digits and these symbols represent different values depending on the position they occupy in the number.


3. octal number system :

It is called the base 8 number system and It uses eight digits, 0,1,2,3,4,5,6,7.
.
example :

125708   = ((1 × 84) + (2 × 83) + (5 × 82) + (7 × 81) + (0 × 80))10

               = 549610

4. hexadecimal number system :

It is called the base 16 number system.It uses 10 digits and 6 letters, 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F.

19FDE16   = ((1 × 164) + (9 × 163) + (F × 162) + (D × 161) + (E × 160))10
                  = (65536 + 36864 + 3840 + 208 + 14)10    =10646210











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