## Thursday, 26 December 2013

### SWITCHING THEORY & LOGIC DESIGN

SWITCHING THEORY & LOGIC DESIGN
1.      A group of four bits is known as nibble.
2.      The number system with radix 2 is known as binary.
3.      The base or radix a Hexadecimal number system is 16.
4.      A half-adder can be constructed using 2 two input logic gates one of them is AND gate the other is OR gate.
5.      Hamming code is the most efficient method for detecting and correcting codes.
6.     3 to 8 decoder is the size of the decoder required to implement 3 Variable Boolean Function.
7.      Gray code is used in k-map to represent the data.
8.      Sequential PLD, Complex PLD, FPGA are the 3 types of sequential programmable devices.
9.      JQ~+K~Q is the characteristic equation for JK F-F.
10.                  Write about latches?
Ans: The most basic types of F-Fs operate with signal levels and are referred to as latches.
11. Define F-F s?
Ans: The storage elements used in clocked sequential circuits are called flip-flops.
12. What is the principle of duality?
Ans: Any theorem or Identity in switching algebra remains true if 0 and 1 are swapped and are swapped throughout.
13. What is the difference between mealy model and Moore model?
Ans: In the Malay model, the output is a function of both the present state and input. In the Moore model, the output is a function of the present state only.
14. 74 X 283 is a 4 bit binary adder.

15. 74 X 138 has 3 enable inputs