Question
Write the truth table for the circuits given in figure. Consisting of NOR gates only. Identify the logic operations (OR, AND, NOT) performed by the two circuits.
Solution
Figure (a) represents NOT gate.
Here, when A = 1, Y = 0
and
when A = 0, Y = 1
Figure (b) represents two NOT gates whose outputs are given to NOR gate.
Truth table for this circuit is:
|
A |
B |
Ā |
Y |
|
|
0 |
0 |
1 |
1 |
0 |
|
0 |
1 |
1 |
0 |
0 |
|
1 |
0 |
0 |
1 |
0 |
|
1 |
1 |
0 |
0 |
1 |
which is the truth table of AND gate.
The logic operation performed by circuit in figure (b) is AND operation.
