Question

In the figure, the circuit symbol of logic gate and two input wave forms A and B are shown
(a) Identify the logic gate
(b) Write its truth table
(c) Draw the output waveform

Answer 1

	$A$	$B$	$y=A+B$
For $t_1$ to $t_2$	1	1	1
For $t_2$ to $t_3$	0	0	0
For $t_3$ to $t_4$	0	1	1
For $t_4$ to $t_5$	1	0	1
For $t_5$ to $t_6$	1	1	1
For $t_6$ to $t_7$	0	0	0
For $>$ $t_7$	0	1	1

a) OR gate

b)The Boolean expression for OR gate is y=A+B. It means, the output of an OR gate will be maximum if one or more inputs will be maximum.

Thus the output waveform will be as showing in Fig.by curve y.

The truth table of OR gates is shown above:

c) In the figure.