question_answer

The following figure shows the input waveforms (A, B) and the output waveform \[(\Upsilon )\] of a gate. Identify the gate, write its truth table and draw its logic symbol.                 

Answer:

                    Clearly, the output is low when both the inputs are high otherwise it is high. Hence it is a NAND gate.                     When the output of NAND gate is fed to a NOT gate.

Input A	Input B	Output of NAND gate\[\Upsilon '=\overline{\text{A}\text{.B}}\]	Output of NOT gate \[\Upsilon =\overline{\Upsilon }'\]
0	0	1	0
0	1	1	0
1	0	1	0

  Clearly, output \[\Upsilon =A\,.\,B.\] So the new logic gate formed is an AND gate.