Question:
Write the truth table for a NAND gate connected as given in Fig. 14.45.
Hence identify the exact logic operation carried out by this circuit.
Solution:
A acts as the two inputs of the NAND gate and Y is the output, as shown in the following figure.
Hence, the output can be written as:
$Y=\overline{A \cdot A}=\bar{A}+\bar{A}=\bar{A}$ ...(1)
The truth table for equation (i) can be drawn as:
This circuit functions as a NOT gate. The symbol for this logic circuit is shown as: