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Getting through interviews is always a challenging task and requires thorough preparation . Here is a list of probable questions that may appear in an interview related to RTL skills.
Digital Interview Questions
Give two ways to convert a two input NAND gate to an inverter
Answer : -
Lets first look at the NAND truth Table below
First Method is connect the 1 bit input to either 'a' or 'b' and connect other to
always ‘1’. Detailed discussion below:-
So for the first method there can be two possible combinations.
First combination:-
For Row’s 3 and 4 Input A is always ‘1’
When Input B = 1 then the output is b= 0.
When Input B = 0 then the output is b=1.
Hence a functionality of an inverter.
Second combination:-
Row 2 and 4 in above table have Input A tied to 0. The polarity of B input is inverted at output.
Second Method : Apply same inputs to a and b
From table above we have in rows 1 and 4 following polarities.
Input a and b = 0 and output = 1
Input a and b = 1 and output = 0
So when both the inputs are tied together, we get an inverter.
NAND to Inverter conversion
