Before seeing the chapter please follow the previous chapter:
Design circuit with Minimum NAND gate, Important points
Like NAND gate (two-level AND OR hierarchy) same way, if we try to implement any circuit by NOR then try to write it POS order because POS is two level of OR – AND hierarchy.
Example:
How many minimum 2 inputs NOR gate will be required to implement (A + B) (C + D).
Solution:
This circuit is POS (Product of Sum) means two-level of OR – AND hierarchy.
Now because it is a two-level of OR – AND hierarchy we can easily convert it by NOR.
First, we can put the ‘not’ bubble in two-level of OR and then cancel it by putting a double bubble at AND gate.
Now we know:
Here double bubble AND is equal to NOR.
Then we can write,
So, minimum three (3) NOR gate is required to implement (A + B) (C + D).
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