LECTURE-3
NAND AND NOR IMPLEMENTATION
Any logic function can be implemented using NAND and NOR gates.
To achieve this, first the logic function has to be written in Sum of Product (SOP) form. Once
logic function is converted to SOP, then is very easy to implement using NAND gate. In
other words any logic circuit with AND gates in first level and OR gates in second level can
be converted into a NAND-NAND gate circuit.
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Consider the SOP expression: F = W.X.Y + X.Y.Z + Y.Z.W
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The above expression can be implemented with three AND gates in first stage and one OR
gate in second stage as shown in figure.
If bubbles are introduced at AND gates output and OR gates inputs (the same for NOR
gates), the above circuit becomes as shown in figure.
