Design Of Digital Circuits - Dharmsinh Desai University

Design Of Digital Circuits Lab Manual
NOR GATE:
Fig:3.2 NOR GATE
o NOR is the contraction of OR – NOT gates.
o It has two or more inputs and only one output i.e. Y = A + B.
o When all the inputs are LOW, the output is HIGH. If any one or both the inputs are HIGH, then the
output is LOW.
o The Logic symbol and the truth table of NOR gate is as shown here.
o The small circle (or bubble) represents the operation of inversion.
o The NOR gate is equivalent to an AND gate with the bubble at its inputs which are as shown.
‣ A universal gate is a gate which can implement any Boolean function without need to use any other
gate type.
‣ The NAND and NOR gates are universal gates.
‣ In practice, this is advantageous since NAND and NOR gates are economical and easier to fabricate
and are the basic gates used in all IC digital logic families.
Department of Information Technology, Faculty of Technology, D. D. University, Nadiad.
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