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Drive XOR from NAND or NOR gates  Only.
So the digital logic circuit to drive XOR from NAND is below.
First reformat the XOR equation.
Step 1 : A'B + AB' = [(A+B')' + (A'+B)'] using theorems T7, T8 & T9
Step 2 : [((A')'+B')' + (A' + (B')')'] using theorems T7, T8 and T9
Above are the steps to drive logic for XOR using NAND gates
XOR Truth Table:
A B Y
0 0 0
0 1 1
1 0 1
1 1 0
XOR equation = A’B + AB’
NOR Truth Table
A B Y
0 0 1
0 1 0
1 0 0
1 1 0
NOR equation = A’ B’
Digital logic gate conversion related interview questions. XOR from NOR., NAND to Inverter and XOR from NAND. Lets start our discussion with conversion for xor from nor gate only. The truth tables of XOR and NOR gates are below.
Check the circuit for NOR to inverter (equivalent of NAND to inverter). So the complete circuit for XOR using NOR gates. Diagram shown above.
Reformat XOR equation by following steps below:
XOR is also know as Exclusive OR.
Step 1 : A'B + AB' +AA’ + BB’ = [(A’+B') (A+B)] using postulate P4 and theorems T7, T8 and T9
Step 2 : [(AB)'(A’B’)’] using theorems T7, T8 and T9
In step 2, we do invert of A and invert of B.
Derive XOR by only using NOR gates. Steps
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XOR equation = A’B + AB’

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NAND equation = A’ + B’

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Lets start the discussion with truth tables of XOR and NAND.

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From Digital Basics section we know the equations for XOR and NAND gates. The equations are also shown above :

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Drive XOR gate from using only NAND gates.
