Alternatives
If a specific type of gate is not available, it can be constructed from other available gates. An XOR gate can be trivially constructed from an XNOR gate followed by a NOT gate. If we consider the expression, we can construct an XOR gate directly using AND, OR and NOT gates. However, this approach requires four gates of three different kinds.
An XOR gate can be made from four NAND or five NOR gates in the configurations shown below. In fact, both NAND and NOR gates are so-called "universal gates," and any logical function can be constructed from either NAND logic or NOR logic alone.
Read more about this topic: XOR Gate
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