21. Controlled Buffer/Inverter Synthesis

A reconfigurable buffer/inverter is synthesized using only XNOR gates by exploiting their behavior as equivalence detectors. The first XNOR gate has one input tied to a logic low (0) to act as an inverter for the Config signal. The second XNOR gate combines this inverted control signal with Data In to dynamically toggle between a non-inverting buffer and an inverter.

Boolean Equation:

Data Out = Data In ~^ (Config ~^ 0)