To construct an 8-bit magnitude comparator, you need two C-MOS 4063, arranged in a cascade. The outputs X<Y, X=Y, X>Y of the first comparator IC1 constitute the inputs X<Y, X=Y, X>Y of the second comparator IC2...
In addition, the C-MOS 4063 has three more inputs (X<Y, X=Y and X>Y ). These are the so-called "cascading inputs". In the case of a 4-bit magnitude comparator these inputs are not used and therefore are connected as follows...
With the circuit shown you set up a 8-bit magnitude comparator consisting of two C-MOS 4063...
But not only two C-MOS 4063 can be set up in a cascade. The cascade can be extended in order to realize a 12-bit, 16-bit, etc. comparators...
Now you continue with some applications...