A combinational circuit is one in which the output is solely dependent on the input(s).
A sequential circuit is one in which the output is dependent both on the input(s) and the current state.
Canonical form
has all of the variables in each minterm
(is another name for normal form).
We always want to simplify circuits (which makes them less expensive to build both in components and space). There are 2 methods of doing this (both in our text). One, which we are learning uses Karnaugh maps. The other is called Quine-McClusky. The Quine-McClusky method generalizes to circuits with many variables. Karnaugh maps don’t work well for more than 4 or 5 variables.
Sum of products for a number of variables as being in disjunctive normal form when each of the minterms ( product terms) contains each of the variables and the minterms are separated by sums (ors).
Product of sums form is in conjunctive normal form when each of the maxterms is a sum term, and the maxterms are separated by products (ands).
The x in the Karnaugh map of problem 6a is called a don’t care