Editing CMOS (section)

=== Duality ===
An important characteristic of a CMOS circuit is the duality that exists between its PMOS transistors and NMOS transistors. A CMOS circuit is created to allow a path always to exist from the output to either the power source or ground. To accomplish this, the set of all paths to the voltage source must be the [[Complement (set theory)#Logical complement|complement]] of the set of all paths to ground. This can be easily accomplished by defining one in terms of the NOT of the other. Due to the logic based on [[De Morgan's laws]], the PMOS transistors in parallel have corresponding NMOS transistors in series while the PMOS transistors in series have corresponding NMOS transistors in parallel.