Conclusions

The model shown in this chapter is quite appealing for the calculus of the delay in CMOS structure, but it is inaccurate as far as we go into the submicron domain, so its use should be limited to a first validation of an optimization algorithm, but not for real production.
About this, it is important to note that the delay functions obtained by the Elmore's formula satisfy some properties useful in the optimization realm (for example equation (4.1), page ): then the Elmore model is very useful for optimization algorithms testing.