Comparative analysis of new CMOS leaf cells for OTC routing

Recently four new cell models have been developed for over the cell routing. The usefulness of a cell model cannot simply be determined by utilization of OTC areas since cell widths, gate delays and layout parameters must also be considered. In this paper, we develop standard cells libraries in all the four models and compare the cell width and gate delay analysis of the cells. We also study the parameters which contribute to the variation in cell widths and gate delay between the different cell models. We show that the main parameters which contribute to the difference in cell widths in the four models are the number of terminals, intracell routing and cell functionality