Vertical floating pins in OTC routing [VLSI layout]

Abstract

We present a generalized center terminal cell model and propose over-the-cell (OTC) routing algorithms, utilizing the new feature of the model, i.e., Vertical Floating Pins (VFPs). We approach the problem by linear integer programming and by dynamic programming. For further channel density reduction, both approaches have been combined with linear channel pin assignment. Experiments show a total density reduction by 45% compared to other OTC routing algorithms for center terminal cells.