Postgrid Clock Routing for High Performance Microprocessor Designs

Designing a high-quality clock network is very important in very large-scale integrated designs today, as it is the clock network that synchronizes all the elements of a chip, and it is also a major source of power dissipation of a system. Early study by Pham in 2006 shows that about 18.1% of the total clock capacitance was due to this postgrid clock routing (i.e., lower mesh wires plus clock twig wires). In this paper, we proposed a partition-based path expansion algorithm to solve this postgrid clock routing problem effectively. Experimental results on industrial test cases show that our algorithm can improve over the latest work by Shelar on this problem significantly by reducing the wire capacitance by 24.6% and the wirelength by 23.6%.