An efficient approach to simultaneous transistor and interconnect sizing

In this paper, we study the simultaneous transistor and interconnect sizing (STIS) problem. We define a class of optimization problems as CH-posynomial programs and reveal a general dominance property for all CH-posynomial programs. We show that the STIS problems under a number of transistor delay models are CH-posynomial programs and propose an efficient and near-optimal STIS algorithm based on the dominance property. When used to solve the simultaneous driver/buffer and wire sizing problem for real designs, it reduces the maximum delay by up to 16.1%, and more significantly, reduces the power consumption by a factor of 1.63/spl times/, when compared with the original designs. When used to solve the transistor sizing problem, it achieves a smooth area-delay trade-off. Moreover, the algorithm optimizes a clock net of 367 drivers/buffers and 59304 /spl mu/m-long wire in 120 seconds, and a 32-bit adder with 1026 transistors in 66 seconds on a SPARC-5 workstation.