Standard-cell-based design methodology for high-performance support chips

We describe the methodology used for the design of a set of CMOS support chips used in the IBM S/390(R) Parallel Enterprise Server Generations 3 and 4, The logic design is based on functional units, and the majority of the logic is implemented by standard cell elements placed and routed flat, using timing-driven techniques, Custom library elements are used wherever needed for performance reasons, Using this approach, a density has been achieved that is comparable to those of contemporary custom designs, combined with very attractive turnaround times.