A highly automated semi-custom approach for VLSI

The structured approach is aimed at optimizing the chip physical design while keeping design resources and time at a reasonable level. The logic is partitioned into data flow logic and control logic; a specialized physical structure has been defined to match the data flow logic structure and the gate array has been chosen for control logic implementation, both physical structures being customizable. A general purpose library and a set of design automation programs have been developed to allow fast physical design of the functional partitions according to the applications. A bipolar 16-bit slice microprocessor has been designed with this approach and built; compared to the widely used gate array chip implementation, it shows an improvement of 2 in gate density and 1.5 in power dissipation. The physical design of this 2000 gates chip took only two months.