CARLOS: an automated multilevel logic design system for CMOS semi-custom integrated circuits

CARLOS, a program system for the automated synthesis of random combinational CMOS logic, is described. The input of CARLOS is a specification of a multiple-output Boolean function in the form of a truth table. CARLOS produces an optimized random logic circuit composed of NAND, NOR, and complex gates under the given fan-in and fan-out limitations. The algorithms implemented in CARLOS are based on logic minimization, novel multiple-output multilevel factoring strategies, and recursive technology mapping. The factorization algorithm performs multiple-output synthesis using an algebraic representation of multiple-output Boolean functions. Tests on a large set of examples have shown the efficiency of the synthesis in terms of circuit size as well as computation time. CARLOS is an integral part of a larger CAD system that supports the automatic logic and physical design of finite-state machines under gate-array constraints.<
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