The synthesis of cyclic combinational circuits

Combinational circuits are generally thought of as acyclic structures. It is known that cyclic structures can be combinational, and techniques have been proposed to analyze cyclic circuits to determine whether this is the case [7]. Cycles sometimes occur in designs synthesized from high-level descriptions, as well as in bus-based designs [15]. However, feedback in such cases is carefully contrived, typically occurring when functional units are connected in a cyclic topology. No one has attempted the synthesis of circuits with feedback at the logic level. We propose a general methodology for the synthesis of multilevel combinational circuits with cyclic topologies. The technique, applicable in the substitution phase of logic synthesis, optimizes a multilevel description, introducing feedback and potentially reducing the size of the resulting network. We have incorporated the technique in a general logic synthesis environment and performed trials on benchmark circuits and randomly gener...

• Type: Conference
• Year: 2003
• Where: DAC
• Authors: Marc D. Riedel, Jehoshua Bruck
• Keywords: Combinational Logic, Cyclic Circuits, DAC 2003, Design Automation, Multilevel Combinational Circuits